Title of Invention	METHODS FOR PRODUCING SULFONIC ACID DIAMIDES
Abstract	The present invention relates to a method for producing sulfonic acid amines of the general formula (I) R1R2N- S(O)2-NH2 (I), where R and R are independent of each other and stand for a primary alkyl radical having 1 to 8 C atoms, a secondary alkyl radical having 3 to 8 C atoms, or a cycloalkyl radical having 5 to 8 C atoms, or, together with the nitrogen atom, form a 5- to 8-member saturated nitrogen heterocyclic compound that can comprise, in addition to the nitrogen atom, an additional hetero atom, selected from O and S, as a ring member, wherein the nitrogen heterocyclic compound is unsubstituted, or can comprise 1, 2, 3, or 4 alkyl groups each having 1 to 4 C atoms as substituents. The method comprises the following steps: i) conversion of a secondary amine of the formula (II) R1R2NH (II), where R and R have the meaning indicated above, having sulfuryl chloride in an inert, particularly aromatic, solvent in the presence of a tertiary amine, to form a sulfamoyl chloride of the formula (III) R1R2N-S(O)2-CI (III), where R1 and R2 have the meaning indicated above, and ii) conversion of the sulfamoyl chloride of the formula (III) obtained in step i) using ammonia, wherein in step ii) the sulfamoyl chloride of the formula (III) is used in the form of the solution obtained in step i) in the inert, particularly aromatic, solvent.

Title of Invention

METHODS FOR PRODUCING SULFONIC ACID DIAMIDES

Abstract

The present invention relates to a method for producing sulfonic acid amines of the general formula (I) R1R2N- S(O)2-NH2 (I), where R and R are independent of each other and stand for a primary alkyl radical having 1 to 8 C atoms, a secondary alkyl radical having 3 to 8 C atoms, or a cycloalkyl radical having 5 to 8 C atoms, or, together with the nitrogen atom, form a 5- to 8-member saturated nitrogen heterocyclic compound that can comprise, in addition to the nitrogen atom, an additional hetero atom, selected from O and S, as a ring member, wherein the nitrogen heterocyclic compound is unsubstituted, or can comprise 1, 2, 3, or 4 alkyl groups each having 1 to 4 C atoms as substituents. The method comprises the following steps: i) conversion of a secondary amine of the formula (II) R1R2NH (II), where R and R have the meaning indicated above, having sulfuryl chloride in an inert, particularly aromatic, solvent in the presence of a tertiary amine, to form a sulfamoyl chloride of the formula (III) R1R2N-S(O)2-CI (III), where R1 and R2 have the meaning indicated above, and ii) conversion of the sulfamoyl chloride of the formula (III) obtained in step i) using ammonia, wherein in step ii) the sulfamoyl chloride of the formula (III) is used in the form of the solution obtained in step i) in the inert, particularly aromatic, solvent.

