| 摘要 |
Acyloxysilanes are prepared by reacting a chlorosilane with an aliphatic carboxylic acid in a column at an elevated temperature and preferably at a pressure of about 760 mm Hg. wherein the aliphatic carboxylic acid in the vapor phase passes upward from the bottom of the column countercurrent to the flow of the chlorosilane passing downward in the column. The improvement comprises introducing the carboxylic acid into the column at such a rate that the carboxylic acid exceeds 1.3 moles per gram atom of silicon-bonded chlorine in the column and removing low boiling reaction by-products from the top of the column while collecting the acyloxysilane product dissolved in the aliphatic carboxylic acid at the bottom of the column. In a preferred embodiment, methyltriacetoxysilane is prepared by reacting methyltrichlorosilane with acetic acid in a heated fractionation column.
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