Application of the Water-gas Shift Reaction. I. Hydrogenation and Hydroformylation Reactions of Olefins with Carbon Monoxide and Water Catalyzed by Rhodium Phosphine Complexes

Article abstract of DOI:10.1246/bcsj.54.3799

The hydrogenation of methyl crotonate with CO and H2O is efficiently catalyzed by RhH2(O2COH)2 or 2/P(i-Pr)3/n-BuLi (C7H8=norbornadiene).Both catalyst precursors are shown to form the same active species; trans-Rh(OH)(CO)2.The catalytic activity of the system (2/phosphine/n-BuLi) increases with increase of the basicity of the phosphine ligands (phosphine=P(i-Pr)3 > P(n-Bu)3 > PPh(i-Pr)2 > PPh2(i-Pr) > PPh3).This reaction is also applicable to the hydrogenation of the C=C bond of electron-withdrawing olefins and the C=O bondof ketones and aldehydes.Interestingly, the catalysis for the C=C bond, to which less electron-withdrawing groups are attached, gives dominantly aldehydes due to hydroformylation.The mechanism is also discussed.