Homogeneous hydroformylation of alkenes with hydridocarbonyltris-(triphenylphosphine)rhodium(I) as catalyst.

The compound hydridocarbonyltris(triphenylphosphine)rhodium(I), RhH(CO)(PPh3)3, is an efficient catalyst for hydroformylation of alkenes at 25 °C at 1 atm. From alk-1-enes high ratios of straight chain to branched chain aldehydes can be produced. The dependence of rates and products on catalyst and substrate concentration, partial pressures of hydrogen and carbon monoxide, temperature, and added excess of triphenylphosphine are described and the suggested mechanisms discussed in relation to these results. Studies at higher temperature and pressure show that rapid and effective conversion of both a liquid alkene and also propene to give high yields of straight chain aldehyde can be achieved particularly when molten triphenylphosphine provides the solvent phase.