Title of Invention	METHOD OF PRODUCING SILYLALKOXYMETHYL HALIDE.
Abstract	A method for making a silylalkoxymethyl halide at good yield represented by the formula: R1R2 R3Si-R4-O-CH2X wherein R1 , R2 , and R3 are an alkyl, cycloalkyl, aryl group, or a halogen atom, R4 is a divalent hydrocarbyl group having 1 to 10 carbon atoms, and X is a halogen atom, by reacting: (a) a silyl alcohol compound with the formula R1R2 R3Si-R4 -OH wherein R1 , R2 , R3 and R4 arc defined as above, with (b) formaldehyde or a polymer thereof, and (c) a halosilane.

Title of Invention

METHOD OF PRODUCING SILYLALKOXYMETHYL HALIDE.

Abstract

A method for making a silylalkoxymethyl halide at good yield represented by the formula: R1R2 R3Si-R4-O-CH2X wherein R1 , R2 , and R3 are an alkyl, cycloalkyl, aryl group, or a halogen atom, R4 is a divalent hydrocarbyl group having 1 to 10 carbon atoms, and X is a halogen atom, by reacting: (a) a silyl alcohol compound with the formula R1R2 R3Si-R4 -OH wherein R1 , R2 , R3 and R4 arc defined as above, with (b) formaldehyde or a polymer thereof, and (c) a halosilane.

