HYDROGEN-CHLORINE EXCHANGE BETWEEN ORGANOSILICON HYDRIDES AND POLYCHLOROALKANES CATALYZED BY RUTHENIUM(II)-PHOSPHINE COMPLEXES

Carbon tetrachloride, 1,1,1-trichloroethane, and 1,1,1,3-tetrachloroalkanes were selectively reduced by silicon hydrides to give chloroform, 1,1-dichloroethane, and 1,1,3-trichloroalkanes, respectively, in high yields in the presence of catalytic amounts of phosphine complexes of ruthenium(II) such as RuCl2(PPh3)3, RuHCl(PPh3)3, RuH2(PPH3)4, and RuH(SiMe2Cl)(PPh3)3. Reactivities of a wide variety of silicon hydrides towards the dechlorination also were estimated. The catalytic cycle can be explained in terms of successive oxidative addition, reductive elimination, and hydrogen-halogen exchange on the ruthenium-phosphine complex. © 1978.