Abstract: Rhodium(Ⅰ) complexes prepared from the reaction between Rh₂(CO)₄Cl₂ and the salts of aminophenol, 8-hydroxyquinoline and leucine respectively can catalyze the hydroformylation of styrene at 0.1 MPa and 60℃.The results show that the kind of phosphine ligands plays a crucial role in determining the catalyst activity and regioselectivity.Diphosphine ligands can induce a higher catalyst activity and regioselectivity to the branched aldehyde than PPh3.Triph-enylphosphite promotes the formation of normal aldehyde.Increasing the P/Rh ratio leads to a decrease of initial activity, nevertheless, the higher conversion can be obtained in the case of higher P/Rh ratio.The variation of P/Rh ratio does not affect the regioselectivity apparently.Dicarbonyl leucinatorhodium combined with diphosphines offers a high selectivity to 2-phenyl-propanal, furthermore, it can also be used as an asymmetric catalyst for the hydroformylation of styrene.The optical yield is 9.5% in the presence of Ph₂P(CH₂)₃PPh₂ at a P/Rh ratio of 5.

Key words: Chelate rhodium complexes, Styrene, Hydroformylation, Catalysis