Asymmetric Hydroformylation of Styrene Catalyzed by Pyranoside Diphosphite-Rh(I) Complexes

Abstract

Abstract Several chiral aryl diphosphite ligands derived from pyranoside backbones of glucose and galactose were applied in Rh-catalyzed asymmetric hydroformylation of styrene. A synergistic effect between the chiralities of glucose and the binaphthyl moieties was observed. The sense of enantioselectivity is mainly controlled by the binaphthyl moieties, and the chirality of the sugar moiety can also affect the enantioselectivity of the reactions. In the case of the matching combination of phenyl-3,6-anhydro- β -D-glucopyranoside and binaphthyl moiety, 4-bis{[( S )-1,1′-binaphthyl-2,2′-diyl]-phosphite}-phenyl-3,6-anhydro- β -D-glucopyranoside (L 4 ), 41% ee, and 74:26 of branch-to-normal ratio were obtained.