Catalytic Enantioselective Homoaldol Reactions Using Binol Titanium(IV) Fluoride Catalysts
作者:James L. Gleason、E. Diane Burke、Ngiap Kie Lim
DOI:10.1055/s-2003-37122
日期:——
Titanium (IV) fluoride catalysts, prepared by the combination of (R)-2,2'-binaphthol and TiF 4 , are effective for promoting the homoaldol addition of 1-ethoxy-1-(trimethylsilyloxy)cyclopropane to aldehydes. The reactions proceed with ee's of up to 72% and are effective with a range of aldehyde substrates. The reactions show greatly improved enantioselectivity when compared to those catalyzed by titanium(IV)
Enantioselective Ketone Hydroacylation Using Noyori’s Transfer Hydrogenation Catalyst
作者:Stephen K. Murphy、Vy M. Dong
DOI:10.1021/ja4021974
日期:2013.4.17
An enantioselectiveketone hydroacylation enables the direct preparation of lactones from keto alcohols. The alcohol is oxidized in situ to an aldehyde, obviating the need to prepare sensitive keto aldehyde substrates. Noyori's asymmetric transferhydrogenationcatalyst was applied to address challenges of reactivity, chemoselectivity, and enantioselectivity.