Full Text	DESCRIPTION Field of the Invention [0001] This invention relates to a novel method of manufacturing a silylalkoxymethyl halide, the product being obtained easily and with a high yield. Background of the Invention [0002] Silylalkoxymethyl halides are publicly known. Among these compounds, trimethylsilylmethoxymethyl chloride and phenyldimethylsilylmethoxymethyl chloride in particular are very important in the synthesis of bio-active substances and natural products with complex structures as reagents that protect functional groups containing active hydrogen. [0003] Some examples of synthesis by several methods have already been reported for silylalkoxymethyl chlorides such as trimethylsilylmethoxymethyl chloride and phenyldimethylsilylmethoxymethyl chloride (See to Bruce H. Lipshutz et al., Tetrahedron Letters (Great Britain), Volume 21 (1980), pp. 3343-3346; Denis Guedin-Vunong et al., Bulletin de la Societe Chimique de France (France), No. 2 (1986), pp. 245-252; Arthur G. Schultz et al., Organic Preparations and Procedures International (US), Volume 27 (1995), pp. 572-574; and G. J. P. H. Boons et al., Tetrahedron Letters (Great Britain), Volume 31 (1990), pp. 2197-2200). These synthesis examples involve chloromethylation of the corresponding silyl alcohol using hydrogen chloride gas in the presence of a formaldehyde polymer. [0004] However, there is a substantial problem to execute this procedure on an industrial basis. Specifically, the generation of by-product water cannot be avoided during chloromethylation using hydrogen chloride gas, and this water reacts with the product, resulting in product decomposition. The result is either a major reduction in the yield of the target silylalkoxymethyl chloride or a complete failure to obtain the target silylalkoxymethyl chloride. [0005] In the aforementioned references, the by-product water is removed from the system by introducing a dehydrating agent, such as magnesium sulfate, immediately after the reaction. However, the implementation of this procedure on an industrial basis is cumbersome and complicated, and the product decomposition also proceeds during the time required to carry out the dehydration treatment. Moreover, the dehydrating agent must be separated from the product by, for example, filtration, which lengthens the process time, increases the amount of waste, raises the production costs, and lowers the yield. [0006] In addition to the preceding, hydrogen chloride gas is a gaseous reagent and thus is much more difficult to handle than ordinary liquid reagents. It is difficult, in particular, to measure the amount used in the reaction, making it necessary to use a large excess of the gas and thereby raising the costs and increasing the amount of waste. [0007] A. G. Shipov et al., Zhurnal Obshchei Khimii (formerly the USSR), Volume 59 (1989), pp. 1204-1205, describes a method for manufacturing alkoxymethyl chloride by the reaction of an aryl alcohol or alkyl alcohol with formula (3) R-OH (3) wherein R is phenylmethyl or an alkyl group having 1, 5, 8, 10 or 12 carbon atoms, with paraformaldehyde in chlorotrimethylsilane. However, this reference does neither describe nor suggest the use of a silyl alcohol as a starting material. Summary of the Invention [0009] This invention solves the problems noted above, and its object is the introduction of a high yield method of manufacturing silylalkoxymethyl halide. The method does not require the use of difficult-to-handle hydrogen chloride gas, it does not generate by-product water, it does not require a dehydrating agent, it generates little solid waste, and it requires less time for manufacturing silylalkoxymethyl halide than current methods. [0010] As a result, in accordance with the invention, it has been discovered that a silylalkoxymethyl halide represented by formula (1): wherein R1, R2, and R3 are alkyl, cycloalkyl, aryl group, or a halogen atom, R4 is divalent hydrocarbyl group having 1 to 10 carbon atoms, and X is a halogen atom, could be synthesized at good efficiencies by reacting (a) a silyl alcohol compound represented by formula (2): wherein R1, R2, and R3 are alkyl, cycloalkyl, aryl, or a halogen atom, and R4 is divalent hydrocarbyl group having 1 to 10 carbon atoms, with (b) formaldehyde or a polymer thereof, and (c) a halosilane. It was also discovered that high purity silylalkoxymethyl halide could be obtained in high yields by distilling out, under the application of reduced pressure, hydrogen halide generated as a by-product in the reaction, excess halosilane, and the reaction product of water and halosilane; and thereafter adding (d) a tertiary amine, and distilling the silylalkoxymethyl halide. [0011] The method of the invention enables a high yield and industrially facile and efficient synthesis of a silylalkoxymethyl halide represented by formula (1): wherein R1, R2, and R3 are alkyl, cycloalkyl, aryl, or a halogen atom, R4 is divalent hydrocarbyl group having 1 to 10 carbon atoms, and X is a halogen atom, without using either hydrogen chloride gas or a dehydrating agent, and it does so while making it possible to reduce the amount of solid waste. Detailed Description of the Invention [0012] According to the method, the (a) silyl alcohol compound represented by formula (2): is the primary starting material. R1, R2, and R3 in formula (2) are alkyl, cycloalkyl, aryl, or a halogen atom, while R4 is a divalent hydrocarbyl group having 1 to 10 carbon atoms. R1, R2, and R3 can be specifically exemplified by alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, isopentyl, hexyl, and isohexyl; cycloalkyl groups such as cyclopentyl, cyclohexyl, and cycloheptyl; aryl groups such as phenyl, tolyl, xylyl, and naphthyl; and halogen atoms such as the chlorine atom and fluorine atom. R4 is specifically exemplified by methylene; alkylene having 2 to 10 carbon atoms such as ethylene, propylene, and butylene; cycloalkylene having 3 to 10 carbon atoms such as cyclopentylene and cyclohexylene; and arylene having 6 to 10 carbon atoms such as phenylene and naphthylene. When the compound represented by formula (1) prepared in accordance with the invention is used as a reagent for protecting active hydrogen-containing functional groups, R', R2, and R3 are preferably methyl, ethyl, propyl, isopropyl, or phenyl, and R4 preferably is methylene, ethylene, or propylene, and more preferably ethylene. The silyl alcohol compound represented by formula (2) can be specifically exemplified by trimethylsilylmethanol, 2- trimethylsilylethanol, 3-trimethylsilylpropanol, 2-triethylsilylethanol, 2- triisopropylsilylethanol, and 2-dimethylphenylsiIylethanol. These silyl alcohol compounds can in some cases be acquired as reagents, and when necessary can also be synthesized by known procedures. [0013] The (b) formaldehyde or polymer thereof is a generally known formaldehyde equivalent. Usable here are, inter alia, gaseous formaldehyde, trioxane (the trimer), and paraformaldehyde (a polymer). Granular paraformaldehyde is particularly preferred from the standpoints of reactivity and ease of handling. Aqueous formalin solutions are undesirable due to the negative effects exercised by their water fraction. The formaldehyde or polymer thereof may be used in a small excess, and preferably in the range of 1 to 1.5 equivalents, with respect to the (a) silyl alcohol compound with formula (2). [0014] The (c) halosilane functions to react with the silyl alcohol compound and thereby produces the hydrogen halide required by the halomethylation reaction, and at the same time functions to scavenge the water generated as a by-product. When the compound represented by formula (1) prepared in accordance with the invention is used as a reagent for protecting active hydrogen-containing functional groups, the halosilane is preferably a chlorosilane or a bromosilane, and