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In methanol; hexane; water; at 20℃; for 3h;Product distribution / selectivity;
4. COMPARATIVE EXAMPLE 5-2; [00160] The same reaction procedures as in Comparative Example 5-1 were repeated except that trimethylchlorosilane was used in place of triethylchlorosilane. GC analysis of the obtained crude product revealed that 3-tris(trimethylsiloxy)silylpropyl methacrylate was obtained at a ratio of 69.8 % in terms of GC area % as a major product.
With pyridine; In methanol; hexane; water; at 2 - 20℃; for 3h;
12. Comparative Example 5-2 The same reaction procedures as in Comparative Example 5-1 were repeated except that trimethylchlorosilane was used in place of triethylchlorosilane. GC analysis of the obtained crude product revealed that 3-tris(trimethylsiloxy)silylpropyl methacrylate was obtained at a ratio of 69.8% in terms of GC area % as a major product.
Example 9 A 1000-ml four necked glass flask equipped with a reflux condenser, thermometer and stirrer was purged with nitrogen. The flask was charged with 406.0 g (2.5 mol) of hexamethyldisiloxane and 64.0 g (2.0 mol) of methanol, and cooled in an ice water bath to an internal temperature below 10C. To the flask kept at an internal temperature of 5-10C, 9.8 g (0.1 mol) of conc. sulfuric acid was added dropwise over 30 minutes, and stirring was continued at the temperature for 30 minutes. Subsequently, to the flask kept at an internal temperature of 5-10C, 248.4 g (1.0 mol) of 3-methacryloxypropyltrimethoxysilane was added dropwise over 30 minutes, and stirring was continued at the temperature for one hour. At an internal temperature of 5-25C, 72.0 g (4.0 mol) of water was added dropwise over one hour. After the completion of dropwise addition, stirring was continued at 15-25C for 6.5 hours. The reaction solution was subjected to separatory operation to remove the aqueous layer. The organic layer was washed with water and separated again. The resulting organic layer of the reaction solution was analyzed by GC, finding that the area percent ratio of the main product to monomethoxy and monohydroxy compounds, 3-MAPSi(OSiMe3)3/[3-MAPSi(OMe)(OSiMe3)2 + 3-MAPSi(OH) (OSiMe3)2] was 22.5. The total content of monomethoxy and monohydroxy compounds was 0.044 mol, as determined from the area percents by GC. While the organic layer was kept at a temperature of 20-25C, 24.5 g (0.25 mol) of conc. sulfuric acid was added dropwise over 15 minutes, and stirring was continued at the temperature for one hour. The organic layer after reaction with sulfuric acid was analyzed by GC, finding that the area percent ratio of the main product to monomethoxy and monohydroxy compounds, 3-MAPSi(OSiMe3)3/[3-MAPSi(OMe)(OSiMe3)2 + 3-MAPSi(OH)(OSiMe3)2] was 358.3. The sulfuric acid layer was removed from the reaction solution, after which the organic layer was washed with water, neutralized with aqueous sodium bicarbonate, and washed with water again. On distillation of the resulting organic layer, 393.5 g (0.93 mol) of 3-methacryloxypropyltris(trimethylsiloxy)silane with a purity of 99.6% was collected as a fraction having a boiling point of 118.5-120.5C/0.2 kPa. The yield was 93.1%.
EXAMPLE 1 3-methacryloxypropyltris(trimethylsiloxy)silane In a three-neck flask, 75.4 g (0.47 mol) of hexamethyldisiloxane, 39.9 g (0.67 mol) of acetic acid, 8.7 g of sulfuric acid (conc.) (0.09 mol) and 0.5 g of a 10% solution of trifluoromethanesulfonic acid in acetic acid (0.0003 mol) are initially introduced and stirred at -15 C. to -5 C. At this temperature, 55.0 g (0.22 mol) of 3-methacryloxypropyltrimethoxysilane (Wacker GENIOSIL GF 31) are metered in over the course of one hour. The mixture is then heated to room temperature and after-stirred for 2 h. After separating off the acidic lower phase from the organic layer, the organic phase is analyzed by means of GC: the following are found (besides the readily volatile constituents): product 49.6 area %; monoorganoxy impurity CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OMe (0.2 area %); monohydroxy impurity (CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OH (0.5 area %) and 0.5 area % of the difunctional disiloxane (dimers) [CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2]O. To reduce the content of monohydroxysilane, at room temperature, 18.7 g (0.11 mol) of hexamethyldisilazane are added (1 h) and after-stirred for 1 h. Following the reaction and neutralization with HMN and removal by filtration of the formed salt, the following constituents are identified in the crude product in the GC besides readily volatile constituents: product (45.5 area %); monoorganoxy impurity CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OMe (0.2 area %); monohydroxy impurity CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OH (0.0 area %) and 0.3 area % of the difunctional disiloxane (dimers) [CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2]O. After distilling off the low-boiling components, the crude product has the following purities: product (97.8 area %); monoorganoxy impurity CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OMe (0.2 area %); monohydroxy impurity CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OH (0.0 area %) and 0.6 area % of the difunctional disiloxane (dimers) [CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2]O. Following distillation and fine filtration (filter candle), the product 3-methacryloxypropyltris(tri-methylsiloxy)silane is obtained in 83% yield, the following GC contents being obtained: product (99.5 area %); monoorganoxy impurity CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OMe (0.2 area %); monohydroxy impurity CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OH (0.0 area %) and 0.0 area % of the difunctional disiloxane (dimers) [CH2=CH(CH3)-COO-(CH2)3-Si(OSiMe3)2]O.
