Ketone hydrosilylation by Cu(I) diphosphine complexes: A kinetic study

Diphosphine ligands are commonly used for the catalytic hydrosilylation of ketones using Cu(I) complexes. While some DFT studies on the suggested catalytic cycle have been reported, we present herein a complete kinetic study of the copper(I) catalyzed reaction to verify the plausibility of the proposed catalytic cycle from an experimental point of view. The rate constants of the two consecutives steps are determined for BDP (BDP = 1,2-bis(diphenylphosphino)benzene) and rac-BINAP ligands. The two constants are found not to differ significantly, i.e. no rate limiting step is identified. Depending on operation conditions, a switch between rate limiting steps is observed leading to either first order kinetics in silane or ketone.