Title of Invention	"PROCESS FOR PRODUCING N, N-DIALKYL SUBSTITUTED FATTY ACIDS AMIDES"
Abstract	Disclosed herein is a process for producing dialkyl substituted fatty acid amides. More particularly the present invention provides a process for producing pure form of N,N-dimethylamide of aliphatic carboxylic acids, wherein the aliphatic carboxylic acid is octanoic acid and hexanoic acid. The disclosed process comprises condensing alkanoyl chloride with dilute solution of dialkyl amine at a temperature of about 8 to 12°C and isolating the crude by salting out the reaction mixture employing sodium chloride and distilling the same under vacuum.

Title of Invention

"PROCESS FOR PRODUCING N, N-DIALKYL SUBSTITUTED FATTY ACIDS AMIDES"

Abstract

Disclosed herein is a process for producing dialkyl substituted fatty acid amides. More particularly the present invention provides a process for producing pure form of N,N-dimethylamide of aliphatic carboxylic acids, wherein the aliphatic carboxylic acid is octanoic acid and hexanoic acid. The disclosed process comprises condensing alkanoyl chloride with dilute solution of dialkyl amine at a temperature of about 8 to 12°C and isolating the crude by salting out the reaction mixture employing sodium chloride and distilling the same under vacuum.

Full Text	Field of the Invention In general this invention relates to a process for producing dialkyl substituted fatty acids amides. More particularly, the present invention provides a process for producing pure form of N,N-dialkylamides of aliphatic carboxylic acids. Background of the Invention Dialkyl substituted fatty acids amides are very useful in the commercial-scale production of personal-care formulations, diluents for pesticides and such formulated products. Several processes for producing different short chain, long chain fatty acids or mixed fatty acids amides or substituted fatty acids amides are known in the prior art. These processes differ from each other with respect to the different process chemistry employed, use of the different basic raw materials, and different experimental parameters. British Patent GB 1,521,997 to Kreidl, et al., discloses that carboxylic acids can be converted with very good yields into the appropriate N,N-disubstituted carboxylic amides when an adduct formed from a disubstituted formamide and a chlorinating agent, such as thionyl chloride, is used as the aminating agent. United States Patent No. 3,417,114 to Kuceski, discloses method for producing amides by reacting an ester of a carboxylic acid with an amine, using an alkoxide of an alkali metal as catalyst. United States Patent No. 3,674,851 to Senoo, et al., discloses a process for the preparation of aliphatic tertiary amides which comprises reacting a fatty acid with an alcohol. Additionally a catalyst may be employed to accelerate the rate of reaction. Also disclosed is that all or part of staring materials remaining unreacted and/or by-products may be recycled to the starting reaction mixture, thereby enabling the yield of the desired aliphatic tertiary amides to be remarkably improved. United States Patent No. 3,751,465 to Takahashi, et al., discloses a novel process for the preparation of N,N-dialkyl-substitute fatty amides, which comprises reacting at a temperature in the range of 50 to 1000C under pressure a nitrile with an alcohol, with or without employing a catalyst, and recycling at least a part of the by-products of the reaction to the starting reaction mixture. United States Patent No. 3,856,791 to Daniher, et al., discloses a novel method for producing amides by contacting phosgene with a mixture of an organic compound containing at least one active hydrogen atom and an acid salt of an amine. United States Patent No. 5,254,684 to Izumi, et al, discloses a process for producing an amide which comprises subjecting an oxime to liquid phase rearrangement in the presence of phosphorous pentaoxide and at least one compound selected from the group consisting of N,N-dialkyl amides, N-alkyl cyclic amides and dialkyl sulfoxides and optionally a fluorine-containing strong acid or its derivative. Said process can rearrange an oxime to a corresponding amide in a good yield under mild reaction conditions in the presence of a less stoichiometric amount of a catalyst. United States Patent No. 5,206,225 to Horstmann, et al., discloses the new use of certain alkylcarboxylic acid dimethylamides for prevention of crystallization during the application of aqueous spray liquors based on specific pesticidally active compounds. Ruhoff, et al., (JACS, Vol. 59, p 401, 1937) reported a process for producing dimethyl amides by heating acetic acid saturated with gaseous dimethyl amine at 35°0 for 5 hrs to 200°C in a steel bomb, adding caustic potash to take up water and acetic acid and distilling the purified liquid to obtain dimethyl amides. Also reported is a process for obtaining dimethyl amides in good yields by adding the acid chloride dropwise during 3 hrs to a concentrated aqueous solution of three moles of amine kept at -20 to -10°C, saturating the resulting mixture with KOH in the cold and separating and distilling the dimethyl amide. Org Syn Coll. Vol IV, Page 339, reports a process for producing N,N-Dimethyl cyclohexane carboxamide. Thionyl chloride [179 g] [1.5 m] is added to Cyclohexane carboxyhc acid during 5 minutes. The mixture is refluxed in an oil bath for 2 hrs and cooled to Room Temperature. 200 ml of benzene is charged and the reaction mixture is distilled out till the vapor temperature reaches 95°C. The same operation is repeated with another 200 ml of benzene. In another flask, a solution of 135 g of Dimethyl amine [3.0 m] is charged in 150 ml of anhydrous benzene and cooled in ice bath. The acid chloride is added to the mixture during 2 hrs and the mixture is stirred ovemight. 