A C2-symmetrical aryl diphosphite derived from chiral binaphthol was prepared and its rhodium complex was used as catalysts in the asymmetric hydroformylation of olefins. High catalytic activity and good regioselectiv...A C2-symmetrical aryl diphosphite derived from chiral binaphthol was prepared and its rhodium complex was used as catalysts in the asymmetric hydroformylation of olefins. High catalytic activity and good regioselectivity were observed. Up to 31.2% ee and 38.1% ee were achieved for the hydroformylation of 4-fluoro-styrene and vinyl acetate respectively. The influences of ligand-to-metal ratio, reaction temperature and the pressure of syn-gas on the enantioselectivity and regioselectivity were also studied.展开更多
A series of chiral phosphite ligands based on chiral binaphthol have been designed and synthesized. Their Rhodium(I) complexes were found to be efficient catalysts for the asymmetric hydroformylation of styrene and vi...A series of chiral phosphite ligands based on chiral binaphthol have been designed and synthesized. Their Rhodium(I) complexes were found to be efficient catalysts for the asymmetric hydroformylation of styrene and vinyl acetate and showed excellent catalytic activities and chemos- electivities as well as good regioselectivities (branched aldehyde/linear aldehyde). The enantioselectivities up to 37.0% ee and 38.1% ee were achieved in the hydroformylation of styrene and vinyl acetate respectively. The chiral bidentate phosphite ligands provided better enantioselectivities, however lower regioselectivities than the chiral mono-dentate phosphite ligand.展开更多
Rhodium complex in situ formed by (R)PPhos (4,4’,6,6’tetramethoxy2,2’bis(diphenylphosphino)1,1’bipyridine) with the available rhodium precursors are used for the asymmetric hydroformylation of styren...Rhodium complex in situ formed by (R)PPhos (4,4’,6,6’tetramethoxy2,2’bis(diphenylphosphino)1,1’bipyridine) with the available rhodium precursors are used for the asymmetric hydroformylation of styrene.Effects of total pressure,temperature and the ratio of phosphine/rhodium on catalytic activity,chemoand enantioselectivity are discussed.(R)PPhosRh shows higher activity and regioselectivity and the enantioselectivity is as much as that catalyzed by (S)BINAPRh in the in situ asymmetric hydroformylation of styrene.展开更多
基金Project supported by the Suzhou University and the Hong Kong Polytechnic University ASD Fund and University Grants Committee Area of Excel-lence Scheme in Hong Kong (AoE P/10-01).
文摘A C2-symmetrical aryl diphosphite derived from chiral binaphthol was prepared and its rhodium complex was used as catalysts in the asymmetric hydroformylation of olefins. High catalytic activity and good regioselectivity were observed. Up to 31.2% ee and 38.1% ee were achieved for the hydroformylation of 4-fluoro-styrene and vinyl acetate respectively. The influences of ligand-to-metal ratio, reaction temperature and the pressure of syn-gas on the enantioselectivity and regioselectivity were also studied.
基金supported by the Research Starting Funds of Suzhou University(Grant No.Q4109308)ASD Funds of Hong Kong Polytechnic University.
文摘A series of chiral phosphite ligands based on chiral binaphthol have been designed and synthesized. Their Rhodium(I) complexes were found to be efficient catalysts for the asymmetric hydroformylation of styrene and vinyl acetate and showed excellent catalytic activities and chemos- electivities as well as good regioselectivities (branched aldehyde/linear aldehyde). The enantioselectivities up to 37.0% ee and 38.1% ee were achieved in the hydroformylation of styrene and vinyl acetate respectively. The chiral bidentate phosphite ligands provided better enantioselectivities, however lower regioselectivities than the chiral mono-dentate phosphite ligand.
文摘Rhodium complex in situ formed by (R)PPhos (4,4’,6,6’tetramethoxy2,2’bis(diphenylphosphino)1,1’bipyridine) with the available rhodium precursors are used for the asymmetric hydroformylation of styrene.Effects of total pressure,temperature and the ratio of phosphine/rhodium on catalytic activity,chemoand enantioselectivity are discussed.(R)PPhosRh shows higher activity and regioselectivity and the enantioselectivity is as much as that catalyzed by (S)BINAPRh in the in situ asymmetric hydroformylation of styrene.
