Poly(siloxane)-supported decacarbonyldimanganese(0) catalyst for terminal olefin hydrosilylation reactions: the effect of the support on the catalyst selectivity, activity and stability

A new class of supported carbonyl manganese catalyst was prepared by treating the dimeric decacarbonyldimanganese(0), Mn,(CO),,, with insoluble aminated poly(siloxane) surface. Solid state FT-IR spectra indicated that the supported catalyst is a dimeric complex that is substituted with two amine ligands, one at each Mn atom. The supported manganese complex was investigated as catalyst for the hydrosilylation reaction of terminal olefins. Contrary to the homogeneous Mn,(CO),, catalytic system, the supported manganese complex was completely selective toward the hydrosilylation reaction with no detectable olefin isomerization or other side-reaction products. Furthermore, the catalyst was selective to produce the linear hydrosilylation product rather than the branched one. No lowering in catalyst activity due to the support was observed. A good proportion of the catalyst activity after separation and reuse was retained for at least four times. Highly reproducible catalytic activity measurements were obtained with catalytic samples taken from same prepared batch. Different prepared batches showed lower reproducibility. The effect of different reaction parameters, such as the solvent effect, the temperature effect, the concentration effect and the added-ligand effect have also been studied. Laine's kinetic studies indicated that the cluster remained intact during the reaction. (C) 1999 Elsevier Science B.V. All rights reserved.