Full Text	Process for preparing sulfuric diamides Description The present invention relates to a process for preparing sulfuric diamides of the general formula I in which R^ and R^ are each independently a primary alkyl radical having from 1 to 8 carbon atoms, a secondary alkyl radical having from 3 to 8 carbon atoms or a cycloalkyi radical having from 5 to 8 carbon atoms, or, together with the nitrogen atom, form a 5- to 8-membered, saturated nitrogen heterocycle which, as well as the nitrogen atom, may have a further heteroatom selected from O and S as a ring member, where the nitrogen heterocycle is unsubstituted or may have 1, 2, 3 or 4 alkyl groups having in each case from 1 to 4 carbon atoms as substituents. Sulfuric diamides of the formula I are interesting intermediates for the preparation of active ingredients, for example for the preparation of the active herbicidal ingredients described in WO01/83459. Processes for preparing sulfuric diamides of the formula I have been known in principle for some time. For instance, R. Behrend, J. Liebigs Ann. Chem. 1884, 222, p. 116-136 describes the preparation of dimethylaminosulfonamide and diethylaminosulfonamide by successive reaction of sulfuryl chloride (SO2CI2) with diethylammonium chloride or diethylammonium chloride and subsequent reaction of the resulting dimethylamido- sulfuryl chloride or diethylamidosulfuryl chloride with gaseous ammonia. However, the reaction proceeds only incompletely. Also disadvantageous is the hydrogen chloride released in the first step. K. W. Wheeler et al., J. Am. Chem. Soc. 1944, 66, p. 1242, describe the preparation of tri- and tetrasubstituted sulfo diamides, in which, in a first step, two equivalents of a secondary amine are first reacted with sulfuryl chloride in substance and the resulting sulfamyl chloride is reacted with two equivalents of a further amine. The yields of this process are unsatisfactory. WO01/83459 describes the preparation of sulfuric diamides of the general formula I by reaction of chlorosulfonamide with a primary or secondary amine. The chlorosulfonamide is prepared by hydrolysis of chlorosulfonyl isocyanate. Chlorosulfonyi isocyanate is, however, comparatively costly. WO03/097589, in turn, describes the preparation of sulfuric diamides of the general M/48074 formula I, in which, in a first step, the chiorosulfonamide of a primary or secondary amine is prepared by successive reaction of the primary or secondary amine with sulfur trioxide in the presence of a tertiary amine, followed by the reaction of the resulting ammonium salt of the corresponding amidosulfonic acid with phosphorus halide. Subsequently, the resulting chiorosulfonamide, also referred to hereinafter as sulfamoyi chloride, is reacted with ammonia. The process is notable for better yields, but is comparatively complicated owing to the multitude of steps. It is thus an object of the present invention to provide an easily performable process for preparing sulfuric diamides of the general formula I designated above, which provides these compounds in good yields and which can be carried out with inexpensive starting materials. This object is surprisingly achieved by the process defined hereinafter. The present invention provides a process for preparing sulfuric diamides of the general formula I designated above, comprising the following steps: 1) the reaction of a secondary amine of the formula II R1R2NH (II) in which R^ and R^ are each as defined above with sulfuryi chloride in an inert solvent, especially an aromatic solvent, in the presence of a tertiary amine to give a sulfamoyi chloride of the formula III R1R2N-S(0)2-CI (III) in which Ri and R^ are each as defined above, and ii) reaction of the sulfamoyi chloride of the formula III obtained in step i) with ammonia, the sulfamoyi chloride of the formula III being used in step ii) in the form of the solution obtained in step i) in the inert solvent, especially the aromatic solvent. The process according to the invention is associated with a series of advantages. Firstly, the process according to the invention is comparatively easy to perform. In addition, it affords the desired sulfuric diamides I in good yields, both based on the secondary amine used and on the sulfuryi chloride used. The release of hydrogen chloride is substantially or even completely avoided. The use of expensive starting materials such as chlorosulfonyl isocyanate is not required. The reaction can additionally be handled efficiently on the industrial scale. Moreover, the sulfuric diamides I are obtained in a purity sufficient for further use, and so it requires no M/48074 complicated purification processes. In step i) of the process according to the invention, a secondary amine of the formula II, as defined above, is reacted with sulfuryl chloride in an inert solvent, especially an aromatic solvent, in the presence of a tertiary amine. This affords a solution of a sulfamoyi chloride of the formula III, also referred to hereinafter as chlorosulfonamide III. The tertiary amine serves as an auxiliary base to bind the hydrogen chloride released in the reaction and is used typically in an amount of at least 0.9 equivalent, preferably in an amount of at least 1.0 equivalent, for example in an amount of from 1.0 to 2 equivalents, and especially in an amount of from 1.05 to 1.5 equivalents, based on the secondary amine. The term "equivalents" is equivalent to the term "mole per mole" or "molar equivalents". The type of tertiary amine is of minor importance for the reaction. Suitable tertiary amines comprise triaikylamines, especially those having from 1 to 6 carbon atoms in the alkyl radicals, N-cycloalkyl-N,N-dialkylamines, especially N-cyclohexyl-N,N- dialkylamines having from 1 to 6 carbon atoms in the alky! radicals, N,N-dialkylanilines having preferably from 1 to 6 carbon atoms in the alkyl radicals, and also pyridine and quinoline bases. Examples of suitable tertiary amines are: from the group of the triaikylamines: trimethylamine, triethylamine, tri-n- propylamine, tri-n-butyiamine, dimethylethylamine, dimethyl-n-propylamine, dimethyl-n-butylamine, dimethylisopropylamine, dimethyl-2-butylamine, diethyl-n-propylamine, diethylisopropylamine, diethyl-n-butylamine, tri-n- hexylamine and the like; from the group of the N-cycloa!kyl-N,N-dialkylamines: dimethylcyclohexylamine and diethylcyclohexylamine; from the group of the N,N-dialkylanilines: dimethylaniline and diethylaniline; from the group of the pyridine and quinoline bases: pyridine, a-,p- and y- picoline, quinoline and isoquinoline. Preferred tertiary amines are triaikylamines and N-cycloalkyl-N,N-dialkylamines, especially tri-Ci-Ce-alkylamines and N-cyclohexyl-N,N-di-Ci-C6-alkylamines. In a particularly preferred embodiment, the tertiary amine used is a tri-Ci-Ce-alkylamine and especially trimethylamine or triethylamine. The process according to the invention is suitable in principle for preparing sulfuric diamides of any secondary aliphatic or cyclic amines. Suitable secondary amines can be described by the general formula II. Preference is given to using those secondary M/48074 4 amines of the formula II in which the R^ and R^ radicals are bonded to the nitrogen atom via a primary carbon atom (CH2 group) or via a secondary carbon atom (CHR, R = alkyl radical). R' and R^ may be primary or secondary alkyl radicals having preferably from 1 to 6 or from 3 to 6 carbon atoms, or a cycloalkyi radical having preferably 5 or 6 carbon atoms. R^ and R^ may be the same or different. R^ and R^ may, hov/ever, together with the nitrogen atom to which they are bonded, also form a 5-, 6-, 7- or 8- membered, saturated nitrogen heterocycle which, as well as the nitrogen atom, may have a further heteroatom selected from O and S as a ring member and which may optionally be substituted, but the a-carbon atoms (the carbon atoms bonded to the nitrogen) are preferably unsubstituted or have one substituent. The expression "primary alkyl radical having from 1 to 8 carbon atoms" represents a saturated linear or branched hydrocarbon radical which has from 1 to 8 and especially from 1 to 6 carbon atoms and is bonded to the nitrogen atom via a CH2 group. Examples of primary alkyl radicals are methyl, ethyl, n-propyi, n-butyl, 2-methylpropyl (isobutyl), n-pentyl, 2-methylbutyl, 3-methylbutyl, n-hexyl, 2-methylpentyl, 3- methylpentyl, 4-methylpentyl, 2-ethylbutyl, etc. The expression "secondary alkyl radical having from 3 to 8 carbon atoms" represents a saturated acyclic hydrocarbon radical which has from 3 to 8 carbon atoms and is bonded via a secondary carbon atom and as nitrogen atom. Examples of secondary alkyl radicals are 2-propyl (1-methylethyl), 2-butyl, 2-pentyl, 3-pentyl, 2-hexyl, 3-hexyl, 3-methyl-2-butyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl etc. In a preferred embodiment of the invention, a secondary amine II in which the two R^ and R2 radicals are different alkyl radicals is used. The same applies to the formulae I and III. More particularly, the R' radical in the formulae I, II and III is a primary alkyl radical having from 1 to 8, in particular having from 1 to 6 and especially having 1 or 2 carbon atoms, or is a secondary alkyl radical having from 3 to 8, in particular from 3 to 6 and especially having 3 or 4 carbon atoms. The R^ radical is especially a secondary alkyl radical having from 3 to 8, in particular from 3 to 6 and especially 3 or 4 carbon atoms. More particularly, R^ is a primary alkyl radical having from 1 to 4 carbon atoms and especially methyl or ethyl, and R^ is a secondary alkyl radical having from 3 to 8, in particular from 3 to 6 and especially 3 or 4 carbon atoms, and is especially isopropyl or 2-butyi. In a very particularly preferred embodiment, a secondary amine of the formula II in which R^ is methyl and in which R^ is a secondary alkyl radical having from 3 to 8, in particular from 3 to 6 and especially 3 or 4 carbon atoms. More particularly, the secondary amine used is N-(1-methylethyl)-N-methylamine (R^ = methyl, R2 = methylethyl = isopropyl). The secondary amine of the formula II and the sulfuryl chloride are preferably used in a molar ratio suitable for the stoichiometry of the reaction, which is preferably in the M/48074 range from 1:1.1 to 1.1:1, in particular in the range from 1:1.05 to 1.05:1 and especially in the range from 1:1.02 to 1.02:1. According to the invention, step i) proceeds in an inert solvent, especially an aromatic solvent. An inert solvent is understood to mean organic solvents which do not enter into any chemical reactions with the reagents, especially with sulfury! chloride, under the reaction conditions. These include especially aromatic, aliphatic, araliphatic and cycloaliphatic hydrocarbons, and also chlorinated and fluorinated hydrocarbons. Nitrogen-containing and/or oxygen-containing solvents are generally not inert, especially when they have OH or NH groups (so-called protic solvents). The proportion of non-inert solvents in the inert solvent is generally not more than 10% by volume, based on the total amount of the solvent. The inert solvent preferably does not comprise any oxygen-containing and/or nitrogen-containing, aprotic solvents ( volume). An "aromatic solvent" is understood to mean those solvents whose main constituents are aromatic compounds which are derived from benzene and are liquid at room temperature. Such compounds include, for example, as well as benzene, alkylbenzenes such as toluene, xylenes, trimethylbenzene and ethylbenzene, and also chlorinated and/or fluorinated benzenes such as chlorobenzene, fluorobenzene and dichlorobenzenes. In addition to these aromatic compounds, the aromatic solvent may also comprise up to 50% by volume, in particular not more than 30% by volume and especially not more than 10% by volume of different inert solvents, for example aliphatic halohydrocarbons, e.g. dichloromethane, trichloromethane and/or dichloroethane, aliphatic or cycloaliphatic hydrocarbons such as n-hexane, n-heptane, octane, cyclohexane, cycloheptane, cyclooctane and mixtures thereof. In addition, the aromatic solvent may also comprise small amounts of non-inert, aprotic oxygen-containing and/or nitrogen- containing solvents, in which case their proportion makes up preferably not more than 10% by volume, based on the total amount of the solvent. The aromatic solvent preferably comprises no oxygen-containing and/or nitrogen-containing, aprotic solvents ( Typically, the secondary amine II is reacted with suifuryl chloride in the substantial or complete absence of protic solvents such as water or alcohols. The proportion of water and protic organic solvents will generally not be more than 0.1% (1000 ppm) and in particular not more than 500 ppm, especially not more than 300 ppm, based on the total amount of solvent used. Preferred aromatic compounds which are useful as aromatic solvents are, as well as benzene, alkylbenzenes such as toluene, xylenes, trimethylbenzene and ethylbenzene, and also chlorinated and/or fluorinated benzenes such as chlorobenzene, fluorobenzene and dichiorobenzenes. In a preferred embodiment, the aromatic solvent comprises chlorobenzene. In particular chlorobenzene forms the main constituent, in particular at least 80%, more preferably at least 90 or at least 95% by volume of the aromatic constituents of the aromatic solvent. In particular, chlorobenzene is the sole constituent and makes up at least 95 and especially at least 98% by volume, based on the total amount of solvent. The reaction of the secondary amine of the formula II with sulfuryl chloride is effected preferably under temperature control and preferably at temperatures of not more than 50°C, in particular not more than 30°C and especially not more than 20°C. The lower limit is generally determined by the melting point of the reaction mixture and the miscibility of the reaction mixture. Frequently, the lower limit in the reaction temperature will not go below -10°C. Frequently, the reaction of the secondary amine II with sulfuryl chloride is