more preferably is a chlorosilane. Specific examples are tetrachlorosilane, methyltrichlorosilane, chlorotrimethylsilane, and chlorotriethylsilane. Chlorotrimethylsilane is most preferred when one considers its ease of acquisition and ease of separation of the product after water scavenging. The (c) halosilane is desirably used in excess relative to the (a) silyl alcohol compound represented by formula (2), wherein 2 to 20 equivalents is preferred, and 3 to 5 equivalents is more preferred, in each case referred to the (a) silyl alcohol compound represented by formula (2). [0015] The reaction among the (a) silyl alcohol compound represented by formula (2), (b) formaldehyde or polymer thereof, and the (c) halosilane proceeds readily merely upon mixing the individual components. However, a procedure in which one component is added dropwise to a mixture of the other components is desirable, in order to avoid an overly vigorous reaction. More preferably, the reaction is appropriately carried out by adding the (a) silyl alcohol compound represented by formula (2) dropwise to a mixture of (b) formaldehyde or polymer thereof, and the (c) halosilane. The reaction temperature is preferably low, in order to avoid product decomposition and the range of 0 to 10°C is most preferred. The reaction does not require solvent, but a solvent inert with respect to the individual components such as toluene, xylene, and heptane can be used when necessary. [0016] The target material is obtained after the reaction by distilling out, under the application of reduced pressure, the hydrogen halide, excess halosilane, and water/halosilane reaction product. Purification by distillation is desirably carried out in order to provide an additional increase in target material purity. Improvements in the silylalkoxymethyl halide purity and reaction yield can be obtained by the addition of (d) tertiary amine to this distillative purification, in order to neutralize the hydrogen halide not completely distilled out under reduced pressure, and thereby more effectively inhibit product decomposition. This tertiary amine is preferably triethanolamine or diisopropylethylamine, and is more preferably diisopropylethylamine. [0017] Silylalkoxymethyl halide represented by formula (1) prepared by the method in accordance with the invention can be exemplified by (trimethylsilyl)methoxyethyl chloride, 2-(trimethylsilyl)ethoxymethyl chloride, 3-(trimethylsilyl)propoxymethyl chloride, 2- (triethylsilyl)ethoxymethyl chloride, 2-(triisopropylsilyl)ethoxymethyl chloride, and 2- (dimethylphenylsilyl)ethoxymethyl chloride. Examples [0018] The invention is described by the examples provided below, but the invention is not limited to these examples. In these examples, the gas chromatograms and mass spectra of the reaction products were measured using a GCMS-QP5050A (Shimadzu Corporation). The reaction product was identified by agreement between the measurement results obtained for the reaction product using the GCMS-QP5050A, and the measurement results for a commercially acquired 2-(trimethylsilyl)ethoxymethyl chloride reference material (from Tokyo Kasei). The purity of the purified 2-(trimethylsilyl)ethoxymethyl chloride was calculated from the results of gas chromatographic measurement (GCMS-QP5050A) of the reference material and reaction product by comparing the respective peak area ratios. [0019] Practical Example 1 13.5 g (0.45 mol) of paraformaldehyde and 125.0 g (1.15 mol) of chlorotrimethylsilane were introduced into a 300-mL four-neck flask fitted with a thermometer and stirrer. 54.4 g (0.46 mol) of 2-trimethylsilylethanol was added dropwise over 30 minutes while stirring and cooling with an ice bath. After wanning the reaction mixture to room temperature, the pressure was reduced to 100 mmHg using an aspirator, and the hydrogen chloride was removed. The low boiling fraction was distilled off, and additional vacuum distillation was carried out to provide 34.0 g of 2-(trimethylsilyl)ethoxymethyl chloride. The 2-(trimethylsilyl)ethoxymethyl chloride product had a purity of 76%, and the yield was 33%. [0020] Comparative Example 1 6.0 g (0.2 mol) of paraformaldehyde and 23.7 g (0.2 mol) of 2-trimethylsilylethanol were introduced into a 100-mL four-neck flask fitted with a thermometer and stirrer. Hydrogen chloride gas was bubbled in while stirring and cooling with an ice bath, but the end point of the reaction was unclear. While the production of 2-(trimethylsilyl)ethoxymethyl chloride while on the ice bath was confirmed, the 2-(trimethylsilyl)ethoxyrnethyl chloride produced underwent decomposition when the mixture was warmed to room temperature, and no target material whatever was obtained. [0021] Practical Example 2 6.0 g (0.2 mol) of paraformaldehyde and 108.6 g (1 mol) of chlorotrimethylsilane were introduced into a 200-mL four-neck flask fitted with a thermometer and stirrer. 23.7 g (0.2 mol) of 2-trimethylsilylethanol was added dropwise over 30 minutes while stirring and cooling with an ice bath. After warming the reaction mixture to room temperature, the pressure was reduced to 100 mm Hg using an aspirator, and the hydrogen chloride was removed. After then adding 5 drops of diisopropylethylamine, the low boiling fraction was distilled off, and additional vacuum distillation was carried out to provide 22.9 g of 2-(trimethylsilyl)ethoxymethyl chloride. The purity of the obtained 2-(trimethylsilyl)ethoxymethyl chloride was very high, i.e., 98%, and the yield was 68%. [0022] Practical Example 3 A reaction was carried out under the same conditions as in Practical Example 2, but using 36.1 g (0.2 mol) of 2-dimethylphenylsilylethanol in place of the 2-trimethylsilylethanol. 33.4 g of 2-(dirnethylphenylsilyl)ethoxymethyl chloride was obtained. The purity of the 2-(trimethylsilyl)ethoxymethyl chloride was very high, i.e., 99%, and the yield was 73%. Industrial Applicability [0023] The method in accordance with the invention is useful for the industrial production of silylalkoxymethyl halides such as trimethylsilylmethoxymethyl chloride and phenyldimethylsilylmethoxymethyl chloride. We Claim: 1. A method of manufacturing a silylalkoxymethyl halide of formula (1): wherein R1, R2, and R3 are an alkyl, cycloalkyl, aryl group, or a halogen atom, R4 is a divalent hydrocarbyl group having 1 to 10 carbon atoms, and X is a halogen atom, comprising reacting: (a) a silyl alcohol compound of formula (2): wherein R1, R2, and R3 are an alkyl, cycloalkyl, aryl group, or a halogen atom, and R4 is a divalent hydrocarbyl group having 1 to 10 carbon atoms, with (b) formaldehyde or a polymer thereof, and (c) a halosilane. 2. The method as claimed in Claim 1 comprising additionally distilling out under reduced pressure, hydrogen halide generated as a by-product in the reaction, excess halosilane, and the reaction product of water and halosilane, and thereafter adding (d) a tertiary amine, and purifying the silylalkoxymethyl halide by further distillation. 3. The method as claimed in Claim 1 or 2 wherein the (a) silyl alcohol compound is trialkylsilylethanol, and the silylalkoxymethyl halide is trialkylsilylethoxymethyl halide. 4. The method as claimed in Claim 1 or 2 wherein the (c) halosilane is chlorotrialkylsilane, and the silylalkoxymethyl halide is silylalkoxymethyl chloride. (54) Title: METHOD OF PRODUCING SILYLALKOXYMETHYL HALIDE (57) Abstract: A method for making a silylalkoxymethyl halide at good yield represented by the formula: R1R2 R3Si-R4-O-CH2X wherein R1 , R2 , and R3 are an alkyl, cycloalkyl, aryl group, or a halogen atom, R4 is a divalent hydrocarbyl group having 1 to 10 carbon atoms, and X is a halogen atom, by reacting: (a) a silyl alcohol compound with the formula R1R2 R3Si-R4 -OH wherein R1 , R2 , R3 and R4 arc defined as above, with (b) formaldehyde or a polymer thereof, and (c) a halosilane.

