A convenient synthesis of enantiopure mixed donor phosphine-phosphite ligands has been developed incorporating P-stereogenic phosphanorbornane and axially chiral bisnaphthols into one ligand structure. The ligands were applied in Pd-catalyzed asymmetric allylic substitution of diphenylallyl acetate, Rh-catalyzed asymmetric hydroformylation of styrene and Rh-catalyzed asymmetric hydrogenation of an acetylated dehydroamino ester. Excellent branched selectivity was observed in the hydroformylation although low ee was found. Moderate ee's of up to 60% in allylic substitution and 50% in hydrogenation were obtained using bisnaphthol-derived ligands.
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