carried out at temperatures in the range from -10 to 50°C, in particular in the range from -10 to 30°C and especially in the range from -5 to 20°C. For the reaction of the secondary amine of the formula II with sulfuryl chloride, the procedure will preferably be to initially charge a portion or the total amount of the solvent and sulfuryl chloride in the reaction vessel, to bring the initial charge to the desired reaction temperature and to add the secondary amine II and the tertiary amine thereto. If appropriate, the secondary amine and the tertiary amine can be diluted with the solvent used for the reaction. The secondary amine II and the tertiary amine are preferably added simultaneously, especially as a mixture, such that the prefen-ed molar ratios of secondary amine II and tertiary amine in the reaction mixture are maintained. Since the reaction of sulfuryl chloride with the tertiary amine is exothermic, secondary amine and tertiary amine are preferably added under thermal control over a prolonged period, which is typically at least 20 minutes, in particular at least 30 minutes and especially at least 60 minutes. The maximum addition time is guided by economic considerations and will generally not exceed 15 hours and in particular 8 hours. Frequently, secondary amine II and tertiary amine are added within a period of from one hour to 10 hours and especially over a period of from 2 hours to 8 hours. If appropriate, the reaction can be completed by subjecting the reaction mixture, after the addition of secondary amine II and tertiary amine has ended, to a postreaction, which is typically in the range from 10 minutes to 8 hours and in particular in the range from 30 minutes to 6 hours. The total duration of addition and postreaction phase preferably will not exceed a duration of 15 hours and in particular 10 hours. The concentration of the reactants, i.e. the total amount of sulfuryl chloride, secondary amine II and tertiary amine, is preferably from 10 to 50% by weight and in particular M/48074 from 20 to 40% by weight, based on the total weight of the reaction mixture. In this way, a reaction mixture which comprises the sulfamoyi chloride III dissolved in the solvent is obtained. In addition, the reaction mixture also comprises the salts formed in the reaction, i.e. the hydrogen chloride addition salts of the tertiary amine. The reaction mixture thus obtained can be reacted directly with ammonia in step 11) of the process according to the invention. Preference is given, however, to removing the salts fonned in the reaction by extraction, before the reaction with ammonia in step ii) is performed. The extraction is effected typically under aqueous acidic conditions, i.e. at pH extraction, a dilute acid, especially dilute hydrochloric acid. In particular, dilute hydrochloric acid having a hydrogen chloride content in the range from 2 to 20% by weight and especially in the range from 5 to 15% by weight is used. The extraction can be effected by single or multiple treatment with the dilute aqueous acid. Preference is given to effecting the extraction at temperatures below 30°C and especially below 20°C, for example in the range from 0 to 30°C and especially in the range from 0 to 20°C. The aqueous phase comprising the hydrochloride of the tertiary amine is removed. Any water fractions can be removed by distillation. The distillative removal can be effected at standard pressure and is preferably carried out under reduced pressure. If appropriate, aromatic solvent which has been distilled off will be replaced. The solution of the sulfamoyi chloride of the formula III in the inert solvent thus obtained is reacted with ammonia in step ii). If appropriate, the concentration of sulfamoyi chloride is adjusted by adding further inert, especially aromatic solvents. The concentration of sulfamoyi chloride in the inert solvent in step ii) will preferably be in the range from 5 to 50% by weight, in particular from 10 to 40% by weight and especially from 20 to 30% by weight. The ammonia required for the reaction can be supplied in gaseous form or in the form of a solution, generally a nonaqueous solution. When the ammonia is supplied in the fonn of a solution, the solvent comprises generally less than 1% protic constituents such as water. In a preferred embodiment of the invention, the ammonia is supplied in gaseous form. Preference is then given to performing the reaction in an ammonia atmosphere. The partial pressure of the ammonia in this ammonia atmosphere is typically in the range from 0.5 to 50 bar, in particular in the range from 1 to 30 bar and especially in the range from 2 to 20 bar. If appropriate, the gaseous ammonia can be diluted with a gaseous inert, for example air, nitrogen or argon or a mixture of these gases. The ratio of the partial ammonia pressure to the total partial pressure of all inerts is, however, preferably at least 1:1, in particular at least 5:1 and especially at least 10:1. The total M/48074 pressure of all gaseous constituents will generally not exceed 50 bar, in particular 30 bar and especially 20 bar. In the course of the reaction of the sulfamoyi chloride with ammonia, the partial pressure of the ammonia in the reaction vessel will be kept within the abovementioned ranges. The reaction of the sulfamoyi chloride III with the ammonia is effected typically at temperatures in the range from 10 to lOCC, especially in the range from 30 to 8D°C. The reaction time required for the reaction is generally from 2 to 24 h, especially from 4 to16h. The reaction in step ii) affords a reaction mixture which comprises the sulfuric diamide of the general formula I together with the ammonium chloride formed as a by-product in the reaction in the inert solvent, especially the aromatic solvent. Before a further reaction, the ammonium chloride is generally removed. Since the ammonium chloride is present as a suspended solid in the inert solvent, it can in principle be removed by filtration. Preference is given to removing the ammonium chloride by means of an aqueous extraction. Preference is given to effecting the aqueous extraction at a pH of for the extraction, in particular dilute aqueous hydrochloric acid and especially aqueous hydrochloric acid having a hydrogen chloride content of from 2 to 20% by weight and especially from 5 to 15% by weight. The aqueous extraction of the reaction mixture can be carried out once or more than once. Preference is given to reextracting the combined aqueous extracts once or more than once with a suitable organic solvent in which the sulfuric diamide I is soluble, in particular an aromatic solvent and especially with the inert solvent used for the reaction, especially the aromatic solvent used for the reaction, in order to prevent yield losses. The extracted reaction mixture, if appropriate after combination with the reextracts, comprises the sulfuric diamide I in dissolved form with a purity sufficient for further reactions. The solution can therefore be sent to further reactions as such or after isolation of the sulfuric diamide I. If appropriate, the solution of the sulfuric diamide I will be concentrated by distillation, which likewise removes any water and/or acid present in the solvent. It is also possible to isolate the sulfuric diamide from the solution thus obtained in a customary manner, for example by concentrating to dryness or by crystallization, if appropriate with addition of organic solvents in which the sulfuric diamide I is not soluble. The sulfuric diamides of the general formula I thus obtained can be used especially to prepare active herbicidal ingredients of the general formula IV. In formula, R^ and R2 are each as defined above. R^ is hydrogen or C1-C4-alkyl, R' is hydrogen, C1-C4-alkyl or C1-C4-haloalkyl, X and Y are each hydrogen or halogen, where one of the X or Y radicals may also be CN. Accordingly, the present invention further relates to the use of the process according to the invention for preparing sulfuric diamides of the formula I for the preparation of active herbicidal ingredients of the general fonnula IV. The present invention further provides a process for preparing active herbicidal ingredients of the general formula IV, as described here, comprising the following steps: a) preparation of a sulfuric diamide I by the process described here and in claims 1 to 7, b) reaction of the sulfuric diamide of the formula I with a 3-nitrobenzoyl chloride of the formula V to obtain a 3-nitrobenzenesulfonamide of the formula VI; c) reduction of the 3-nitrobenzenesulfonamide of the formula VI to a 3- aminobenzenesulfonamide of the formula VII d) conversion of the 3-aminobenzenesulfonamide of the formula VII to a compound of the formula IV. In this context, the variables R^ R^, X and Y In the formulae V, VI and VII are each as defined for formula IV. Steps b), c) and d) are known in principle from the prior art. The reaction of the sulfuric diamide of the formula I with a nitrobenzoyi chloride of the formula V can be carried out, for example, according to the in WO 2004/039768 in scheme 2, page 15, and according to the information on pages 16 to 19 or example 1 on page 56 of WO 2004/039768 or according to the examples adduced here. The disclosure on this subject of WO 2004/039768 is hereby fully incorporated by reference. The reduction of the 3-nitrobenzenesulfonamide of the formula VI obtained in step b) to the corresponding 3-aminobenzenesulfonamide of the formula VII can likewise be carried out by the in WO 2004/039768 in reaction scheme 2 on page 15 and according to the information on pages 19 to 22 and 58 to 60 of WO 2004/039768, whose disclosure on this subject is hereby fully incorporated by reference. More particularly, the reduction of the compound VI to the compound VII is carried out by catalytic hydrogenation, as described on pages 21 ff. and 60 of WO 2004/039768, or according to the example of the present application. The subsequent reaction of the 3-aminobenzenesulfonamide of the formula VII to give a compound of the formula IV is likewise known from the prior art, for example from WO 01/83459, WO 2005/054208, WO2006/010474 and WO06/125746. More particularly, the conversion can be carried out in the following manner: reaction of the compound VII with an oxazinone by the method described in the scheme on page 37 of WO 01/83459; by the method described in WO 2006/010474 and WO 06/125746, comprising the following steps: d1) reaction of the 3-aminobenzenesulfonamide of the formula VII with a C1-C4- alkyl chloroformate to give a compound of the formula VIII in which R^ R^, X and Y are each as defined for formula IV and R^ is C1-C4- alkyl, 11 d2) reaction of the compound VIII with a 3-aminoacrylic ester of the formula IX in which R^' is hydrogen or CrC4-alkyl, R' is hydrogen, C1-C4-alkyl or Ci- C4-haloalkyl and R^ is C1-C4-alkyl. d3) When R^' in fonnula IX is hydrogen, after step d2), optional alkylation of the compound IV obtained in step d2), in which R^ is hydrogen, can be carried out with a compound R^^-L in which R^^ is C1-C4-alkyl and L is a nucleophilically displaceable leaving group, e.g. halogen, O-SO2R or OSO2 OR' (R = C1-C4-alkyl, phenyl or tolyl, R' = C1-C4-alkyl). The alkylation can be carried out by the methods described in WO 2006/010474 and WO 06/125746. reaction of the compound VII with phosgene or diphosgene by the method described in WO 2004/039768 to obtain the corresponding isocyanate of the formula X and subsequent reaction of the isocyanate X with a 3-aminoacrylic ester of the formula IX by the method described in WO 2005/054208. The disclosure of these documents is hereby fully incorporated by reference. The following examples serve to illustrate the invention: Example 1: Preparation of N-methyl-N-(1-methylethyl)aminosulfonamide (compound I where Ri=methyl, R2=1-methylethyl) A reaction vessel was initially charged under inert gas atmosphere with 137.7 g (1.0 mol) of sulfuryl chloride in 800 g of chlorobenzene and cooled to internal temperature -5°C. To this were added, over a period of 300 minutes, a mixture of 73.1 g (I.Omol) of isopropylmethylamine and 116.3 g (1.15 mol) of triethylamine, in the course of which the temperature was kept within the range from 0 to 5°C by cooling. After the addition had ended, the resulting suspension was stirred at 10°C for a further 120 minutes. The suspension was then added to 250 g of 10% hydrochloric acid at 10°C. The phases were separated at 10°C and the organic phase was washed again with 250 g of 10% aqueous hydrochloric acid at 10°C. The organic phase was removed and concentrated under reduced pressure (30 mbar, 22 to 4rC), in order to remove water. In this way, 570 g of a solution of N-isopropyl-N-methylsulfamoyI chloride in chlorobenzene (about 25% by weight) were obtained. This corresponds to a yield of 84%. 