Multinuclear Catalyst for Copper-Catalyzed Asymmetric Conjugate Addition of Organozinc Reagents
作者:Kohei Endo、Mika Ogawa、Takanori Shibata
DOI:10.1002/anie.200906839
日期:2010.3.22
A whole lot o' metal: An efficient copper‐catalyzed asymmetric conjugate addition was achieved using a binol‐derived ligand. The catalytic system has a turnover number of 2000, and the excellent catalytic performance could be attributed to the generation of a multinuclear complex such as 1. binol=2,2′‐dihydroxy‐1,1′‐binaphthyl.
Newly designed phosphino-phenol 1c was found to be an efficient chiral auxiliary for copper-mediated asymmetric conjugate addition of diethylzinc to acyclicenones. High enantioselectivity up to >99% ee was achieved in the reaction of acyclic α,β-enones.
Functionalization of BINOL-mono-PHOS achieved the Cu-catalyzed highly asymmetric conjugateaddition of organozincreagents to enones. The incorporation of a bulky hydroxy group at the 3′-position o...
asymmetric conjugate addition (ACA) of diethylzinc to various (E)-alkenyl aryl ketones where the aryl ring is either a phenyl group substituted by nitro, chloro or methoxy groups or not substituted, or a naphthyl group. When the conjugate addition was performed in the greener AcOEt solvent with 1 or 2 mol % of Cu(OTf)2/DiPPAM complex, moderate to good yields (45–83%) and high enantioselectivities (up to 98%)