Copper-catalysed asymmetric 1,4-addition of organometallic reagents to 2-cyclohexenone using novel phosphine-phosphite ligands

摘要

A series of novel non-symmetrical phosphine-phosphite ligands 1-10 have been tested in the copper catalysed asymmetric addition of diethylzinc and triethylaluminium to 2-cyclohexenone. In all cases, excellent conversion and regioselectivities for the 1,4-product were found. Good enantiomeric excesses (up to 62%) were obtained when triethylaluminium was used as the alkylating reagent. (C) 2000 Elsevier Science Ltd. All rights reserved. [References: 28]