NOVEL HETEROBIDENTATE LIGANDS FOR ASYMMETRIC CATALYSIS - SYNTHESIS AND RHODIUM-CATALYZED REACTIONS OF S-ALKYL (R)-2-DIPHENYLPHOSPHINO-1,1'-BINAPHTHYL-2'-THIOL

Atropisomerically pure S-alkyl (R)-2-diphenylphosphino-1,1'-binaphthyl-2'-thiol derivatives have been synthesized through a multistep reaction sequence starting from (R)-binaphthol. Pd(II) and Rh(I) complexes containing the 3-methyl derivative 14 as a chelate ligand have been prepared and characterized. Rh(I) complexes containing 14 or the S-iso-propyl derivative 15 effectively catalyse the asymmetric hydroformylation of styrene and the hydrogen transfer reduction of acetophenone.