Enantioselective Iron/Bisquinolyldiamine Ligand-Catalyzed Oxidative Coupling Reaction of 2-Naphthols

摘要

An iron-catalyzed asymmetric oxidative homo-coupling of 2-naphthols for the synthesis of 1,1′-Bi-2-naphthol (BINOL) derivatives is reported. The coupling reaction provides enantioenriched BINOLs in good yields (up to 99%) and moderate enantioselectivities (up to 81:19 er) using an iron-complex generated in situ from Fe(ClO ) and a bisquinolyldiamine ligand [(1 ,2 )- , -di(quinolin-8-yl)cyclohexane-1,2-diamine, ]. A number of ligands ( – ) and the analogs of , with various substituents and chiral backbones, were synthesized and examined in the oxidative coupling reactions.