200 ml of water is added to the mixture and the separated aqueous layer is re-extracted with ether. The combined organic layer is washed with saturated NaCl solution and dried with magnesium sulfate. The organic layer is distilled under vacuum to obtain the pure product 138 g [89%]. Textbook of Practical Organic Chemistry, by Vogel, 5th Edition, Page 708 has reported method of preparation of amides from acid halides. The reaction of acid chloride with an excess of ammonia represents one of the best procedures for the preparation of amides. The use of primary amines or secondary amines in place of ammonia yields corresponding secondary or tertiary amides in reaction with acid chlorides. The method of preparation of Hexanamide is also reported. 125 ml of concentrated ammonia [d-0.88] [25%] [1.96 m] is placed in an ice bath and hexanoyl chloride 56 g [0.42 m] is introduced during 2.0 hrs. The solid is filtered and dried to obtain 30 g of Hexanamide [Yield -63%]. Textbook of Practical Organic Chemistry, by Vogel, 5th Edition, Page 692 has also reported methods of preparation of Hexanoyl chloride. 58 g [0.5 m] of hexanoic acid is heated on a water bath and 72 g [0.6 m] of thionyl chloride is added in 45 mins. The mixture is refluxed for 30 mins and the hexanoyl chloride is isolated by fractional distillation [B.pt.-150-155°C]. Yield - 56 g [83%]. Also reported is the method of preparation of amides from Esters. Amides are easily prepared by the interaction of carboxyhc esters with concentrated aqueous ammonia [ammonolysis]. The reaction proceeds readily in cold, particularly when the methyl esters of lower molecular weight carboxyhc acids are involved, e.g. - Dimethyl succinate to Succinamide. Also reported is the method of preparation of amides from Nitriles. Partial hydrolyses of the nitriles, [for e.g.-Phenyl acetamide from benzyl cyanide] where the nitrile is dissolved in cone HCl at 40°C would yield amides. The present invention discloses an alternative route for producing dialkyl substituted fatty acids amides, which provide considerably simple process step to obtain the pure form of N,N-dialkylamides of aliphatic carboxylic acids wherein the carboxylic acid is hexanoic acid or octanoic acid Summary of the Invention It is the principal aspect of the present invention to provide an industrially feasible and concise process for producing a pure form of N,N-dialkylamides of aliphatic carboxylic acids, the process comprising condensing alkanoyl chloride with dilute solution of dimethyl amine at a temperature of 8 to 12°C and isolating the crude by salting out the resultant. It is also an aspect, of the present invention to provide a process for producing a pure form of N,N-dialkylamides of aliphatic carboxylic acids, wherein the said N,N-dialkylamide is a dimethylamide of hexanoic acid, which is prepared by condensing hexanoyl chloride with dilute solution of dimethyl amine at a temperature of 8 to 12°C and isolating the crude by salting out the resultant. In another aspect of the present invention, there is provided a process for producing a pure form of N,N-dialkylamides of aliphatic carboxylic acids, wherein the said N,N-dialkylamide is a dimethylamide of octanoic acid, which is prepared by condensing octanoyl chloride with the dilute solution of dimethyl amine at a temperature of 8 to 12°C and isolating the crude by salting out the resultant. In still another aspect of the present invention, there is provided a simple isolation process for obtaining a pure form of N, N-dialkylamides of aliphatic carboxylic acids, wherein the process comprises adding sodium chloride in the reaction mixture which is prepared by condensing alkanoyl chloride with dilute solution of dimethyl amine and salting out the reaction mixture to get the pure product. In still another aspect of the present invention, there is provided a process for producing pure form of N,N-dialkylamide of aliphatic carboxylic acids, wherein the process is carried out in liquid medium. In a preferred embodiment there is provided a process for producing a pure form of dimethylamide of octanoic acid wherein the process comprising, charging diluted aqueous solution of dimethyl amine in a reaction pot at room temperature and cooling the same till 10°C, adding the octanoyl chloride at a temperature of about 8-12°C, stirring the reaction mixture for about 30 minutes and allowing the reaction mixture to attain room temperature and further stirring for about 1 hour, separating the lower aqueous layer and upper organic layer, adding the sodium chloride to organic layer and salting out the crude and distilling the same under vacuum to get pure dimethylamide of octanoic acid. In another preferred embodiment there is provided a process for producing a pure form of dimethylamide of hexanoic acid wherein the process comprises, charging diluted aqueous solution of dimethyl amine in a reaction pot at room temperature and cooling the same till 10°C, adding the hexanoyl chloride at a temperature of about 8-12°C, stirring the reaction mixture for about 30 minutes and allowing the reaction mixture to attain room temperature and further stirring for about 1 hour, adding the sodium chloride to the reaction mixture and salting out the crude and distilling the same imder vacuum to get pure dimethylamide of hexanoic acid. Detailed Description of the Invention The present invention relates to a novel and industrially applicable process for producing highly pure form of N, N-dialkylamides of aliphatic carboxylic acids, which has an advantage from prior art processes in providing a considerable simplification of the process as well as avoiding high temperature and pressure. According to present invention, the reaction between acid chloride and diluted solution of dimethylamine is carried out at a temperature of about 8-12°C and thus avoids very low temperature as well as very high temperature, as very low temperature would slow down the reaction rate and high temperature would promote side reactions and the formation of by-products. According to the present invention, the process providing simple isolation of N,N-dialkylamide of aliphatic carboxylic acids by employing sodium chloride