343.4 g of the solution of N-isopropyl-N-methylsulfamoyI chloride in chlorobenzene (25% strength by weight) obtained in step 1) were introduced into a pressure vessel which was flushed with nitrogen and ammonia. Subsequently, the partial pressure of the ammonia was increased to 5 bar. The reactor contents were then heated to 50°C, and this temperature was maintained for 8 hours, in the course of which an ammonia pressure of 6 bar was maintained. The suspension obtained here was added to 210 g of aqueous hydrochloric acid (8% strength), which dissolved the solids present in the reaction mixture. The pH of the aqueous phase was about 2. The phases were separated at 40°C and the aqueous phase was extracted twice with 372 g of chlorobenzene each time. In this way, 1065 g of a 6.3% by weight solution of the title compound in chlorobenzene was obtained, which corresponds to a yield of 88%. The solution can be used directly in the subsequent reaction. Example 2; Preparation of 2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoro- methyl)-1-(2H)-pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]- benzamide Step b): (2-chloro-4-fluoro-5-nitrobenzoyl)-N'-i-propyl-N'-methylsulfamide To a solution of 43.1 g (0.277 mol) of N-methyl-N-(1-methylethyl)sulfamoylamide and 0.77 g (12.0 mmol) of tributylmethylammonium chloride in 637 g of chlorobenzene were added, at 20°C within 60 min, 43.7 g (50% strength in water) of NaOH. 15 minutes after the start of addition of the base, 65.0 g (0.26 mol) of 2-chloro-4-fluoro-3-nitrobenzoyl chloride in 70 g of chlorobenzene were added within 45 min. Both metered additions ended simultaneously. The reaction mixture was subsequently stirred at 20°C for 1 h and diluted by means of addition of 424 g of water and 138 g of isohexane. The aqueous phase was acidified to pH 4.5 with concentrated hydrochloric acid and then removed at 68-70'C. The organic phase was admixed with 430 g of water and 60 g of isohexane and the phases were separated again at pH 4.5 while hot. The resulting organic phase was admixed with a further 280 g of isohexane and then cooled to 5°C. After filtration, washing with water and drying at 70'C under reduced pressure, 82.1 g (87%) of theory, purity 97%) of N-(2-chloro-4-fluoro-5-nitrobenzoyl)-N'-i-propyl-N'- methylsulfamide were obtained. "¦H NMR (400 MHz, CDCI3) 5 = 9.1 ppm (s, NH), 8.4 (d, Ar-H), 7.45 (d, Ar-H), 4.25 (sept., /Pr-H), 2.95 (s. Me), 1.25 (d, /Pr-H). Step c): N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i-propyl-N'-methylsulfamide 177 g (0.500 mol; 99.9%) of N-(2-chloro-4-fiuoro-3-nitrobenzoyl)-N'-isopropy!-N'- methylsulfamide were admixed in 397 g of methanol witli 2.17 g (0.008 mol%) of 1% Pt/C (63% suspension in water). The mixture was hydrogenated with 5 bar of hydrogen at 60-70°C with stirring. After 2 h, the solution was decompressed, the reaction mixture was filtered at SO'C and the solvent was removed by distillation. 157.8 g (97.5% of theory, purity: 99%) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i-propyl-N'-methylsulf- amide were obtained as a white-yellowish solid (m.p.: 147-149°C). 1H NMR (400 MHz, d-DMSO) 8 =11.9 ppm (s, NH), 7.35 (d, Ar-H), 6.90 (d, Ar-H), 5.50 (br. s., NH2), 4.05 (sept., Pr-H), 2.80 (s, Me), 1.15 (d, /Pr-H). Step d1): N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]-N'-i-propyl-N'-methyl- sulfamide (variant 1) To a solution of 50.0 g (0.153 mol; 99.3%) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i- propyl-N'-methylsulfamide in 225 g of toluene were added, at 105-110°C, 22.7 g (0.207 mol) of ethyl chloroformate and the mixture was subsequently stirred at 108- 110°C for 6.5 h. The reaction mixture was concentrated to dryness on a rotary evaporator under reduced pressure. After drying under reduced pressure at 70°C, 59.9 g (98.4% of theory, purity 99.7%) of N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)- amino}benzoyl]-N'-i-propyl-N'-methylsulfamide were obtained. "¦H NMR (400 MHz, CDCI3) 5 = 8.9 ppm (s, NH), 8.4 (d, Ar-H), 7.2 (d, Ar-H), 6.80 (s, NH), 4.30-4.20 (m, /Pr-H, CHJD), 2.95 (s. Me), 1.40 (q, C/y3CH20), 1.25 (d, Pr-H). Step d 1): N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]-N'-i-propyl-N'-methyl- sulfamide (variant 2) To a solution of 50.0 g (0.153 mol; 99.3%) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i- propyl-N'-methylsulfamide in 450 g of toluene were added, at 105-110°C, 26.9 g (0.245 mol) of ethyl chloroformate and the mixture was then stirred at 108-110°C for 6.5 h. The reaction mixture was concentrated to dryness on a rotary evaporator under reduced pressure. After drying under reduced pressure at 70'C, 61.2 g (99.3% of theory, purity 98.4%) of N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]-N'-i- propyl-N'-methylsulfamide were obtained. Step d2): 2-chloro-5-[3,6-dihydro-2,6-dioxo-4-(trifluoromethyl)-1 (2H)-pyrimidinyl]-4- fluoro-N-{[methyl-(1-methylethyl)amino]sulfonyl}benzamide 396 g (1 mol) of N-(2-chloro-4-fluoro-5-[(ethoxycarbonyl)amino]benzoyl)-N'-isopropyl- N'-methylsulfamide were dissolved at room temperature in 1583 g of DMF, and 189 g (1.02 mol) of ethyl 3-amino-4,4,4-trifluoro-2-butenoate were added. 378 g (2.1 mol) of sodium methoxide solution (30% in methanol) were metered in at 115 - 120°C within 4 h, and methanol and ethanol were distilled off during this time. The mixture was left to stir for a further 30 min. For workup, the reaction mixture was metered with cooling Into dilute sulfuric acid, and, after the end of the addition, the reaction mixture had a pH of filtered off, washed with water and dried. 433 g (89% of theory) of the title compound were obtained [m.p. 238°C (decomposition)]. Stepd3):2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1-(2H)- pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]benzamlde 40.0 g (0.0785 mol) of 2-chloro-5-[3,6-dihydro-2,6-dioxo-4-(trifluoromethyl)-1 (2H)- pyrimidinyi]-4-fluoro-N-{[methyl-(1 -methylethyl)amino]sulfonyl}benzamide, 2.5 g (0.0078 mol) of tetrabutylammonium bromide (= TBAB) and 13.4 g (0.106 mol) of dimethyl sulfate were initially charged at 25°C In a mixture of toluene, water and THF, and the mixture was heated to 40°C. Subsequently, by adding aqueous 10% NaOH solution, a pH of 5.3 - 5.5 was established in the reaction mixture. The mixture was stirred at 40°C for 1 h, in the course of which 10% aqueous NaOH solution continued to be added, such that the pH was constant at the pH established beforehand. After 1 h, the addition of the aqueous 10% NaOH solution was stopped, whereupon the pH fell to 4.4 - 4.5. The mixture was left to stir at a pH of 4.4 - 4.5 and 40°C for a further 5.5 h. After the reaction had ended, the phases were separated, the organic phase was dried and the solvent was partly removed. In the course of cooling, the title compound crystallizes out, and is filtered off, washed with toluene and dried (33 g, 84%). Example 3: Preparation of 2-chloro-5-[3,6-dihydro-3-methyl-2,6-dloxo-4-(trifluoro- methyl)-1-(2H)-pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]- benzamide (variant with performance of steps c) and d1) without intermediate isolation): The preparation was effected analogously to the method for example 2, with the difference that steps c) and d1) were carried out as follows: 179 g (0.500 mol; 99%) of N-(2-chloro-4-fluoro-3-nitrobenzoyl)-N'-isopropyl-N'-methyl- sulfamide were admixed in 391 g of methanol with 4.08 g (0.015 mol%) of 1% Pt/C (63% water) and hydrogenated with 5 bar of hydrogen at 60-70°C with stirring. After 2 h, the solution was decompressed, the reaction mixture was filtered at 60°C and the solution was admixed with 2200 g of toluene. The methanol was removed by distillation together with the water of reaction at 65-68°C while gradually lowering the pressure from 900 mbar to 250 mbar. Subsequently, the suspension of N-(2-chloro-4-fluoro-5- aminobenzoyl)-N'-i-propyl-N'-methylsulfamide in toluene was heated to 106-107°C and admixed with 64.4 g (0.588 mol) of ethyl chloroformate within 10 min. The mixture was subsequently stirred at 110°C for 6.5 h. Subsequently, 746 g of toluene were distilled off at standard pressure and the mixture was then cooled to internal temperature S'C. After the product solution had been seeded with 150 mg of the target compound, the product crystallized at 5°C within 60 min. After filtration and drying under reduced pressure at 70°C, 166.2 g (95.0% of theory, purity 98.5%) of N-[2-chloro-4-fIuoro-5- {(ethoxycarbonyl)amino}benzoyl]amino}benzoyl]-N'-i-propyl-N'-methylsulfamide were obtained. Example 4: Preparation of 2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoro- methyl)-1-(2H)-pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]- benzamide (variant with crystallization of the product obtained in d1)) The preparation was effected analogously to the method for example 2, with the difference that step d1) was carried out as follows: To a solution of 150.9 g (0.466 mol) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i- propyl-N'-methylsulfamide in 350 g of methanol and 18.4 g of water were added 1100 g of toluene. The methanol was removed by distillation together with the water at 65- 68°C while gradually lowering the pressure from 900 mbar to 250 mbar. Subsequently, the suspension of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i-propyl-N'-methylsulfamide in toluene was heated to 108-109'C, then admixed with 64.4 g (0.588 mol) of ethyl chloroformate within 10 min and subsequently stirred at 110°C for 6.5 h. After the product solution had been seeded with 100 mg of the target compound, the product crystallized at 5°C within 60 min. After filtration and drying at 70°C under reduced pressure, 169.6 g (92.0% of theory, purity 99.7%) of N-[2-chloro-4-fluoro-5- {(ethoxycarbonyl)amino}benzoyl]amino}benzoyl]-N'-i-propyl-N'-methylsulfamidewere obtained. Claims: 1. A process for preparing sulfuric diamides of the formula I R1R2N-S(0)2-NH2 (I) in which R' and R^ are each independently a primary alkyl radical having from 1 to 8 carbon atoms, a secondary alkyl radical having from 3 to 8 carbon atoms or a cycloalkyi radical having from 5 to 8 carbon atoms, or, together with the nitrogen atom, form a 5- to 8-membered, saturated nitrogen heterocycle which, as well as the nitrogen atom, may have a further heteroatom selected from O and S as a ring member, where the nitrogen heterocycle may have 1, 2, 3 or 4 alkyl groups having in each case from 1 to 4 carbon atoms as substituents, comprising i) the reaction of a secondary amine of the formula II R1R2NH (II) in which R^ and R^ are each as defined above with sulfuryl chloride in an inert organic solvent in the presence of a tertiary amine to give a sulfamoyi chloride of the formula III R1R2N-S(0)2-CI (III) in which R' and R^ are each as defined above, and ii) reaction of the sulfamoyi chloride of the formula III obtained in step i) with ammonia, the sulfamoyi chloride of the formula III being used in step ii) in the form of the solution obtained in step i) in the inert organic solvent. 2. The process according to claim 1, wherein step i) comprises an extractive removal of the salts formed in the reaction, 3. The process according to claim 1 or 2, wherein tertiary amine is used in an amount of from 1.05 to 1.5 equivalents, based on the secondary amine. 4. The process according to any one of the preceding claims, wherein the tertiary amine is a tri-Ci-Ce-alkylamine. 5. The process according to any one of the preceding claims, wherein the R^ radical M/48074 in the formuiae I, II and III is a primary alkyl radical having from 1 to 8 carbon atoms or a secondary alkyl radical having from 3 to 8 carbon atoms and the R^ radicals are each a secondary alkyl radical having from 3 to 8 carbon atoms. 6. The process according to claim 5, wherein the secondary amine of the formula used is N-(1-methylethyl)-N-methylamine. 7. The process according to any one of the preceding claims, wherein the secondary amine of the formula II and sulfuryl chloride are used in step i) in a molar ratio of from 1:1.1 to 1.1:1. 8. The process according to any one of the preceding claims, wherein the inert organic solvent is an aromatic solvent. 9. The process according to claim 8, wherein the aromatic solvent comprises chlorobenzene. 10. The process according to any one of the preceding claims, wherein gaseous ammonia is used in step ii). 11. A process for preparing active herbicidal ingredients of the general formula IV in which R^ and R2 are each as defined above, R^ is hydrogen or C1-C4-alkyl, R" is hydrogen, C1-C4-alkyl or CrC4-haloalkyl, X and Y are each hydrogen or halogen, where one of the X or Y radicals may also be CN, comprising a) preparation of a sulfuric diamide I by a process according to any one of claims 1 to 7, b) reaction of the sulfuric diamide of the formula I with a S-nitrobenzoyI formula VI; c) reduction of the 3-nitrobenzenesulfonamide of the formuia VI to a 3- aminobenzenesulfonamide of the formula VII d) conversion of the 3-aminobenzenesulfonamide of the formula VII to a compound of the formula IV, where the variables R^ R^, X and Y in the formulae V, VI and VII are each as defined for formula IV. 12. The process according to claim 11, wherein step d) comprises the following steps: d1) reaction of the 3-aminobenzenesulfonamide of the formula Vil with a Ct-C4- alkyl chloroformate to give a compound of the formula VIII in which R\ R^, X and Y are each as defined for formula IV and R^ is C1-C4- alkyl, d2) reaction of the compound VIII with a 3-aminoacrylic ester of the formula IX in which R3' is hydrogen or C1-C4-alkyl, R' is hydrogen, C1-C4-alkyl or Ci- C4-haloalkyl and R" is C1-C4-alkyl, and M/48074 d3) when Ra is hydrogen, optional alkylation of the compound IV obtained in step d2), in which Ra is hydrogen, with a compound Raa-L in which Raa is C1-C4-alkyl and L is a nucleophilically displaceable leaving group, to obtain a compound of the general formula IV. The present invention relates to a method for producing sulfonic acid amines of the general formula (I) R1R2N- S(O)2-NH2 (I), where R and R are independent of each other and stand for a primary alkyl radical having 1 to 8 C atoms, a secondary alkyl radical having 3 to 8 C atoms, or a cycloalkyl radical having 5 to 8 C atoms, or, together with the nitrogen atom, form a 5- to 8-member saturated nitrogen heterocyclic compound that can comprise, in addition to the nitrogen atom, an additional hetero atom, selected from O and S, as a ring member, wherein the nitrogen heterocyclic compound is unsubstituted, or can comprise 1, 2, 3, or 4 alkyl groups each having 1 to 4 C atoms as substituents. The method comprises the following steps: i) conversion of a secondary amine of the formula (II) R1R2NH (II), where R and R have the meaning indicated above, having sulfuryl chloride in an inert, particularly aromatic, solvent in the presence of a tertiary amine, to form a sulfamoyl chloride of the formula (III) R1R2N-S(O)2-CI (III), where R1 and R2 have the meaning indicated above, and ii) conversion of the sulfamoyl chloride of the formula (III) obtained in step i) using ammonia, wherein in step ii) the sulfamoyl chloride of the formula (III) is used in the form of the solution obtained in step i) in the inert, particularly aromatic, solvent.