Full Text

DESCRIPTION

Field of the Invention
[0001] This invention relates to a novel method of manufacturing a silylalkoxymethyl
halide, the product being obtained easily and with a high yield.
Background of the Invention
[0002] Silylalkoxymethyl halides are publicly known. Among these compounds,
trimethylsilylmethoxymethyl chloride and phenyldimethylsilylmethoxymethyl chloride in
particular are very important in the synthesis of bio-active substances and natural products
with complex structures as reagents that protect functional groups containing active hydrogen.
[0003] Some examples of synthesis by several methods have already been reported for
silylalkoxymethyl chlorides such as trimethylsilylmethoxymethyl chloride and
phenyldimethylsilylmethoxymethyl chloride (See to Bruce H. Lipshutz et al., Tetrahedron
Letters (Great Britain), Volume 21 (1980), pp. 3343-3346; Denis Guedin-Vunong et al.,
Bulletin de la Societe Chimique de France (France), No. 2 (1986), pp. 245-252; Arthur G.
Schultz et al., Organic Preparations and Procedures International (US), Volume 27 (1995),
pp. 572-574; and G. J. P. H. Boons et al., Tetrahedron Letters (Great Britain), Volume 31
(1990), pp. 2197-2200). These synthesis examples involve chloromethylation of the
corresponding silyl alcohol using hydrogen chloride gas in the presence of a formaldehyde
polymer.
[0004] However, there is a substantial problem to execute this procedure on an industrial
basis. Specifically, the generation of by-product water cannot be avoided during
chloromethylation using hydrogen chloride gas, and this water reacts with the product,
resulting in product decomposition. The result is either a major reduction in the yield of the
target silylalkoxymethyl chloride or a complete failure to obtain the target silylalkoxymethyl
chloride.
[0005] In the aforementioned references, the by-product water is removed from the
system by introducing a dehydrating agent, such as magnesium sulfate, immediately after the

