Metal complex-catalyzed redistribution reactions of organosilanes : IV. Redistribution reactions of methylsiloxanes catalyzed by transition metal complexes

Abstract

Redistribution reactions of a variety of hydrogen-substituted siloxanes are catalyzed by various transition metal complexes of iridium and rhodium. The products arise from breaking and remaking of Si---C, Si---H, and Si---O bonds. Siloxanes not possessing a Si---H bond are inert under the conditions studied. The most favored reaction pathway appears to scramble preferentially the groups directly attached to the silicon bearing the hydrogen atom. A new cyclo-iridiadisiloxane, L2(CO)(H)IiMeR) (L = Ph3P; R = Me3SiO) is reported. This compound exists in three isomeric forms as a consequence of the spatial arrangements of the R and Me groups on the ring.