Full Text

Process for preparing sulfuric diamides
Description
The present invention relates to a process for preparing sulfuric diamides of the
general formula I

in which R^ and R^ are each independently a primary alkyl radical having from 1 to 8
carbon atoms, a secondary alkyl radical having from 3 to 8 carbon atoms or a
cycloalkyi radical having from 5 to 8 carbon atoms, or, together with the nitrogen atom,
form a 5- to 8-membered, saturated nitrogen heterocycle which, as well as the nitrogen
atom, may have a further heteroatom selected from O and S as a ring member, where
the nitrogen heterocycle is unsubstituted or may have 1, 2, 3 or 4 alkyl groups having in
each case from 1 to 4 carbon atoms as substituents.
Sulfuric diamides of the formula I are interesting intermediates for the preparation of
active ingredients, for example for the preparation of the active herbicidal ingredients
described in WO01/83459.
Processes for preparing sulfuric diamides of the formula I have been known in principle
for some time. For instance, R. Behrend, J. Liebigs Ann. Chem. 1884, 222, p. 116-136
describes the preparation of dimethylaminosulfonamide and diethylaminosulfonamide
by successive reaction of sulfuryl chloride (SO2CI2) with diethylammonium chloride or
diethylammonium chloride and subsequent reaction of the resulting dimethylamido-
sulfuryl chloride or diethylamidosulfuryl chloride with gaseous ammonia. However, the
reaction proceeds only incompletely. Also disadvantageous is the hydrogen chloride
released in the first step.
K. W. Wheeler et al., J. Am. Chem. Soc. 1944, 66, p. 1242, describe the preparation of
tri- and tetrasubstituted sulfo diamides, in which, in a first step, two equivalents of a
secondary amine are first reacted with sulfuryl chloride in substance and the resulting
sulfamyl chloride is reacted with two equivalents of a further amine. The yields of this
process are unsatisfactory.
WO01/83459 describes the preparation of sulfuric diamides of the general formula I by
reaction of chlorosulfonamide with a primary or secondary amine. The
chlorosulfonamide is prepared by hydrolysis of chlorosulfonyl isocyanate.
Chlorosulfonyi isocyanate is, however, comparatively costly.
WO03/097589, in turn, describes the preparation of sulfuric diamides of the general
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formula I, in which, in a first step, the chiorosulfonamide of a primary or secondary
amine is prepared by successive reaction of the primary or secondary amine with sulfur
trioxide in the presence of a tertiary amine, followed by the reaction of the resulting
ammonium salt of the corresponding amidosulfonic acid with phosphorus halide.
Subsequently, the resulting chiorosulfonamide, also referred to hereinafter as sulfamoyi
chloride, is reacted with ammonia. The process is notable for better yields, but is
comparatively complicated owing to the multitude of steps.
It is thus an object of the present invention to provide an easily performable process for
preparing sulfuric diamides of the general formula I designated above, which provides
these compounds in good yields and which can be carried out with inexpensive starting
materials. This object is surprisingly achieved by the process defined hereinafter.
The present invention provides a process for preparing sulfuric diamides of the general
formula I designated above, comprising the following steps:
1) the reaction of a secondary amine of the formula II
R1R2NH (II)
in which R^ and R^ are each as defined above with sulfuryi chloride in an inert
solvent, especially an aromatic solvent, in the presence of a tertiary amine to give
a sulfamoyi chloride of the formula III
R1R2N-S(0)2-CI (III)
in which Ri and R^ are each as defined above, and
ii) reaction of the sulfamoyi chloride of the formula III obtained in step i) with
ammonia,
the sulfamoyi chloride of the formula III being used in step ii) in the form of the solution
obtained in step i) in the inert solvent, especially the aromatic solvent.
The process according to the invention is associated with a series of advantages.
Firstly, the process according to the invention is comparatively easy to perform. In
addition, it affords the desired sulfuric diamides I in good yields, both based on the
secondary amine used and on the sulfuryi chloride used. The release of hydrogen
chloride is substantially or even completely avoided. The use of expensive starting
materials such as chlorosulfonyl isocyanate is not required. The reaction can
additionally be handled efficiently on the industrial scale. Moreover, the sulfuric
diamides I are obtained in a purity sufficient for further use, and so it requires no
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complicated purification processes.
In step i) of the process according to the invention, a secondary amine of the formula II,
as defined above, is reacted with sulfuryl chloride in an inert solvent, especially an
aromatic solvent, in the presence of a tertiary amine. This affords a solution of a
sulfamoyi chloride of the formula III, also referred to hereinafter as chlorosulfonamide
III.
The tertiary amine serves as an auxiliary base to bind the hydrogen chloride released
in the reaction and is used typically in an amount of at least 0.9 equivalent, preferably
in an amount of at least 1.0 equivalent, for example in an amount of from 1.0 to 2
equivalents, and especially in an amount of from 1.05 to 1.5 equivalents, based on the
secondary amine. The term "equivalents" is equivalent to the term "mole per mole" or
"molar equivalents".
The type of tertiary amine is of minor importance for the reaction. Suitable tertiary
amines comprise triaikylamines, especially those having from 1 to 6 carbon atoms in
the alkyl radicals, N-cycloalkyl-N,N-dialkylamines, especially N-cyclohexyl-N,N-
dialkylamines having from 1 to 6 carbon atoms in the alky! radicals, N,N-dialkylanilines
having preferably from 1 to 6 carbon atoms in the alkyl radicals, and also pyridine and
quinoline bases.
Examples of suitable tertiary amines are:
from the group of the triaikylamines: trimethylamine, triethylamine, tri-n-
propylamine, tri-n-butyiamine, dimethylethylamine, dimethyl-n-propylamine,
dimethyl-n-butylamine, dimethylisopropylamine, dimethyl-2-butylamine,
diethyl-n-propylamine, diethylisopropylamine, diethyl-n-butylamine, tri-n-
hexylamine and the like;
from the group of the N-cycloa!kyl-N,N-dialkylamines:
dimethylcyclohexylamine and diethylcyclohexylamine;
from the group of the N,N-dialkylanilines: dimethylaniline and diethylaniline;
from the group of the pyridine and quinoline bases: pyridine, a-,p- and y-
picoline, quinoline and isoquinoline.
Preferred tertiary amines are triaikylamines and N-cycloalkyl-N,N-dialkylamines,
especially tri-Ci-Ce-alkylamines and N-cyclohexyl-N,N-di-Ci-C6-alkylamines. In a
particularly preferred embodiment, the tertiary amine used is a tri-Ci-Ce-alkylamine and
especially trimethylamine or triethylamine.
The process according to the invention is suitable in principle for preparing sulfuric
diamides of any secondary aliphatic or cyclic amines. Suitable secondary amines can
be described by the general formula II. Preference is given to using those secondary
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4
amines of the formula II in which the R^ and R^ radicals are bonded to the nitrogen
atom via a primary carbon atom (CH2 group) or via a secondary carbon atom (CHR, R
= alkyl radical). R' and R^ may be primary or secondary alkyl radicals having preferably
from 1 to 6 or from 3 to 6 carbon atoms, or a cycloalkyi radical having preferably 5 or 6
carbon atoms. R^ and R^ may be the same or different. R^ and R^ may, hov/ever,
together with the nitrogen atom to which they are bonded, also form a 5-, 6-, 7- or 8-
membered, saturated nitrogen heterocycle which, as well as the nitrogen atom, may
have a further heteroatom selected from O and S as a ring member and which may
optionally be substituted, but the a-carbon atoms (the carbon atoms bonded to the
nitrogen) are preferably unsubstituted or have one substituent.
The expression "primary alkyl radical having from 1 to 8 carbon atoms" represents a
saturated linear or branched hydrocarbon radical which has from 1 to 8 and especially
from 1 to 6 carbon atoms and is bonded to the nitrogen atom via a CH2 group.
Examples of primary alkyl radicals are methyl, ethyl, n-propyi, n-butyl, 2-methylpropyl
(isobutyl), n-pentyl, 2-methylbutyl, 3-methylbutyl, n-hexyl, 2-methylpentyl, 3-
methylpentyl, 4-methylpentyl, 2-ethylbutyl, etc.
The expression "secondary alkyl radical having from 3 to 8 carbon atoms" represents a
saturated acyclic hydrocarbon radical which has from 3 to 8 carbon atoms and is
bonded via a secondary carbon atom and as nitrogen atom. Examples of secondary
alkyl radicals are 2-propyl (1-methylethyl), 2-butyl, 2-pentyl, 3-pentyl, 2-hexyl, 3-hexyl,
3-methyl-2-butyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl etc.
In a preferred embodiment of the invention, a secondary amine II in which the two R^
and R2 radicals are different alkyl radicals is used. The same applies to the formulae I
and III. More particularly, the R' radical in the formulae I, II and III is a primary alkyl
radical having from 1 to 8, in particular having from 1 to 6 and especially having 1 or 2
carbon atoms, or is a secondary alkyl radical having from 3 to 8, in particular from 3 to
6 and especially having 3 or 4 carbon atoms. The R^ radical is especially a secondary
alkyl radical having from 3 to 8, in particular from 3 to 6 and especially 3 or 4 carbon
atoms. More particularly, R^ is a primary alkyl radical having from 1 to 4 carbon atoms
and especially methyl or ethyl, and R^ is a secondary alkyl radical having from 3 to 8, in
particular from 3 to 6 and especially 3 or 4 carbon atoms, and is especially isopropyl or
2-butyi. In a very particularly preferred embodiment, a secondary amine of the formula
II in which R^ is methyl and in which R^ is a secondary alkyl radical having from 3 to 8,
in particular from 3 to 6 and especially 3 or 4 carbon atoms. More particularly, the
secondary amine used is N-(1-methylethyl)-N-methylamine (R^ = methyl, R2 =
methylethyl = isopropyl).
The secondary amine of the formula II and the sulfuryl chloride are preferably used in a
molar ratio suitable for the stoichiometry of the reaction, which is preferably in the
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range from 1:1.1 to 1.1:1, in particular in the range from 1:1.05 to 1.05:1 and especially
in the range from 1:1.02 to 1.02:1.
According to the invention, step i) proceeds in an inert solvent, especially an aromatic
solvent.
An inert solvent is understood to mean organic solvents which do not enter into any
chemical reactions with the reagents, especially with sulfury! chloride, under the
reaction conditions. These include especially aromatic, aliphatic, araliphatic and
cycloaliphatic hydrocarbons, and also chlorinated and fluorinated hydrocarbons.
Nitrogen-containing and/or oxygen-containing solvents are generally not inert,
especially when they have OH or NH groups (so-called protic solvents). The proportion
of non-inert solvents in the inert solvent is generally not more than 10% by volume,
based on the total amount of the solvent. The inert solvent preferably does not
comprise any oxygen-containing and/or nitrogen-containing, aprotic solvents ( volume).
An "aromatic solvent" is understood to mean those solvents whose main constituents
are aromatic compounds which are derived from benzene and are liquid at room
temperature. Such compounds include, for example, as well as benzene,
alkylbenzenes such as toluene, xylenes, trimethylbenzene and ethylbenzene, and also
chlorinated and/or fluorinated benzenes such as chlorobenzene, fluorobenzene and
dichlorobenzenes.
In addition to these aromatic compounds, the aromatic solvent may also comprise up to
50% by volume, in particular not more than 30% by volume and especially not more
than 10% by volume of different inert solvents, for example aliphatic halohydrocarbons,
e.g. dichloromethane, trichloromethane and/or dichloroethane, aliphatic or
cycloaliphatic hydrocarbons such as n-hexane, n-heptane, octane, cyclohexane,
cycloheptane, cyclooctane and mixtures thereof. In addition, the aromatic solvent may
also comprise small amounts of non-inert, aprotic oxygen-containing and/or nitrogen-
containing solvents, in which case their proportion makes up preferably not more than
10% by volume, based on the total amount of the solvent. The aromatic solvent
preferably comprises no oxygen-containing and/or nitrogen-containing, aprotic solvents
( Typically, the secondary amine II is reacted with suifuryl chloride in the substantial or
complete absence of protic solvents such as water or alcohols. The proportion of water
and protic organic solvents will generally not be more than 0.1% (1000 ppm) and in
particular not more than 500 ppm, especially not more than 300 ppm, based on the
total amount of solvent used.