reaction. However, the implementation of this procedure on an industrial basis is
cumbersome and complicated, and the product decomposition also proceeds during the time
required to carry out the dehydration treatment. Moreover, the dehydrating agent must be
separated from the product by, for example, filtration, which lengthens the process time,
increases the amount of waste, raises the production costs, and lowers the yield.
[0006] In addition to the preceding, hydrogen chloride gas is a gaseous reagent and thus
is much more difficult to handle than ordinary liquid reagents. It is difficult, in particular, to
measure the amount used in the reaction, making it necessary to use a large excess of the gas
and thereby raising the costs and increasing the amount of waste.
[0007] A. G. Shipov et al., Zhurnal Obshchei Khimii (formerly the USSR), Volume 59
(1989), pp. 1204-1205, describes a method for manufacturing alkoxymethyl chloride by the
reaction of an aryl alcohol or alkyl alcohol with formula (3)
R-OH (3)
wherein R is phenylmethyl or an alkyl group having 1, 5, 8, 10 or 12 carbon atoms, with
paraformaldehyde in chlorotrimethylsilane. However, this reference does neither describe nor
suggest the use of a silyl alcohol as a starting material.
Summary of the Invention
[0009] This invention solves the problems noted above, and its object is the introduction
of a high yield method of manufacturing silylalkoxymethyl halide. The method does not
require the use of difficult-to-handle hydrogen chloride gas, it does not generate by-product
water, it does not require a dehydrating agent, it generates little solid waste, and it requires
less time for manufacturing silylalkoxymethyl halide than current methods.
[0010] As a result, in accordance with the invention, it has been discovered that a
silylalkoxymethyl halide represented by formula (1):

wherein R1, R2, and R3 are alkyl, cycloalkyl, aryl group, or a halogen atom, R4 is divalent
hydrocarbyl group having 1 to 10 carbon atoms, and X is a halogen atom, could be
synthesized at good efficiencies by reacting
(a) a silyl alcohol compound represented by formula (2):

wherein R1, R2, and R3 are alkyl, cycloalkyl, aryl, or a halogen atom, and R4 is divalent
hydrocarbyl group having 1 to 10 carbon atoms, with
(b) formaldehyde or a polymer thereof, and
(c) a halosilane.
It was also discovered that high purity silylalkoxymethyl halide could be obtained in high
yields by distilling out, under the application of reduced pressure, hydrogen halide generated
as a by-product in the reaction, excess halosilane, and the reaction product of water and
halosilane; and thereafter adding
(d) a tertiary amine, and
distilling the silylalkoxymethyl halide.
[0011] The method of the invention enables a high yield and industrially facile and
efficient synthesis of a silylalkoxymethyl halide represented by formula (1):

wherein R1, R2, and R3 are alkyl, cycloalkyl, aryl, or a halogen atom, R4 is divalent
hydrocarbyl group having 1 to 10 carbon atoms, and X is a halogen atom, without using
either hydrogen chloride gas or a dehydrating agent, and it does so while making it possible
to reduce the amount of solid waste.

Detailed Description of the Invention
[0012] According to the method, the (a) silyl alcohol compound represented by formula
(2):

is the primary starting material. R1, R2, and R3 in formula (2) are alkyl, cycloalkyl, aryl, or a
halogen atom, while R4 is a divalent hydrocarbyl group having 1 to 10 carbon atoms. R1, R2,
and R3 can be specifically exemplified by alkyl groups such as methyl, ethyl, propyl,
isopropyl, butyl, isobutyl, pentyl, isopentyl, hexyl, and isohexyl; cycloalkyl groups such as
cyclopentyl, cyclohexyl, and cycloheptyl; aryl groups such as phenyl, tolyl, xylyl, and
naphthyl; and halogen atoms such as the chlorine atom and fluorine atom. R4 is specifically
exemplified by methylene; alkylene having 2 to 10 carbon atoms such as ethylene, propylene,
and butylene; cycloalkylene having 3 to 10 carbon atoms such as cyclopentylene and
cyclohexylene; and arylene having 6 to 10 carbon atoms such as phenylene and naphthylene.
When the compound represented by formula (1) prepared in accordance with the invention is
used as a reagent for protecting active hydrogen-containing functional groups, R', R2, and
R3 are preferably methyl, ethyl, propyl, isopropyl, or phenyl, and R4 preferably is methylene,
ethylene, or propylene, and more preferably ethylene. The silyl alcohol compound
represented by formula (2) can be specifically exemplified by trimethylsilylmethanol, 2-
trimethylsilylethanol, 3-trimethylsilylpropanol, 2-triethylsilylethanol, 2-
triisopropylsilylethanol, and 2-dimethylphenylsiIylethanol. These silyl alcohol compounds
can in some cases be acquired as reagents, and when necessary can also be synthesized by
known procedures.
[0013] The (b) formaldehyde or polymer thereof is a generally known formaldehyde
equivalent. Usable here are, inter alia, gaseous formaldehyde, trioxane (the trimer), and
paraformaldehyde (a polymer). Granular paraformaldehyde is particularly preferred from the
standpoints of reactivity and ease of handling. Aqueous formalin solutions are undesirable
due to the negative effects exercised by their water fraction. The formaldehyde or polymer