and salting out to get the crude product, instead of using potassium hydroxide in cold condition to remove the acid and water as mentioned in the prior art. Thus avoiding the additional process step and the process is made more simplified. This invention is explained below in more detail, referring to Examples, which are described by way of illustration and not by way of limitation: Example 1 Preparation of Hexanovl Chloride: 116.2 g of Hexanoic acid is charged at room temperature and heated to 40°C, then 142.7 g of thionyl chloride is added over a period of 1 hour and the reaction mixture is heated to reflux at 90°C for V1/2 hour to obtain crude hexanoyl chloride. Example 2 Preparation of Crude Hexanamide: 135.03 g of dimethyl amine solution is charged at room temperature and cooled to 10°C, then hexanoyl chloride obtained in Example 1 is charged at 8 to 12°C over a period of 2 hours, and the reaction mixture is stirred at 10 to 15°C for 30 minutes and then stirred at room temperature for 1 hour. To this saturated reaction mixture is added 29.80 g of sodium chloride, then upper organic layer is separated from lower aqueous layer and 0.994 g of sodium sulphate is added to the organic layer to take up water, and the mixture is filtered to obtain crude Hexanamide. Example 3 Purification of Hexanamide: Crude Hexanamide obtained in Example 2 is distilled under vacuum to obtain pure product (78.31% yield), with GC Purity of 99.15%. Example 4 Preparation of Octanoyl Chloride: 144.2 g of Octanoic acid is charged at room temperature and heated to 40°C, then 154.64 g of thionyl chloride is added over a period of 1 hour and the reaction mixture is heated to reflux at 1 10°C for V1/2 hour to obtain crude octanoyl chloride. Example 5 Preparation of Crude Octanamide: 135.03 of dimethyl amine solution is charged at room temperature and cooled to 10°C, then octanoyl chloride obtained in Example 4 is charged at 8 to 12°C over a period of 2 hours, and the reaction mixture is stirred at 10 to 15°C for 30 minutes and then stirred at room temperature for 1 hour and the upper organic layer is separated from lower aqueous layer and 29.80 g of sodium chloride (20% solution) is added to the organic layer. This organic layer is washed and 9.94 g of sodium sulphate is added to the organic layer to take up water, and the mixture is filtered to obtain crude Octanamide. Example 6 Purification of Octanamide: Crude Hexanamide obtained in Example 5 is distilled under vacuum to obtain pure product (82.91% yield), with GC Purity of 99.57%. Certain modifications and improvements of the disclosed invention will occur to those skilled in the art without departing from the scope of invention, which is limited only by the appended claims. We Claim: 1. A process for producing dialkyl substituted fatty acid amides, the process comprising condensing alkanoyl chloride with dilute aqueous solution of dialkyl amine at a temperature of 8 to 12^C and isolating the crude by salting out the reaction mixture employing sodium chloride and distilling the same under vacuum. 2. The process according to claim 1, wherein the dialkyl substituted fatty acid amide is N,N-dialkylamide of aliphatic carboxylic acids, 3. The process according to claim 2, wherein the N,N-dialkylamide of aliphatic carboxylic acid is N,N-dimethylamide of hexanoic acid. 4. The process according to claim 2, wherein the N,N-dialkylamide of aliphatic carboxylic acid is N,N-dimethylamide of octanoic acid. 5. The process according to claim 1, wherein the alkanoyl chloride is hexanoyl chloride. 6. The process according to claim 1, wherein the alkanoyl chloride is octanoyl chloride. 7. The process according to claim 1, wherein the dialkyl amine is dimethyl amine. 8. The process according to claim 1, wherein the process is carried out in a liquid medium. 9. A process for producing dialkyl substituted fatty acid amides, the process comprising charging dilute aqueous solution of dialkyl amine in a reaction pot at room temperature and cooling the same till 10°C, adding the alkanoyl chloride at a temperature of 8-12°C, stirring the reaction mixture for about 30 minutes, allowing the reaction mixture to attain room temperature, further stirring for about 1 hour, separating the organic layer from the aqueous layer, adding the sodium chloride to organic layer, salting out the crude and distilling the same under vacuum to get pure dialkyl substituted fatty acids. 10. The process according to claim 9, wherein the dialkyl substituted fatty acid amide is N,N-dialkylamide of aliphatic carboxylic acids. 11. The process according to claim 10, wherein the N,N-dialkylamide of aliphatic carboxylic acid is N,N-dimethylamide of octanoic acid. 12. The process according to claim 9, wherein the alkanoyl chloride is octanoyl chloride. 13. The process according to claim 9, wherein the dialkyl amine is dimethyl amine. 14. A process for producing dialkyl substituted fatty acid amides, the process comprising charging dilute aqueous solution of dialkyl amine in a reaction pot at room temperature, cooling the same till lO^C, adding the alkanoyl chloride at a temperature of 8-12^C, stirring the reaction mixture for about 30 minutes, allowing the reaction mixture to attain room temperature, further stirring for about 1 hour, adding the sodium chloride to the reaction mixture, salting out the crude and distilling the same under vacuum to get pure dialkyl substituted fatty acids. 15. The process according to claim 14, wherein the dialkyl substituted fatty acid amide is N,N-dialkylamide of aliphatic carboxylic acids. 16. The process according to claim 15, wherein the N,N-dialkylamide of aliphatic carboxylic acid is N,N-dimethylamide of hexanoic acid. 17. The process according to claim 14, wherein the alkanoyl chloride is hexanoyl chloride. 18. The process according to claim 14, wherein the dialkyl amine is dimethyl amine. 19. A process for producing dialkyl substituted fatty acid amides substantially as hereinbefore described with reference to the examples.

