Gold(I)-Catalyzed Asymmetric Synthesis of Planar Chiral Arene Chromium Complexes
作者:Masato Murai、Jun’ichi Uenishi、Motokazu Uemura
DOI:10.1021/ol1019376
日期:2010.11.5
Gold(I)-catalyzed asymmetric cyclization of 1,3-dihydroxymethyl-2-alkynylbenzene chromium complexes gave planar chiral isochromene chromium complexes with high enantioselectivity. Enantiomeric excess of the cyclization products was largely affected by a combination of axially chiral diphosphine(AuCl)(2) precatalysts and silver salts. A system of segphos(AuCl)(2) with AgBF4 resulted in the formation of the corresponding antipode.
Gold(I)-Catalyzed Asymmetric Desymmetrization of<i>meso-</i>Alkynyl Diols and Kinetic Resolution of the Corresponding<scp>dl</scp>-Diols: Effects of Celite Filtration and Silver Salts
The asymmetric desymmetrization of meso‐2‐alkynylbenzenediols through the use of a combination of axially chiral diphosphine(AuCl)2 precatalysts and silver salt co‐catalysts gave optically active isochromene compounds with high enantioselectivities in good yields. The corresponding dl‐diol isomers underwent efficient kinetic resolution to give the cyclized isochromenes and recovered diols with high enantioselectivities