thereof may be used in a small excess, and preferably in the range of 1 to 1.5 equivalents,
with respect to the (a) silyl alcohol compound with formula (2).
[0014] The (c) halosilane functions to react with the silyl alcohol compound and thereby
produces the hydrogen halide required by the halomethylation reaction, and at the same time
functions to scavenge the water generated as a by-product. When the compound represented
by formula (1) prepared in accordance with the invention is used as a reagent for protecting
active hydrogen-containing functional groups, the halosilane is preferably a chlorosilane or a
bromosilane, and more preferably is a chlorosilane. Specific examples are tetrachlorosilane,
methyltrichlorosilane, chlorotrimethylsilane, and chlorotriethylsilane. Chlorotrimethylsilane
is most preferred when one considers its ease of acquisition and ease of separation of the
product after water scavenging. The (c) halosilane is desirably used in excess relative to the
(a) silyl alcohol compound represented by formula (2), wherein 2 to 20 equivalents is
preferred, and 3 to 5 equivalents is more preferred, in each case referred to the (a) silyl
alcohol compound represented by formula (2).
[0015] The reaction among the (a) silyl alcohol compound represented by formula (2),
(b) formaldehyde or polymer thereof, and the (c) halosilane proceeds readily merely upon
mixing the individual components. However, a procedure in which one component is added
dropwise to a mixture of the other components is desirable, in order to avoid an overly
vigorous reaction. More preferably, the reaction is appropriately carried out by adding the (a)
silyl alcohol compound represented by formula (2) dropwise to a mixture of (b)
formaldehyde or polymer thereof, and the (c) halosilane. The reaction temperature is
preferably low, in order to avoid product decomposition and the range of 0 to 10°C is most
preferred. The reaction does not require solvent, but a solvent inert with respect to the
individual components such as toluene, xylene, and heptane can be used when necessary.
[0016] The target material is obtained after the reaction by distilling out, under the
application of reduced pressure, the hydrogen halide, excess halosilane, and water/halosilane
reaction product. Purification by distillation is desirably carried out in order to provide an
additional increase in target material purity. Improvements in the silylalkoxymethyl halide
purity and reaction yield can be obtained by the addition of (d) tertiary amine to this

distillative purification, in order to neutralize the hydrogen halide not completely distilled out
under reduced pressure, and thereby more effectively inhibit product decomposition. This
tertiary amine is preferably triethanolamine or diisopropylethylamine, and is more preferably
diisopropylethylamine.
[0017] Silylalkoxymethyl halide represented by formula (1) prepared by the method in
accordance with the invention can be exemplified by (trimethylsilyl)methoxyethyl chloride,
2-(trimethylsilyl)ethoxymethyl chloride, 3-(trimethylsilyl)propoxymethyl chloride, 2-
(triethylsilyl)ethoxymethyl chloride, 2-(triisopropylsilyl)ethoxymethyl chloride, and 2-
(dimethylphenylsilyl)ethoxymethyl chloride.
Examples
[0018] The invention is described by the examples provided below, but the invention is
not limited to these examples. In these examples, the gas chromatograms and mass spectra of
the reaction products were measured using a GCMS-QP5050A (Shimadzu Corporation). The
reaction product was identified by agreement between the measurement results obtained for
the reaction product using the GCMS-QP5050A, and the measurement results for a
commercially acquired 2-(trimethylsilyl)ethoxymethyl chloride reference material (from
Tokyo Kasei). The purity of the purified 2-(trimethylsilyl)ethoxymethyl chloride was
calculated from the results of gas chromatographic measurement (GCMS-QP5050A) of the
reference material and reaction product by comparing the respective peak area ratios.
[0019] Practical Example 1
13.5 g (0.45 mol) of paraformaldehyde and 125.0 g (1.15 mol) of chlorotrimethylsilane were
introduced into a 300-mL four-neck flask fitted with a thermometer and stirrer. 54.4 g (0.46
mol) of 2-trimethylsilylethanol was added dropwise over 30 minutes while stirring and
cooling with an ice bath. After wanning the reaction mixture to room temperature, the
pressure was reduced to 100 mmHg using an aspirator, and the hydrogen chloride was
removed. The low boiling fraction was distilled off, and additional vacuum distillation was
carried out to provide 34.0 g of 2-(trimethylsilyl)ethoxymethyl chloride. The
2-(trimethylsilyl)ethoxymethyl chloride product had a purity of 76%, and the yield was 33%.

