Patent ID: 8163950

Claim:
A process for the production of a tri-organo-mono-(alkoxy, cycloalkyloxy or aralkyloxy)silane containing a bulky hydrocarbon group or groups R therein and having the formula (XXVa) R 3−(x+y) (R 1 )x(R 2 ) y Si(OR 7 ) (XXVa) wherein R 1 stands for a primary, secondary or tertiary alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aryl group or an aralkyl group, R 2 stands for a secondary alkyl group, a tertiary alkyl group, a cycloalkyl group or an aryl group, and wherein R stands for a secondary alkyl group or a tertiary alkyl group or a cycloalkyl group, or R stands for an alkyl-substituted aromatic hydrocarbon group as defined below, and R 7 has the same meaning as R 3 defined below, or R 7 is a group of the formula —CH 2 —CH(R)—R 4 where R and R 4 have the same meaning as defined below, and x stands for an integer of 0 or 1 and y stands for an integer of 0, 1 or 2, where the integers for x and y are to be within the range of 0≦(x+y)≦2, characterized in that the process comprises reacting tetrachlorosilane or a di or mono-organo-di or trichlorosilane of the formula (XXI) (R 1 )x(R 2 ) y SiCl 4−(x−y) (XXI) wherein R 1 and R 2 have the same meanings as defined above and x and y each stand for an integer as defined above, with a Grignard reagent of the formula (XXII) RMgX (XXII) wherein R stands for a secondary alkyl group or a tertiary alkyl group or a cycloalkyl group, or R stands for an alkyl-substituted aromatic hydrocarbon group of which the alkyl substituent is bonding to a carbon atom present in the aromatic hydrocarbon group, with said carbon atom being adjacent to the carbon atom of the aromatic hydrocarbon group that is bonding to the magnesium atom, and X stands for a chlorine, bromine or iodine atom, in a manner such that the reaction of tetrachlorosilane or the di or trichlorosilane of the formula (XXI) with the Grignard reagent of the formula (XXII) is effected with addition of and reaction with an alcohol of the formula (XXIII) R 3 OH (XXIII) wherein R 3 stands for a primary or secondary alkyl group, a cycloalkyl group or an aralkyl group, or an alkylene oxide or a glycidylether of the formula (XXIV) wherein R 4 stands for a hydrogen atom or an alkyl group of 1-8 carbon atoms, or R 4 stands for an alkoxymethylene group, an alkenyloxymethylene group or an aryloxymethylene group of the formula —CH 2 —O—R 5 where R 5 is a straight or branched chain alkyl group of 1-20 carbon atoms, an alkenyl group of 2-10 carbon atoms or an aryl group.