Theoretical studies of cobalt(I)-catalyzed hydroacylation of vinylsilanes and alkyl aldehydes

Abstract

Density functional theory (DFT) was used to investigate computationally cobalt(I)-catalyzed hydroacylation of vinylsilanes and alkyl aldehydes to give ketones. Calculation indicated that cobalt(I)-catalyzed hydroacylation had eight possible reaction pathways. In the cobalt-hydride complexes IM2a and IM2b, the hydrogen migration occurred prior to the carbon–carbon bond-forming reaction. In the complexes IM3a1 and IM3b1, the carbonyl elimination reaction occurred prior to the direct reductive elimination reaction. In the cobalt–carbonyl complexes IM4a and IM4b, the carbonyl insertion reaction was much easier to achieve than the decarbonylation reaction. The dominant reaction pathway was the reaction channel IM1a TS1a IM2a TS2a1 IM3a1 TS4a IM4a TS5a IM5a TS6a IM6a, and the reductive elimination reaction was the rate-determining step for this channel, so the dominant product predicted theoretically was the linear ketone. Furthermore, the solvation effect was remarkable, and it decreased generally the free energies of the species. Copyright © 2015 John Wiley & Sons, Ltd.