Full Text

Field of the Invention
In general this invention relates to a process for producing dialkyl substituted fatty acids amides. More particularly, the present invention provides a process for producing pure form of N,N-dialkylamides of aliphatic carboxylic acids.
Background of the Invention
Dialkyl substituted fatty acids amides are very useful in the commercial-scale production of personal-care formulations, diluents for pesticides and such formulated products.
Several processes for producing different short chain, long chain fatty acids or mixed fatty acids amides or substituted fatty acids amides are known in the prior art. These processes differ from each other with respect to the different process chemistry employed, use of the different basic raw materials, and different experimental parameters.
British Patent GB 1,521,997 to Kreidl, et al., discloses that carboxylic acids can be converted with very good yields into the appropriate N,N-disubstituted carboxylic amides when an adduct formed from a disubstituted formamide and a chlorinating agent, such as thionyl chloride, is used as the aminating agent.
United States Patent No. 3,417,114 to Kuceski, discloses method for producing amides by reacting an ester of a carboxylic acid with an amine, using an alkoxide of an alkali metal as catalyst.
United States Patent No. 3,674,851 to Senoo, et al., discloses a process for the preparation of aliphatic tertiary amides which comprises reacting a fatty acid with an alcohol. Additionally a catalyst may be employed to accelerate the rate of reaction. Also disclosed is that all or part of staring materials remaining unreacted and/or by-products may be recycled to the starting reaction mixture, thereby enabling the yield of the desired aliphatic tertiary amides to be remarkably improved.

