A new hybrid phosphorus ligand has been prepared starting from chiral NOBIN (2-amino-2'-hydroxy-1,1'-binaphthyl). Excellent enantioselectivities (up to 99% ee) have been achieved in the Rh-catalyzed asymmetric hydroformylations of styrene derivatives and vinyl acetate.

A new pyrrole-based tetraphosphorus ligand capable of forming multiple chelating modes has been prepared. Higher regioselectivity has been achieved in the rhodium-catalyzed isomerization-hydroformylations of internal olefins compared with its bisphosphorus analogue.

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A new class of substituted tetraphosphane ligands has been developed and applied in the rhodium-catalyzed regioselective hydroformylation of terminal olefins. The high regioselectivity (linear selectivity is above 97 % for 1-octene and 1-hexene) at high temperature (140 degrees C) shown by these tetraphosphane ligands is remarkable considering the low regioselectivity commonly observed under similar reaction conditions when other bisphosphane analogues are used. The steric and electronic effects of substituents on the diarylphosphane moiety have also been examined.

A series of hybrid phosphine-phosphoramidite ligands has been designed and synthesized in moderate yields from chiral BINOL (1,1'-bi-2-naphthol) or NOBIN (2-amino-2'-hydroxy-1,1'-binaphthyl). They have achieved highly regio- and enantioselectivities in Rh-catalyzed asymmetric hydroformylations of styrene derivatives (branched/linear ratio up to 56.6, ee up to 99 %), vinyl acetate derivatives (up to 98 % ee), and allyl cyanide (up to 96 % ee). Systematic variation of ligand structure showed that the steric factor on the phsophoramidite moiety determined the performance of the ligand. With the increased hindrance, the branched/linear ratio rose, while the ee value dropped in the hydroformylation of styrene. However, the N-substituents did not influence the selectivities much.