Processes for the production of tri-organo-monoalkoxysilanes and process for the production of tri-organo-monochlorosilanes

A process for the production of a tri-organo-monochlorosilane of the general formula (XIIa)

• (R1)(R2)(R3)SiCl (XIIa)
• wherein R1, R2 and R3 are the same as or different from each other and each is a primary, secondary or tertiary alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aralkyl group or an aryl group, but wherein R1, R2 and R3 each and all do not represent methyl group at the same time, or for the production of a tri-organo monochlorosilane of the general formula (XIIb)
• (R1)(R2)(R3a)SiCl (XIIb)
• wherein R1 and R2 have the same meanings as defined above and R3a is a secondary alkyl group or a tertiary alkyl group or a cycloalkyl group, or R3a is an alkyl-substituted aromatic hydrocarbon group of which the alkyl substituent is bonding to a carbon atom present in the aromatic hydrocarbon group characterized in that the process comprises reacting hydrochloric acid with a tri-organosilane compound of the formula (XIa)
• (R1)(R2)(R3)SiZ1 (XIa)
• where R1, R2 and R3 each have the same meanings as defined above and Z1 is a hydrolyzable group, or with a tri-organosilane compound containing the bulky hydrocarbon group R3a therein and having the formula (XIb)
• (R1)(R2)(R3a)SiZ2 (XIb)
• where R1, R2 and R3a have the same meanings as defined above and Z2 is a primary or secondary alkyloxy group, a cycloalkyloxy group or an aralkyloxy group, or Z2 is a 2-substituted or unsubstituted-2-chloroethoxy group of the formula (A)
• where R4 is a hydrogen atom or an alkyl group of 1-8 carbon atoms, or R4 is an alkoxymethylene group, an alkenyloxymethylene group or an aryloxy-methylene group of the formula —CH2—O—R5 where R5 is a straight or branched chain alkyl group of 1-20 carbon atoms or an alkenyl group of 2-10 carbon atoms or an aryl group, thereby to produce a tri-organo-monochlorosilane of the formula (XIIa) or a tri-organo-monochlorosilane of the formula (XIIb).