United States Patent No. 3,751,465 to Takahashi, et al., discloses a novel process for the preparation of N,N-dialkyl-substitute fatty amides, which comprises reacting at a temperature in the range of 50 to 1000C under pressure a nitrile with an alcohol, with or without employing a catalyst, and recycling at least a part of the by-products of the reaction to the starting reaction mixture.
United States Patent No. 3,856,791 to Daniher, et al., discloses a novel method for producing amides by contacting phosgene with a mixture of an organic compound containing at least one active hydrogen atom and an acid salt of an amine.
United States Patent No. 5,254,684 to Izumi, et al, discloses a process for producing an amide which comprises subjecting an oxime to liquid phase rearrangement in the presence of phosphorous pentaoxide and at least one compound selected from the group consisting of N,N-dialkyl amides, N-alkyl cyclic amides and dialkyl sulfoxides and optionally a fluorine-containing strong acid or its derivative. Said process can rearrange an oxime to a corresponding amide in a good yield under mild reaction conditions in the presence of a less stoichiometric amount of a catalyst.
United States Patent No. 5,206,225 to Horstmann, et al., discloses the new use of certain alkylcarboxylic acid dimethylamides for prevention of crystallization during the application of aqueous spray liquors based on specific pesticidally active compounds.
Ruhoff, et al., (JACS, Vol. 59, p 401, 1937) reported a process for producing dimethyl amides by heating acetic acid saturated with gaseous dimethyl amine at 35°0 for 5 hrs to 200°C in a steel bomb, adding caustic potash to take up water and acetic acid and distilling the purified liquid to obtain dimethyl amides. Also reported is a process for obtaining dimethyl amides in good yields by adding the acid chloride dropwise during 3 hrs to a concentrated aqueous solution of three moles of amine kept at -20 to -10°C, saturating the resulting mixture with KOH in the cold and separating and distilling the dimethyl amide.
Org Syn Coll. Vol IV, Page 339, reports a process for producing N,N-Dimethyl cyclohexane carboxamide. Thionyl chloride [179 g] [1.5 m] is added to Cyclohexane

carboxyhc acid during 5 minutes. The mixture is refluxed in an oil bath for 2 hrs and cooled to Room Temperature. 200 ml of benzene is charged and the reaction mixture is distilled out till the vapor temperature reaches 95°C. The same operation is repeated with another 200 ml of benzene. In another flask, a solution of 135 g of Dimethyl amine [3.0 m] is charged in 150 ml of anhydrous benzene and cooled in ice bath. The acid chloride is added to the mixture during 2 hrs and the mixture is stirred ovemight. 200 ml of water is added to the mixture and the separated aqueous layer is re-extracted with ether. The combined organic layer is washed with saturated NaCl solution and dried with magnesium sulfate. The organic layer is distilled under vacuum to obtain the pure product 138 g [89%].
Textbook of Practical Organic Chemistry, by Vogel, 5th Edition, Page 708 has reported method of preparation of amides from acid halides. The reaction of acid chloride with an excess of ammonia represents one of the best procedures for the preparation of amides. The use of primary amines or secondary amines in place of ammonia yields corresponding secondary or tertiary amides in reaction with acid chlorides. The method of preparation of Hexanamide is also reported. 125 ml of concentrated ammonia [d-0.88] [25%] [1.96 m] is placed in an ice bath and hexanoyl chloride 56 g [0.42 m] is introduced during 2.0 hrs. The solid is filtered and dried to obtain 30 g of Hexanamide [Yield -63%].
Textbook of Practical Organic Chemistry, by Vogel, 5th Edition, Page 692 has also reported methods of preparation of Hexanoyl chloride. 58 g [0.5 m] of hexanoic acid is heated on a water bath and 72 g [0.6 m] of thionyl chloride is added in 45 mins. The mixture is refluxed for 30 mins and the hexanoyl chloride is isolated by fractional distillation [B.pt.-150-155°C]. Yield - 56 g [83%].
Also reported is the method of preparation of amides from Esters. Amides are easily prepared by the interaction of carboxyhc esters with concentrated aqueous ammonia [ammonolysis]. The reaction proceeds readily in cold, particularly when the methyl esters of lower molecular weight carboxyhc acids are involved, e.g. - Dimethyl succinate to Succinamide.

