Catalysts and carriers therefor

A process for the preparation of an organosilicon product which comprises reacting in the presence of a composition of matter which is an inorganic particulate solid having chemically bonded to the surface thereof at least one group of the general formula

• -- O -- Si { OSiR'".sub.2 } .sub.n R' -- SR"
• wherein the R substituents are the same or diffferent and are selected from the group consisting of a chlorine atom, a bromine atom, a monovalent radical having from 1 to 8 inclusive carbon atoms and free of aliphatic unsaturation which is a hydrocarbon radical, a halogenated hydrocarbon radical, an oxyhydrocarbon radical, an oxime radical having less than 14 carbon atoms, an oxygen atom and the radical --NQ.sub.2 in which each Q represents a hydrogen atom or an alkyl or an aryl radical having less than 10 carbon atoms, R' represents a divalent hydrocarbon radical having from 1 to 16 inclusive carbon atoms, R" and R'" represents a monovalent hydrocarbon radical free of aliphatic unsaturation and having from 1 to 8 inclusive carbon atoms and n is 0 or an integer of 1 to 20, the sulfur atom in said group being coordinatively bonded to an atom of platinum or rhodium, (1) an organosilicon substance having in the molecule at least one silicon-bonded hydrogen atom and (2) an organic or organosilicon substance containing aliphatic carbon atoms linked by multiple bonds.