Axially chiral C2-symmetric N-heterocyclic carbene (NHC) palladium complexes-catalyzed asymmetric arylation of aldehydes with arylboronic acids

Chiral C-2-symmetric N-heterocyclic carbene (NHC) palladium diaquo complexes 5a-c and the chiral C-2-symmetric NHC-palladium complexes 5d and 5e prepared from (R)-BINAM or H-8-(R)-BINAM could be used as the catalysts for the enantioselective arylation of arylaldehydes with arylboronic acids in which NHC-Pd complex 5a was found to be fairly effective in this reaction to give the corresponding adducts in moderate enantioselectivities along with moderate to good yields. (C) 2010 Elsevier Ltd. All rights reserved.