Also reported is the method of preparation of amides from Nitriles. Partial hydrolyses of the nitriles, [for e.g.-Phenyl acetamide from benzyl cyanide] where the nitrile is dissolved in cone HCl at 40°C would yield amides.
The present invention discloses an alternative route for producing dialkyl substituted fatty acids amides, which provide considerably simple process step to obtain the pure form of N,N-dialkylamides of aliphatic carboxylic acids wherein the carboxylic acid is hexanoic acid or octanoic acid
Summary of the Invention
It is the principal aspect of the present invention to provide an industrially feasible and concise process for producing a pure form of N,N-dialkylamides of aliphatic carboxylic acids, the process comprising condensing alkanoyl chloride with dilute solution of dimethyl amine at a temperature of 8 to 12°C and isolating the crude by salting out the resultant.
It is also an aspect, of the present invention to provide a process for producing a pure form of N,N-dialkylamides of aliphatic carboxylic acids, wherein the said N,N-dialkylamide is a dimethylamide of hexanoic acid, which is prepared by condensing hexanoyl chloride with dilute solution of dimethyl amine at a temperature of 8 to 12°C and isolating the crude by salting out the resultant.
In another aspect of the present invention, there is provided a process for producing a pure form of N,N-dialkylamides of aliphatic carboxylic acids, wherein the said N,N-dialkylamide is a dimethylamide of octanoic acid, which is prepared by condensing octanoyl chloride with the dilute solution of dimethyl amine at a temperature of 8 to 12°C and isolating the crude by salting out the resultant.
In still another aspect of the present invention, there is provided a simple isolation process for obtaining a pure form of N, N-dialkylamides of aliphatic carboxylic acids, wherein the process comprises adding sodium chloride in the reaction mixture which is prepared by

condensing alkanoyl chloride with dilute solution of dimethyl amine and salting out the reaction mixture to get the pure product.
In still another aspect of the present invention, there is provided a process for producing pure form of N,N-dialkylamide of aliphatic carboxylic acids, wherein the process is carried out in liquid medium.
In a preferred embodiment there is provided a process for producing a pure form of dimethylamide of octanoic acid wherein the process comprising, charging diluted aqueous solution of dimethyl amine in a reaction pot at room temperature and cooling the same till 10°C, adding the octanoyl chloride at a temperature of about 8-12°C, stirring the reaction mixture for about 30 minutes and allowing the reaction mixture to attain room temperature and further stirring for about 1 hour, separating the lower aqueous layer and upper organic layer, adding the sodium chloride to organic layer and salting out the crude and distilling the same under vacuum to get pure dimethylamide of octanoic acid.
In another preferred embodiment there is provided a process for producing a pure form of dimethylamide of hexanoic acid wherein the process comprises, charging diluted aqueous solution of dimethyl amine in a reaction pot at room temperature and cooling the same till 10°C, adding the hexanoyl chloride at a temperature of about 8-12°C, stirring the reaction mixture for about 30 minutes and allowing the reaction mixture to attain room temperature and further stirring for about 1 hour, adding the sodium chloride to the reaction mixture and salting out the crude and distilling the same imder vacuum to get pure dimethylamide of hexanoic acid.
Detailed Description of the Invention
The present invention relates to a novel and industrially applicable process for producing highly pure form of N, N-dialkylamides of aliphatic carboxylic acids, which has an advantage from prior art processes in providing a considerable simplification of the process as well as avoiding high temperature and pressure.

