Supported liquid-phase hydroformylation catalysts containing rhodium and triphenylphosphine

Abstract

Catalysts obtained by supporting hydrocarbonyltrist(triphenylphosphine) rhodium(I), HRh(CO)(PPh 3) 3, on silica are active for the hydroformylation of propene. The incorporation of excess PPh 3 into the catalysts leads to an increase in regioselectivity for n-aldehyde production and to a greater stability. An inhibiting effect of excess PPh 3 on the overall activity is dramatically reduced as the level of phosphine incorporation is increased. Preparations containing excess PPh 3 show low activities for the hydrogenation of propene. Evidence is presented for the involvement of excess PPh 3 in a highly mobile, possibly liquid form in some of these catalysts.