Abstract: A process for the production of organosilicon compounds of the formula (RO)3−mRmSi—Alk—Sn—Alk—SiRm(OR)3−m where R is independently a monovalent hydrocarbon of 1 to 12 carbon atoms, Alk is a divalent hydrocarbon of 1 to 18 carbon atoms; m is an integer of 0 to 2, n is a number from 1 to 8 is disclosed. The process comprises: (A) reacting sulfur, a phase transfer catalyst, a sulfide compound having the formula M2Sn or MHS, where H is hydrogen, M is ammonium or an alkali metal, n is the same as above,  and water to form an intermediate reaction product; (B) reacting said intermediate reaction product with  a silane compound of the formula; (RO)3−mRmSi—Alk—X  where X is Cl, Br or I, and m is the same as above. The invention provides an improvement process characterized by adding the phase transfer catalyst to the aqueous phase prior to mixing the aqueous phase with the silane compound for the reaction.