Preferred aromatic compounds which are useful as aromatic solvents are, as well as
benzene, alkylbenzenes such as toluene, xylenes, trimethylbenzene and ethylbenzene,
and also chlorinated and/or fluorinated benzenes such as chlorobenzene,
fluorobenzene and dichiorobenzenes. In a preferred embodiment, the aromatic solvent
comprises chlorobenzene. In particular chlorobenzene forms the main constituent, in
particular at least 80%, more preferably at least 90 or at least 95% by volume of the
aromatic constituents of the aromatic solvent. In particular, chlorobenzene is the sole
constituent and makes up at least 95 and especially at least 98% by volume, based on
the total amount of solvent.
The reaction of the secondary amine of the formula II with sulfuryl chloride is effected
preferably under temperature control and preferably at temperatures of not more than
50°C, in particular not more than 30°C and especially not more than 20°C. The lower
limit is generally determined by the melting point of the reaction mixture and the
miscibility of the reaction mixture. Frequently, the lower limit in the reaction temperature
will not go below -10°C. Frequently, the reaction of the secondary amine II with sulfuryl
chloride is carried out at temperatures in the range from -10 to 50°C, in particular in the
range from -10 to 30°C and especially in the range from -5 to 20°C.
For the reaction of the secondary amine of the formula II with sulfuryl chloride, the
procedure will preferably be to initially charge a portion or the total amount of the
solvent and sulfuryl chloride in the reaction vessel, to bring the initial charge to the
desired reaction temperature and to add the secondary amine II and the tertiary amine
thereto. If appropriate, the secondary amine and the tertiary amine can be diluted with
the solvent used for the reaction. The secondary amine II and the tertiary amine are
preferably added simultaneously, especially as a mixture, such that the prefen-ed molar
ratios of secondary amine II and tertiary amine in the reaction mixture are maintained.
Since the reaction of sulfuryl chloride with the tertiary amine is exothermic, secondary
amine and tertiary amine are preferably added under thermal control over a prolonged
period, which is typically at least 20 minutes, in particular at least 30 minutes and
especially at least 60 minutes. The maximum addition time is guided by economic
considerations and will generally not exceed 15 hours and in particular 8 hours.
Frequently, secondary amine II and tertiary amine are added within a period of from
one hour to 10 hours and especially over a period of from 2 hours to 8 hours. If
appropriate, the reaction can be completed by subjecting the reaction mixture, after the
addition of secondary amine II and tertiary amine has ended, to a postreaction, which is
typically in the range from 10 minutes to 8 hours and in particular in the range from 30
minutes to 6 hours. The total duration of addition and postreaction phase preferably will
not exceed a duration of 15 hours and in particular 10 hours.
The concentration of the reactants, i.e. the total amount of sulfuryl chloride, secondary
amine II and tertiary amine, is preferably from 10 to 50% by weight and in particular
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from 20 to 40% by weight, based on the total weight of the reaction mixture.
In this way, a reaction mixture which comprises the sulfamoyi chloride III dissolved in
the solvent is obtained. In addition, the reaction mixture also comprises the salts
formed in the reaction, i.e. the hydrogen chloride addition salts of the tertiary amine.
The reaction mixture thus obtained can be reacted directly with ammonia in step 11) of
the process according to the invention. Preference is given, however, to removing the
salts fonned in the reaction by extraction, before the reaction with ammonia in step ii) is
performed. The extraction is effected typically under aqueous acidic conditions, i.e. at
pH extraction, a dilute acid, especially dilute hydrochloric acid. In particular, dilute
hydrochloric acid having a hydrogen chloride content in the range from 2 to 20% by
weight and especially in the range from 5 to 15% by weight is used. The extraction can
be effected by single or multiple treatment with the dilute aqueous acid. Preference is
given to effecting the extraction at temperatures below 30°C and especially below
20°C, for example in the range from 0 to 30°C and especially in the range from 0 to
20°C. The aqueous phase comprising the hydrochloride of the tertiary amine is
removed. Any water fractions can be removed by distillation. The distillative removal
can be effected at standard pressure and is preferably carried out under reduced
pressure. If appropriate, aromatic solvent which has been distilled off will be replaced.
The solution of the sulfamoyi chloride of the formula III in the inert solvent thus
obtained is reacted with ammonia in step ii). If appropriate, the concentration of
sulfamoyi chloride is adjusted by adding further inert, especially aromatic solvents. The
concentration of sulfamoyi chloride in the inert solvent in step ii) will preferably be in the
range from 5 to 50% by weight, in particular from 10 to 40% by weight and especially
from 20 to 30% by weight.
The ammonia required for the reaction can be supplied in gaseous form or in the form
of a solution, generally a nonaqueous solution. When the ammonia is supplied in the
fonn of a solution, the solvent comprises generally less than 1% protic constituents
such as water.
In a preferred embodiment of the invention, the ammonia is supplied in gaseous form.
Preference is then given to performing the reaction in an ammonia atmosphere. The
partial pressure of the ammonia in this ammonia atmosphere is typically in the range
from 0.5 to 50 bar, in particular in the range from 1 to 30 bar and especially in the
range from 2 to 20 bar. If appropriate, the gaseous ammonia can be diluted with a
gaseous inert, for example air, nitrogen or argon or a mixture of these gases. The ratio
of the partial ammonia pressure to the total partial pressure of all inerts is, however,
preferably at least 1:1, in particular at least 5:1 and especially at least 10:1. The total
M/48074

pressure of all gaseous constituents will generally not exceed 50 bar, in particular
30 bar and especially 20 bar. In the course of the reaction of the sulfamoyi chloride with
ammonia, the partial pressure of the ammonia in the reaction vessel will be kept within
the abovementioned ranges.
The reaction of the sulfamoyi chloride III with the ammonia is effected typically at
temperatures in the range from 10 to lOCC, especially in the range from 30 to 8D°C.
The reaction time required for the reaction is generally from 2 to 24 h, especially from 4
to16h.
The reaction in step ii) affords a reaction mixture which comprises the sulfuric diamide
of the general formula I together with the ammonium chloride formed as a by-product in
the reaction in the inert solvent, especially the aromatic solvent. Before a further
reaction, the ammonium chloride is generally removed. Since the ammonium chloride
is present as a suspended solid in the inert solvent, it can in principle be removed by
filtration. Preference is given to removing the ammonium chloride by means of an
aqueous extraction. Preference is given to effecting the aqueous extraction at a pH of
for the extraction, in particular dilute aqueous hydrochloric acid and especially aqueous
hydrochloric acid having a hydrogen chloride content of from 2 to 20% by weight and
especially from 5 to 15% by weight. The aqueous extraction of the reaction mixture can
be carried out once or more than once.
Preference is given to reextracting the combined aqueous extracts once or more than
once with a suitable organic solvent in which the sulfuric diamide I is soluble, in
particular an aromatic solvent and especially with the inert solvent used for the
reaction, especially the aromatic solvent used for the reaction, in order to prevent yield
losses. The extracted reaction mixture, if appropriate after combination with the
reextracts, comprises the sulfuric diamide I in dissolved form with a purity sufficient for
further reactions. The solution can therefore be sent to further reactions as such or
after isolation of the sulfuric diamide I. If appropriate, the solution of the sulfuric diamide
I will be concentrated by distillation, which likewise removes any water and/or acid
present in the solvent. It is also possible to isolate the sulfuric diamide from the solution
thus obtained in a customary manner, for example by concentrating to dryness or by
crystallization, if appropriate with addition of organic solvents in which the sulfuric
diamide I is not soluble.
The sulfuric diamides of the general formula I thus obtained can be used especially to
prepare active herbicidal ingredients of the general formula IV.
In formula, R^ and R2 are each as defined above. R^ is hydrogen or C1-C4-alkyl, R' is
hydrogen, C1-C4-alkyl or C1-C4-haloalkyl, X and Y are each hydrogen or halogen,
where one of the X or Y radicals may also be CN.
Accordingly, the present invention further relates to the use of the process according to
the invention for preparing sulfuric diamides of the formula I for the preparation of
active herbicidal ingredients of the general fonnula IV.
The present invention further provides a process for preparing active herbicidal
ingredients of the general formula IV, as described here, comprising the following
steps:
a) preparation of a sulfuric diamide I by the process described here and in claims 1
to 7,
b) reaction of the sulfuric diamide of the formula I with a 3-nitrobenzoyl chloride of
the formula V to obtain a 3-nitrobenzenesulfonamide of the formula VI;

c) reduction of the 3-nitrobenzenesulfonamide of the formula VI to a 3-
aminobenzenesulfonamide of the formula VII

d) conversion of the 3-aminobenzenesulfonamide of the formula VII to a compound
of the formula IV.