According to present invention, the reaction between acid chloride and diluted solution of dimethylamine is carried out at a temperature of about 8-12°C and thus avoids very low temperature as well as very high temperature, as very low temperature would slow down the reaction rate and high temperature would promote side reactions and the formation of by-products.
According to the present invention, the process providing simple isolation of N,N-dialkylamide of aliphatic carboxylic acids by employing sodium chloride and salting out to get the crude product, instead of using potassium hydroxide in cold condition to remove the acid and water as mentioned in the prior art. Thus avoiding the additional process step and the process is made more simplified.
This invention is explained below in more detail, referring to Examples, which are described by way of illustration and not by way of limitation:
Example 1 Preparation of Hexanovl Chloride:
116.2 g of Hexanoic acid is charged at room temperature and heated to 40°C, then 142.7 g
of thionyl chloride is added over a period of 1 hour and the reaction mixture is heated to
reflux at 90°C for V1/2 hour to obtain crude hexanoyl chloride.
Example 2 Preparation of Crude Hexanamide:
135.03 g of dimethyl amine solution is charged at room temperature and cooled to 10°C,
then hexanoyl chloride obtained in Example 1 is charged at 8 to 12°C over a period of 2
hours, and the reaction mixture is stirred at 10 to 15°C for 30 minutes and then stirred at
room temperature for 1 hour. To this saturated reaction mixture is added 29.80 g of
sodium chloride, then upper organic layer is separated from lower aqueous layer and
0.994 g of sodium sulphate is added to the organic layer to take up water, and the mixture
is filtered to obtain crude Hexanamide.

Example 3 Purification of Hexanamide:
Crude Hexanamide obtained in Example 2 is distilled under vacuum to obtain pure product (78.31% yield), with GC Purity of 99.15%.
Example 4 Preparation of Octanoyl Chloride:
144.2 g of Octanoic acid is charged at room temperature and heated to 40°C, then 154.64
g of thionyl chloride is added over a period of 1 hour and the reaction mixture is heated to
reflux at 1 10°C for V1/2 hour to obtain crude octanoyl chloride.
Example 5 Preparation of Crude Octanamide:
135.03 of dimethyl amine solution is charged at room temperature and cooled to 10°C,
then octanoyl chloride obtained in Example 4 is charged at 8 to 12°C over a period of 2
hours, and the reaction mixture is stirred at 10 to 15°C for 30 minutes and then stirred at
room temperature for 1 hour and the upper organic layer is separated from lower aqueous
layer and 29.80 g of sodium chloride (20% solution) is added to the organic layer. This
organic layer is washed and 9.94 g of sodium sulphate is added to the organic layer to
take up water, and the mixture is filtered to obtain crude Octanamide.
Example 6 Purification of Octanamide:
Crude Hexanamide obtained in Example 5 is distilled under vacuum to obtain pure product (82.91% yield), with GC Purity of 99.57%.
Certain modifications and improvements of the disclosed invention will occur to those skilled in the art without departing from the scope of invention, which is limited only by the appended claims.

We Claim:
1. A process for producing dialkyl substituted fatty acid amides, the process comprising condensing alkanoyl chloride with dilute aqueous solution of dialkyl amine at a temperature of 8 to 12^C and isolating the crude by salting out the reaction mixture employing sodium chloride and distilling the same under vacuum.
2. The process according to claim 1, wherein the dialkyl substituted fatty acid amide is N,N-dialkylamide of aliphatic carboxylic acids,
3. The process according to claim 2, wherein the N,N-dialkylamide of aliphatic carboxylic acid is N,N-dimethylamide of hexanoic acid.
4. The process according to claim 2, wherein the N,N-dialkylamide of aliphatic carboxylic acid is N,N-dimethylamide of octanoic acid.
5. The process according to claim 1, wherein the alkanoyl chloride is hexanoyl chloride.
6. The process according to claim 1, wherein the alkanoyl chloride is octanoyl chloride.
7. The process according to claim 1, wherein the dialkyl amine is dimethyl amine.
8. The process according to claim 1, wherein the process is carried out in a liquid medium.
9. A process for producing dialkyl substituted fatty acid amides, the process comprising charging dilute aqueous solution of dialkyl amine in a reaction pot at room temperature and cooling the same till 10°C, adding the alkanoyl chloride at a temperature of 8-12°C, stirring the reaction mixture for about 30 minutes, allowing the reaction mixture to attain room temperature, further stirring for about 1 hour, separating the organic layer from the aqueous layer, adding the sodium chloride to organic layer, salting out the crude and distilling the same under vacuum to get pure dialkyl substituted fatty acids.
10. The process according to claim 9, wherein the dialkyl substituted fatty acid amide is N,N-dialkylamide of aliphatic carboxylic acids.
11. The process according to claim 10, wherein the N,N-dialkylamide of aliphatic carboxylic acid is N,N-dimethylamide of octanoic acid.