80%
EXAMPLE 13-methacryloxypropyltris(trimethylsiloxy)silaneIn a three-neck flask, 80.8 g (0.499 mol) of hexamethyldisiloxane, 39.9 g (0.67 mol) of acetic acid and 0.5 g of a 10% solution of trifluoromethanesulfonic acid in acetic acid (0.0003 mol) are initially introduced and heated to 45 C. with stirring. Then, over the course of one hour (at 45 C.), 55.0 g (0.22 mol) of 3-methacryloxypropyl-trimethoxysilane (WACKER GENIOSIL GF 31) are added and after-stirred for 1 h at 45 C. The crude product is analyzed by means of gas chromatography (GC). Besides the readily volatile constituents of the reaction mixture, the following GC contents are found: product (44.3 area %); monoorganoxy impurity CH2CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OMe (1.1 area %); monohydroxy impurity CH2CH(CH3)-COO-(CH2)3Si(OSiMe3)2OH (0.6 area %), and 0.5 area % of the difunctional disiloxane (dimers) [CH2CH(CH3)-COO-(CH2)3-Si(OSiMe3)2]O.At 45 C., 13.1 g (0.167 mol) of acetyl chloride are added to the reaction mixture (over the course of 10 min), before the mixture is after-stirred for 10 min. At room temperature, an acidic phase is separated off from the organic layer before the reaction mixture is analyzed again by gas chromatography. The following are found: product (50.0 area %); monoorganoxy impurity CH2CH(CH3)-COO-(CH2)3Si(OSiMe3)2OMe (0.1 area %); monohydroxy impurity CH2CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OH (0.5 area %) and 0.8 area % of the difunctional disiloxane (dimers) [CH2CH(CH3)-COO-(CH2)3-Si(OSiMe3)2]O.In order to eliminate/reduce the remaining content of monohydroxysilane impurity, 18 g (0.12 mol) of hexamethyl-disilazane are added, the reaction mixture being neutralized at the same time. After filtering off the formed salts, the reaction mixture is again analyzed by means of GC. The following are found: product (44.6 area %); monoorganoxy impurity CH2CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OMe (0.1 area %); monohydroxy impurity CH2CH(CH3)-COO-(CH2)3-Si(OSiMe3)2OH (0.0 area %) and 0.8 area % of the difunctional disiloxane (dimers) [CH2CH(CH3)-COO-(CH2)3-Si(OSiMe3)2]O.After distilling off the volatile constituents, the product is distilled in vacuo and filtered off via a filter candle. The desired product is obtained in a yield of 80% and has a purity of 99.6 area % (contains 0.1 area % monoorganoxysilane). The specified monohydroxy and disiloxane impurities can no longer be detected.
With trifluorormethanesulfonic acid; 2,6-di-tert-butyl-4-methyl-phenol; at 80℃; for 1h;Dean-Stark; Inert atmosphere;
To a 500 mL three-necked flask equipped with a constant pressure funnel, magnetic stirrer, Dean-Stark tube and condenser, under nitrogen 124.18 g (0.5 mol) Methacryloxypropyltrimethoxysilane was added, 0.15 g of trifluoromethanesulfonic acid, 0.15 g of BHT was heated to 80 C and 198.35 g (1.5 mol) of acetoxytrimethylene was added dropwise to the reaction flask through a constant pressure funnel. As the dropwise addition progressed, most of the low boiling by-products were continuously distilled off and collected from the Dean-Stark tube side tube. After completion of the addition, stirring was continued for 1 hour. The reaction product was transferred to a separatory funnel and washed with water (100 mL) six times to obtain a neutral colorless transparent liquid. A small amount of low boiling substance was removed by rotary evaporation under reduced pressure to obtain 198.08 g of methacryloxypropyltris(trimethylsiloxy)silane in a yield of 93.7%.
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