In this context, the variables R^ R^, X and Y In the formulae V, VI and VII are each as
defined for formula IV.
Steps b), c) and d) are known in principle from the prior art.
The reaction of the sulfuric diamide of the formula I with a nitrobenzoyi chloride of the
formula V can be carried out, for example, according to the in WO 2004/039768 in
scheme 2, page 15, and according to the information on pages 16 to 19 or example 1
on page 56 of WO 2004/039768 or according to the examples adduced here. The
disclosure on this subject of WO 2004/039768 is hereby fully incorporated by
reference.
The reduction of the 3-nitrobenzenesulfonamide of the formula VI obtained in step b) to
the corresponding 3-aminobenzenesulfonamide of the formula VII can likewise be
carried out by the in WO 2004/039768 in reaction scheme 2 on page 15 and according
to the information on pages 19 to 22 and 58 to 60 of WO 2004/039768, whose
disclosure on this subject is hereby fully incorporated by reference. More particularly,
the reduction of the compound VI to the compound VII is carried out by catalytic
hydrogenation, as described on pages 21 ff. and 60 of WO 2004/039768, or according
to the example of the present application.
The subsequent reaction of the 3-aminobenzenesulfonamide of the formula VII to give
a compound of the formula IV is likewise known from the prior art, for example from
WO 01/83459, WO 2005/054208, WO2006/010474 and WO06/125746. More
particularly, the conversion can be carried out in the following manner:
reaction of the compound VII with an oxazinone by the method described in the
scheme on page 37 of WO 01/83459;
by the method described in WO 2006/010474 and WO 06/125746, comprising
the following steps:
d1) reaction of the 3-aminobenzenesulfonamide of the formula VII with a C1-C4-
alkyl chloroformate to give a compound of the formula VIII

in which R^ R^, X and Y are each as defined for formula IV and R^ is C1-C4-
alkyl,

11
d2) reaction of the compound VIII with a 3-aminoacrylic ester of the formula IX

in which R^' is hydrogen or CrC4-alkyl, R' is hydrogen, C1-C4-alkyl or Ci-
C4-haloalkyl and R^ is C1-C4-alkyl.
d3) When R^' in fonnula IX is hydrogen, after step d2), optional alkylation of the
compound IV obtained in step d2), in which R^ is hydrogen, can be carried
out with a compound R^^-L in which R^^ is C1-C4-alkyl and L is a
nucleophilically displaceable leaving group, e.g. halogen, O-SO2R or OSO2
OR' (R = C1-C4-alkyl, phenyl or tolyl, R' = C1-C4-alkyl). The alkylation can be
carried out by the methods described in WO 2006/010474 and WO
06/125746.
reaction of the compound VII with phosgene or diphosgene by the method
described in WO 2004/039768 to obtain the corresponding isocyanate of the
formula X
and subsequent reaction of the isocyanate X with a 3-aminoacrylic ester of the
formula IX by the method described in WO 2005/054208.
The disclosure of these documents is hereby fully incorporated by reference.
The following examples serve to illustrate the invention:
Example 1:
Preparation of N-methyl-N-(1-methylethyl)aminosulfonamide (compound I where
Ri=methyl, R2=1-methylethyl)
A reaction vessel was initially charged under inert gas atmosphere with 137.7 g
(1.0 mol) of sulfuryl chloride in 800 g of chlorobenzene and cooled to internal
temperature -5°C. To this were added, over a period of 300 minutes, a mixture of
73.1 g (I.Omol) of isopropylmethylamine and 116.3 g (1.15 mol) of triethylamine, in the
course of which the temperature was kept within the range from 0 to 5°C by cooling.
After the addition had ended, the resulting suspension was stirred at 10°C for a further
120 minutes. The suspension was then added to 250 g of 10% hydrochloric acid at
10°C. The phases were separated at 10°C and the organic phase was washed again

with 250 g of 10% aqueous hydrochloric acid at 10°C. The organic phase was removed
and concentrated under reduced pressure (30 mbar, 22 to 4rC), in order to remove
water. In this way, 570 g of a solution of N-isopropyl-N-methylsulfamoyI chloride in
chlorobenzene (about 25% by weight) were obtained. This corresponds to a yield of
84%.
343.4 g of the solution of N-isopropyl-N-methylsulfamoyI chloride in chlorobenzene
(25% strength by weight) obtained in step 1) were introduced into a pressure vessel
which was flushed with nitrogen and ammonia. Subsequently, the partial pressure of
the ammonia was increased to 5 bar. The reactor contents were then heated to 50°C,
and this temperature was maintained for 8 hours, in the course of which an ammonia
pressure of 6 bar was maintained. The suspension obtained here was added to 210 g
of aqueous hydrochloric acid (8% strength), which dissolved the solids present in the
reaction mixture. The pH of the aqueous phase was about 2. The phases were
separated at 40°C and the aqueous phase was extracted twice with 372 g of
chlorobenzene each time. In this way, 1065 g of a 6.3% by weight solution of the title
compound in chlorobenzene was obtained, which corresponds to a yield of 88%. The
solution can be used directly in the subsequent reaction.
Example 2; Preparation of 2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoro-
methyl)-1-(2H)-pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]-
benzamide
Step b): (2-chloro-4-fluoro-5-nitrobenzoyl)-N'-i-propyl-N'-methylsulfamide
To a solution of 43.1 g (0.277 mol) of N-methyl-N-(1-methylethyl)sulfamoylamide and
0.77 g (12.0 mmol) of tributylmethylammonium chloride in 637 g of chlorobenzene were
added, at 20°C within 60 min, 43.7 g (50% strength in water) of NaOH. 15 minutes after
the start of addition of the base, 65.0 g (0.26 mol) of 2-chloro-4-fluoro-3-nitrobenzoyl
chloride in 70 g of chlorobenzene were added within 45 min. Both metered additions
ended simultaneously. The reaction mixture was subsequently stirred at 20°C for 1 h
and diluted by means of addition of 424 g of water and 138 g of isohexane. The
aqueous phase was acidified to pH 4.5 with concentrated hydrochloric acid and then
removed at 68-70'C. The organic phase was admixed with 430 g of water and 60 g of
isohexane and the phases were separated again at pH 4.5 while hot. The resulting
organic phase was admixed with a further 280 g of isohexane and then cooled to 5°C.
After filtration, washing with water and drying at 70'C under reduced pressure, 82.1 g
(87%) of theory, purity 97%) of N-(2-chloro-4-fluoro-5-nitrobenzoyl)-N'-i-propyl-N'-
methylsulfamide were obtained.
"¦H NMR (400 MHz, CDCI3) 5 = 9.1 ppm (s, NH), 8.4 (d, Ar-H), 7.45 (d, Ar-H), 4.25
(sept., /Pr-H), 2.95 (s. Me), 1.25 (d, /Pr-H).

Step c): N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i-propyl-N'-methylsulfamide
177 g (0.500 mol; 99.9%) of N-(2-chloro-4-fiuoro-3-nitrobenzoyl)-N'-isopropy!-N'-
methylsulfamide were admixed in 397 g of methanol witli 2.17 g (0.008 mol%) of 1%
Pt/C (63% suspension in water). The mixture was hydrogenated with 5 bar of hydrogen
at 60-70°C with stirring. After 2 h, the solution was decompressed, the reaction mixture
was filtered at SO'C and the solvent was removed by distillation. 157.8 g (97.5% of
theory, purity: 99%) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i-propyl-N'-methylsulf-
amide were obtained as a white-yellowish solid (m.p.: 147-149°C).
1H NMR (400 MHz, d-DMSO) 8 =11.9 ppm (s, NH), 7.35 (d, Ar-H), 6.90 (d, Ar-H), 5.50
(br. s., NH2), 4.05 (sept., Pr-H), 2.80 (s, Me), 1.15 (d, /Pr-H).
Step d1): N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]-N'-i-propyl-N'-methyl-
sulfamide (variant 1)
To a solution of 50.0 g (0.153 mol; 99.3%) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i-
propyl-N'-methylsulfamide in 225 g of toluene were added, at 105-110°C, 22.7 g
(0.207 mol) of ethyl chloroformate and the mixture was subsequently stirred at 108-
110°C for 6.5 h. The reaction mixture was concentrated to dryness on a rotary
evaporator under reduced pressure. After drying under reduced pressure at 70°C,
59.9 g (98.4% of theory, purity 99.7%) of N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)-
amino}benzoyl]-N'-i-propyl-N'-methylsulfamide were obtained.
"¦H NMR (400 MHz, CDCI3) 5 = 8.9 ppm (s, NH), 8.4 (d, Ar-H), 7.2 (d, Ar-H), 6.80 (s,
NH), 4.30-4.20 (m, /Pr-H, CHJD), 2.95 (s. Me), 1.40 (q, C/y3CH20), 1.25 (d, Pr-H).
Step d 1): N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]-N'-i-propyl-N'-methyl-
sulfamide (variant 2)
To a solution of 50.0 g (0.153 mol; 99.3%) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i-
propyl-N'-methylsulfamide in 450 g of toluene were added, at 105-110°C, 26.9 g
(0.245 mol) of ethyl chloroformate and the mixture was then stirred at 108-110°C for
6.5 h. The reaction mixture was concentrated to dryness on a rotary evaporator under
reduced pressure. After drying under reduced pressure at 70'C, 61.2 g (99.3% of
theory, purity 98.4%) of N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]-N'-i-
propyl-N'-methylsulfamide were obtained.
Step d2): 2-chloro-5-[3,6-dihydro-2,6-dioxo-4-(trifluoromethyl)-1 (2H)-pyrimidinyl]-4-
fluoro-N-{[methyl-(1-methylethyl)amino]sulfonyl}benzamide
396 g (1 mol) of N-(2-chloro-4-fluoro-5-[(ethoxycarbonyl)amino]benzoyl)-N'-isopropyl-
N'-methylsulfamide were dissolved at room temperature in 1583 g of DMF, and 189 g