[0020] Comparative Example 1
6.0 g (0.2 mol) of paraformaldehyde and 23.7 g (0.2 mol) of 2-trimethylsilylethanol were
introduced into a 100-mL four-neck flask fitted with a thermometer and stirrer. Hydrogen
chloride gas was bubbled in while stirring and cooling with an ice bath, but the end point of
the reaction was unclear. While the production of 2-(trimethylsilyl)ethoxymethyl chloride
while on the ice bath was confirmed, the 2-(trimethylsilyl)ethoxyrnethyl chloride produced
underwent decomposition when the mixture was warmed to room temperature, and no target
material whatever was obtained.
[0021] Practical Example 2
6.0 g (0.2 mol) of paraformaldehyde and 108.6 g (1 mol) of chlorotrimethylsilane were
introduced into a 200-mL four-neck flask fitted with a thermometer and stirrer. 23.7 g (0.2
mol) of 2-trimethylsilylethanol was added dropwise over 30 minutes while stirring and
cooling with an ice bath. After warming the reaction mixture to room temperature, the
pressure was reduced to 100 mm Hg using an aspirator, and the hydrogen chloride was
removed. After then adding 5 drops of diisopropylethylamine, the low boiling fraction was
distilled off, and additional vacuum distillation was carried out to provide 22.9 g of
2-(trimethylsilyl)ethoxymethyl chloride. The purity of the obtained
2-(trimethylsilyl)ethoxymethyl chloride was very high, i.e., 98%, and the yield was 68%.
[0022] Practical Example 3
A reaction was carried out under the same conditions as in Practical Example 2, but using
36.1 g (0.2 mol) of 2-dimethylphenylsilylethanol in place of the 2-trimethylsilylethanol. 33.4
g of 2-(dirnethylphenylsilyl)ethoxymethyl chloride was obtained. The purity of the
2-(trimethylsilyl)ethoxymethyl chloride was very high, i.e., 99%, and the yield was 73%.
Industrial Applicability
[0023] The method in accordance with the invention is useful for the industrial
production of silylalkoxymethyl halides such as trimethylsilylmethoxymethyl chloride and
phenyldimethylsilylmethoxymethyl chloride.

We Claim:
1. A method of manufacturing a silylalkoxymethyl halide of formula (1):

wherein R1, R2, and R3 are an alkyl, cycloalkyl, aryl group, or a halogen atom,
R4 is a divalent hydrocarbyl group having 1 to 10 carbon atoms, and X is a
halogen atom, comprising reacting:
(a) a silyl alcohol compound of formula (2):

wherein R1, R2, and R3 are an alkyl, cycloalkyl, aryl group, or a halogen atom,
and R4 is a divalent hydrocarbyl group having 1 to 10 carbon atoms, with
(b) formaldehyde or a polymer thereof, and
(c) a halosilane.

2. The method as claimed in Claim 1 comprising additionally distilling out
under reduced pressure, hydrogen halide generated as a by-product in the
reaction, excess halosilane, and the reaction product of water and halosilane,
and thereafter adding (d) a tertiary amine, and purifying the silylalkoxymethyl
halide by further distillation.
3. The method as claimed in Claim 1 or 2 wherein the (a) silyl alcohol
compound is trialkylsilylethanol, and the silylalkoxymethyl halide is
trialkylsilylethoxymethyl halide.
4. The method as claimed in Claim 1 or 2 wherein the (c) halosilane is
chlorotrialkylsilane, and the silylalkoxymethyl halide is silylalkoxymethyl
chloride.

(54) Title: METHOD OF PRODUCING SILYLALKOXYMETHYL HALIDE

(57) Abstract: A method for making a silylalkoxymethyl halide at good yield represented by the formula: R1R2 R3Si-R4-O-CH2X
wherein R1 , R2 , and R3 are an alkyl, cycloalkyl, aryl group, or a halogen atom, R4 is a divalent hydrocarbyl group having 1 to 10
carbon atoms, and X is a halogen atom, by reacting: (a) a silyl alcohol compound with the formula R1R2 R3Si-R4 -OH wherein R1 ,
R2 , R3 and R4 arc defined as above, with (b) formaldehyde or a polymer thereof, and (c) a halosilane.

Documents:

01518-kolnp-2007-abstract.pdf

01518-kolnp-2007-claims.pdf

01518-kolnp-2007-correspondence others.pdf

01518-kolnp-2007-description complete.pdf

01518-kolnp-2007-form 1.pdf

01518-kolnp-2007-form 3.pdf

01518-kolnp-2007-form 5.pdf

01518-kolnp-2007-gpa.pdf

01518-kolnp-2007-international publication.pdf

01518-kolnp-2007-international search report.pdf

01518-kolnp-2007-pct request.pdf

1518-KOLNP-2007-(07-08-2012)-CORRESPONDENCE.pdf

1518-KOLNP-2007-(07-08-2013)-CLAIMS.pdf

1518-KOLNP-2007-(07-08-2013)-CORRESPONDENCE.pdf

1518-KOLNP-2007-(13-02-2012)-ABSTRACT.pdf

1518-KOLNP-2007-(13-02-2012)-AMANDED CLAIMS.pdf

1518-KOLNP-2007-(13-02-2012)-DESCRIPTION (COMPLETE).pdf

1518-KOLNP-2007-(13-02-2012)-EXAMINATION REPORT REPLY RECEIVED.pdf

1518-KOLNP-2007-(13-02-2012)-FORM-1.pdf

1518-KOLNP-2007-(13-02-2012)-FORM-13.pdf

1518-KOLNP-2007-(13-02-2012)-FORM-2.pdf

1518-KOLNP-2007-(13-02-2012)-FORM-3.pdf

1518-KOLNP-2007-(13-02-2012)-OTHERS PCT FORM.pdf

1518-KOLNP-2007-(13-02-2012)-OTHERS.pdf

1518-KOLNP-2007-(13-02-2012)-PETITION UNDER RULE 137-1.pdf

1518-KOLNP-2007-(13-02-2012)-PETITION UNDER RULE 137.pdf

1518-KOLNP-2007-(15-02-2012)-ASSIGNMENT.pdf

1518-KOLNP-2007-(15-02-2012)-CORRESPONDENCE.pdf

1518-KOLNP-2007-(15-02-2012)-PETITION UNDER RULE 137.pdf

1518-KOLNP-2007-ASSIGNMENT.pdf

1518-KOLNP-2007-CANCELLED PAGES.pdf

1518-KOLNP-2007-CORRESPONDENCE-1.1.pdf

1518-KOLNP-2007-CORRESPONDENCE.pdf

1518-KOLNP-2007-EXAMINATION REPORT.pdf

1518-kolnp-2007-form 18.pdf

1518-KOLNP-2007-GPA.pdf

1518-KOLNP-2007-GRANTED-ABSTRACT.pdf

1518-KOLNP-2007-GRANTED-CLAIMS.pdf

1518-KOLNP-2007-GRANTED-DESCRIPTION (COMPLETE).pdf

1518-KOLNP-2007-GRANTED-FORM 1.pdf

1518-KOLNP-2007-GRANTED-FORM 2.pdf

1518-KOLNP-2007-GRANTED-FORM 3.pdf

1518-KOLNP-2007-GRANTED-FORM 5.pdf

1518-KOLNP-2007-GRANTED-SPECIFICATION-COMPLETE.pdf

1518-KOLNP-2007-INTERNATIONAL PUBLICATION.pdf

1518-KOLNP-2007-INTERNATIONAL SEARCH REPORT & OTHERS.pdf

1518-KOLNP-2007-OTHERS.pdf

1518-KOLNP-2007-PETITION UNDER RULE 137.pdf

1518-KOLNP-2007-REPLY TO EXAMINATION REPORT.pdf

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Patent Number

257070

Indian Patent Application Number

1518/KOLNP/2007

PG Journal Number

36/2013

Publication Date

06-Sep-2013

Grant Date

30-Aug-2013

Date of Filing

27-Apr-2007

Name of Patentee

DOW CORNING TORAY CO., LTD.

Applicant Address

1-3, MARUNOUCHI, 1-CHOME, CHIYODA-KU, TOKYO 1000005

Inventors:

#	Inventor's Name	Inventor's Address
1	WAKITA, KEIJI	C/O DOW CORNING TORAY CO., LTD., 2-2, CHIGUSAKAIGAN, ICHIHARA-SHI, CHIBA, 2990108

PCT International Classification Number

C07F 7/08

PCT International Application Number

PCT/JP2005/018405

PCT International Filing date

2005-09-28

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	2004-298875	2004-10-13	Japan