12. The process according to claim 9, wherein the alkanoyl chloride is
octanoyl chloride.
13. The process according to claim 9, wherein the dialkyl amine is dimethyl
amine.
14. A process for producing dialkyl substituted fatty acid amides, the process
comprising charging dilute aqueous solution of dialkyl amine in a reaction pot at room
temperature, cooling the same till lO^C, adding the alkanoyl chloride at a temperature of
8-12^C, stirring the reaction mixture for about 30 minutes, allowing the reaction mixture
to attain room temperature, further stirring for about 1 hour, adding the sodium chloride
to the reaction mixture, salting out the crude and distilling the same under vacuum to get
pure dialkyl substituted fatty acids.
15. The process according to claim 14, wherein the dialkyl substituted fatty acid amide is N,N-dialkylamide of aliphatic carboxylic acids.
16. The process according to claim 15, wherein the N,N-dialkylamide of aliphatic carboxylic acid is N,N-dimethylamide of hexanoic acid.
17. The process according to claim 14, wherein the alkanoyl chloride is
hexanoyl chloride.
18. The process according to claim 14, wherein the dialkyl amine is dimethyl
amine.
19. A process for producing dialkyl substituted fatty acid amides substantially
as hereinbefore described with reference to the examples.

Documents:

967-CHE-2004 AMENDED CLAIMS 07-02-2013.pdf

967-CHE-2004 AMENDED CLAIMS 18-09-2013.pdf

967-CHE-2004 AMENDED PAGES OF SPECIFICATION 07-02-2013.pdf

967-CHE-2004 AMENDED PAGES OF SPECIFICATION 18-09-2013.pdf

967-CHE-2004 ASSIGNMENT 18-09-2013.pdf

967-CHE-2004 EXAMINATION REPORT REPLY RECEIVED 07-02-2013.pdf

967-CHE-2004 EXAMINATION REPORT REPLY RECEIVED 18-09-2013.pdf

967-CHE-2004 FORM-1 07-02-2013.pdf

967-CHE-2004 FORM-13 07-02-2013.pdf

967-CHE-2004 FORM-3 18-09-2013.pdf

967-CHE-2004 FORM-5 07-02-2013.pdf

967-CHE-2004 OTHER PATENT DOCUMENT 07-02-2013.pdf

967-CHE-2004 OTHER PATENT DOCUMENT 18-09-2013.pdf

967-CHE-2004 POWER OF ATTORNEY 07-02-2013.pdf

967-CHE-2004 POWER OF ATTORNEY 12-02-2013.pdf

967-CHE-2004 AMENDED PAGES OF SPECIFICATION 17-01-2014.pdf

967-CHE-2004 CORRESPONDENCE OTHERS 07-03-2013.pdf

967-CHE-2004 CORRESPONDENCE OTHERS 12-02-2013.pdf

967-CHE-2004 FORM-3 07-03-2013.pdf

967-CHE-2004 OTHER PATENT DOCUMENT 07-03-2013.pdf

967-CHE-2004 OTHERS 07-03-2013.pdf

967-CHE-2004 EXAMINATION REPORT REPLY RECEIVED 17-01-2014.pdf

967-che-2004-abstract.pdf

967-che-2004-claims.pdf

967-che-2004-correspondnece-others.pdf

967-che-2004-description(complete).pdf

967-che-2004-form 1.pdf

967-che-2004-form 3.pdf

« Previous Patent

Next Patent »

Patent Number

258564

Indian Patent Application Number

967/CHE/2004

PG Journal Number

04/2014

Publication Date

24-Jan-2014

Grant Date

21-Jan-2014

Date of Filing

23-Sep-2004

Name of Patentee

RAMACHANDRAN RADHAKRISHNAN

Applicant Address

B1/1202, L&T "SOUTH CITY" APARTMENT, BANNERGHATA ROAD, BANGALORE-560 076, INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	RADHAKRISHNAN, RAMACHANDRAN	B1/1202, L&T "SOUTH CITY" APARTMENT, BANNERGHATA ROAD, BANGALORE-560 076, INDIA.
2	ADHIKARI, SISIR, K	C-25, FLAT NO. 6, LIC COLONY, BORIVALI (W), MUMBAI, INDIA.

PCT International Classification Number

C07C 233/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA