Synthesis of a chiral N-heterocyclic carbene bearing a m-terphenyl-based phosphate moiety as an anionic N-substituent and its application to copper-catalyzed enantioselective boron conjugate additions
作者:Tomohiro Iwai、Yuki Akiyama、Masaya Sawamura
DOI:10.1016/j.tetasy.2013.05.013
日期:2013.6
A chiralN-heterocycliccarbene (NHC) ligand 1a bearing a m-terphenyl-based phosphate moiety as an anionic N-substituent has been developed. A rhodium complex [Rh(1a)(cod)]2 was synthesized and its structure was characterized by NMR and ESI-MS spectroscopy. This ligand gave high enantioselectivities in copper-catalyzed enantioselective boron conjugate additions to an α,β-unsaturated ester to give a