(1.02 mol) of ethyl 3-amino-4,4,4-trifluoro-2-butenoate were added. 378 g (2.1 mol) of
sodium methoxide solution (30% in methanol) were metered in at 115 - 120°C within
4 h, and methanol and ethanol were distilled off during this time. The mixture was left to
stir for a further 30 min. For workup, the reaction mixture was metered with cooling Into
dilute sulfuric acid, and, after the end of the addition, the reaction mixture had a pH of
filtered off, washed with water and dried. 433 g (89% of theory) of the title compound
were obtained [m.p. 238°C (decomposition)].
Stepd3):2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1-(2H)-
pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]benzamlde
40.0 g (0.0785 mol) of 2-chloro-5-[3,6-dihydro-2,6-dioxo-4-(trifluoromethyl)-1 (2H)-
pyrimidinyi]-4-fluoro-N-{[methyl-(1 -methylethyl)amino]sulfonyl}benzamide, 2.5 g
(0.0078 mol) of tetrabutylammonium bromide (= TBAB) and 13.4 g (0.106 mol) of
dimethyl sulfate were initially charged at 25°C In a mixture of toluene, water and THF,
and the mixture was heated to 40°C. Subsequently, by adding aqueous 10% NaOH
solution, a pH of 5.3 - 5.5 was established in the reaction mixture. The mixture was
stirred at 40°C for 1 h, in the course of which 10% aqueous NaOH solution continued to
be added, such that the pH was constant at the pH established beforehand. After 1 h,
the addition of the aqueous 10% NaOH solution was stopped, whereupon the pH fell to
4.4 - 4.5. The mixture was left to stir at a pH of 4.4 - 4.5 and 40°C for a further 5.5 h.
After the reaction had ended, the phases were separated, the organic phase was dried
and the solvent was partly removed. In the course of cooling, the title compound
crystallizes out, and is filtered off, washed with toluene and dried (33 g, 84%).
Example 3: Preparation of 2-chloro-5-[3,6-dihydro-3-methyl-2,6-dloxo-4-(trifluoro-
methyl)-1-(2H)-pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]-
benzamide (variant with performance of steps c) and d1) without intermediate
isolation):
The preparation was effected analogously to the method for example 2, with the
difference that steps c) and d1) were carried out as follows:
179 g (0.500 mol; 99%) of N-(2-chloro-4-fluoro-3-nitrobenzoyl)-N'-isopropyl-N'-methyl-
sulfamide were admixed in 391 g of methanol with 4.08 g (0.015 mol%) of 1% Pt/C
(63% water) and hydrogenated with 5 bar of hydrogen at 60-70°C with stirring. After
2 h, the solution was decompressed, the reaction mixture was filtered at 60°C and the
solution was admixed with 2200 g of toluene. The methanol was removed by distillation
together with the water of reaction at 65-68°C while gradually lowering the pressure
from 900 mbar to 250 mbar. Subsequently, the suspension of N-(2-chloro-4-fluoro-5-
aminobenzoyl)-N'-i-propyl-N'-methylsulfamide in toluene was heated to 106-107°C and

admixed with 64.4 g (0.588 mol) of ethyl chloroformate within 10 min. The mixture was
subsequently stirred at 110°C for 6.5 h. Subsequently, 746 g of toluene were distilled
off at standard pressure and the mixture was then cooled to internal temperature S'C.
After the product solution had been seeded with 150 mg of the target compound, the
product crystallized at 5°C within 60 min. After filtration and drying under reduced
pressure at 70°C, 166.2 g (95.0% of theory, purity 98.5%) of N-[2-chloro-4-fIuoro-5-
{(ethoxycarbonyl)amino}benzoyl]amino}benzoyl]-N'-i-propyl-N'-methylsulfamide were
obtained.
Example 4: Preparation of 2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoro-
methyl)-1-(2H)-pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]-
benzamide (variant with crystallization of the product obtained in d1))
The preparation was effected analogously to the method for example 2, with the
difference that step d1) was carried out as follows:
To a solution of 150.9 g (0.466 mol) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i-
propyl-N'-methylsulfamide in 350 g of methanol and 18.4 g of water were added 1100 g
of toluene. The methanol was removed by distillation together with the water at 65-
68°C while gradually lowering the pressure from 900 mbar to 250 mbar. Subsequently,
the suspension of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N'-i-propyl-N'-methylsulfamide
in toluene was heated to 108-109'C, then admixed with 64.4 g (0.588 mol) of ethyl
chloroformate within 10 min and subsequently stirred at 110°C for 6.5 h. After the
product solution had been seeded with 100 mg of the target compound, the product
crystallized at 5°C within 60 min. After filtration and drying at 70°C under reduced
pressure, 169.6 g (92.0% of theory, purity 99.7%) of N-[2-chloro-4-fluoro-5-
{(ethoxycarbonyl)amino}benzoyl]amino}benzoyl]-N'-i-propyl-N'-methylsulfamidewere
obtained.

Claims:
1. A process for preparing sulfuric diamides of the formula I
R1R2N-S(0)2-NH2 (I)
in which R' and R^ are each independently a primary alkyl radical having from 1
to 8 carbon atoms, a secondary alkyl radical having from 3 to 8 carbon atoms or
a cycloalkyi radical having from 5 to 8 carbon atoms, or, together with the
nitrogen atom, form a 5- to 8-membered, saturated nitrogen heterocycle which,
as well as the nitrogen atom, may have a further heteroatom selected from O and
S as a ring member, where the nitrogen heterocycle may have 1, 2, 3 or 4 alkyl
groups having in each case from 1 to 4 carbon atoms as substituents, comprising
i) the reaction of a secondary amine of the formula II
R1R2NH (II)
in which R^ and R^ are each as defined above with sulfuryl chloride in an
inert organic solvent in the presence of a tertiary amine to give a sulfamoyi
chloride of the formula III
R1R2N-S(0)2-CI (III)
in which R' and R^ are each as defined above, and
ii) reaction of the sulfamoyi chloride of the formula III obtained in step i) with
ammonia,
the sulfamoyi chloride of the formula III being used in step ii) in the form of the
solution obtained in step i) in the inert organic solvent.
2. The process according to claim 1, wherein step i) comprises an extractive
removal of the salts formed in the reaction,
3. The process according to claim 1 or 2, wherein tertiary amine is used in an
amount of from 1.05 to 1.5 equivalents, based on the secondary amine.
4. The process according to any one of the preceding claims, wherein the tertiary
amine is a tri-Ci-Ce-alkylamine.
5. The process according to any one of the preceding claims, wherein the R^ radical
M/48074

in the formuiae I, II and III is a primary alkyl radical having from 1 to 8 carbon
atoms or a secondary alkyl radical having from 3 to 8 carbon atoms and the R^
radicals are each a secondary alkyl radical having from 3 to 8 carbon atoms.
6. The process according to claim 5, wherein the secondary amine of the formula
used is N-(1-methylethyl)-N-methylamine.
7. The process according to any one of the preceding claims, wherein the
secondary amine of the formula II and sulfuryl chloride are used in step i) in a
molar ratio of from 1:1.1 to 1.1:1.
8. The process according to any one of the preceding claims, wherein the inert
organic solvent is an aromatic solvent.
9. The process according to claim 8, wherein the aromatic solvent comprises
chlorobenzene.
10. The process according to any one of the preceding claims, wherein gaseous
ammonia is used in step ii).
11. A process for preparing active herbicidal ingredients of the general formula IV
in which R^ and R2 are each as defined above, R^ is hydrogen or C1-C4-alkyl, R"
is hydrogen, C1-C4-alkyl or CrC4-haloalkyl, X and Y are each hydrogen or
halogen, where one of the X or Y radicals may also be CN, comprising
a) preparation of a sulfuric diamide I by a process according to any one of
claims 1 to 7,
b) reaction of the sulfuric diamide of the formula I with a S-nitrobenzoyI
formula VI;

c) reduction of the 3-nitrobenzenesulfonamide of the formuia VI to a 3-
aminobenzenesulfonamide of the formula VII

d) conversion of the 3-aminobenzenesulfonamide of the formula VII to a
compound of the formula IV,
where the variables R^ R^, X and Y in the formulae V, VI and VII are each as
defined for formula IV.
12. The process according to claim 11, wherein step d) comprises the following
steps:
d1) reaction of the 3-aminobenzenesulfonamide of the formula Vil with a Ct-C4-
alkyl chloroformate to give a compound of the formula VIII

in which R\ R^, X and Y are each as defined for formula IV and R^ is C1-C4-
alkyl,
d2) reaction of the compound VIII with a 3-aminoacrylic ester of the formula IX

in which R3' is hydrogen or C1-C4-alkyl, R' is hydrogen, C1-C4-alkyl or Ci-
C4-haloalkyl and R" is C1-C4-alkyl, and
M/48074
d3) when Ra is hydrogen, optional alkylation of the compound IV obtained in
step d2), in which Ra is hydrogen, with a compound Raa-L in which Raa is
C1-C4-alkyl and L is a nucleophilically displaceable leaving group,
to obtain a compound of the general formula IV.

The present invention relates to a method for producing sulfonic acid amines of the general formula (I) R1R2N-
S(O)2-NH2 (I), where R and R are independent of each other and stand for a primary alkyl radical having 1 to 8 C atoms, a secondary
alkyl radical having 3 to 8 C atoms, or a cycloalkyl radical having 5 to 8 C atoms, or, together with the nitrogen atom, form a 5- to
8-member saturated nitrogen heterocyclic compound that can comprise, in addition to the nitrogen atom, an additional hetero atom,
selected from O and S, as a ring member, wherein the nitrogen heterocyclic compound is unsubstituted, or can comprise 1, 2, 3, or
4 alkyl groups each having 1 to 4 C atoms as substituents. The method comprises the following steps: i) conversion of a secondary
amine of the formula (II) R1R2NH (II), where R and R have the meaning indicated above, having sulfuryl chloride in an inert,
particularly aromatic, solvent in the presence of a tertiary amine, to form a sulfamoyl chloride of the formula (III) R1R2N-S(O)2-CI
(III), where R1 and R2 have the meaning indicated above, and ii) conversion of the sulfamoyl chloride of the formula (III) obtained
in step i) using ammonia, wherein in step ii) the sulfamoyl chloride of the formula (III) is used in the form of the solution obtained
in step i) in the inert, particularly aromatic, solvent.

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Patent Number

277146

Indian Patent Application Number

1232/KOLNP/2010

PG Journal Number

48/2016

Publication Date

18-Nov-2016

Grant Date

11-Nov-2016

Date of Filing

06-Apr-2010

Name of Patentee

BASF SE

Applicant Address

67056 LUDWIGSHAFEN GERMANY

Inventors:

#	Inventor's Name	Inventor's Address
1	KEIL, MICHACL	FONTANESTR 4, 67251 FREINSHEIM GERMANY
2	WEVERS, JAN HENDRIK	GARTENSTR 11, 67591 HOHEN-SULZEN GERMANY
3	LOHR, SANDRA	BENCKISER STR. 30, 67059 LUDWIGSHAFEN GERMANY
4	PLESCHKE, AXEL	GRALSSTRASSE 8, 68199 MANNHEIM GERMANY
5	SCHMIDT, THOMAS	PFARRGASSE 8, 67433 NEUSTADT GERMANY
6	GEBHARDT, JOACHIM	PEGAUER STR. 51, 67157 WACHENHEIM GERMANY

PCT International Classification Number

C07C 303/34

PCT International Application Number

PCT/EP2008/063630

PCT International Filing date

2008-10-10

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	07118416.2	2007-10-12	EPO