From time to time reference has been made to the effects of steric hindrance in connection with the preparation and reactions of certain organosilicon compounds. Cusa and Kipping (1) were unable to prepare sym-tetracyclohexyldiphenyldisiloxane from dicyclohexylphenylsilanol and they attributed this failure to steric factors. Schumb and Saffer (2) showed that in the reaction of silicon tetrachloride with p-, m-, and o-tolylmagnesium ...