Abstract The reaction of sodium trichloroacetate with various organosilicon hydrides in 1,2-dimethoxyethane was investigated and the products, α-triorganosilyldichloromethanes, were formed in yields of 20–50%. The relative rate constants of these hydrosilanes in such insertion reactions of dichlorocarbene were determined by means of competition reactions. The relative reactivities of a series of alkyl substituted hydrosilanes correlate well with the Taft σ* constants for the substituents on silicon, with a ϱ* value of −1.07, and a series of aryl substituted hydrosilanes also shows good linear correlation of the log k rel values with Taft σ* constants, giving ϱ* value of −1.18. The hydrogen isotope effect in the reaction, k H/ k D 1.26 ± 0.02. Based on the observed results, it was concluded that the insertion of CCl 2 into the SiH bond proceeds by a three-center concerted process in which charge separation in the transition state is not large, as suggested by Seyferth for the related PhHgCCl 2Br/XC 6H 4SiMe 2H reactions.