Enantioselective vinylogous aldol reaction of Chan’s diene catalyzed by hydrogen-bonding
摘要:
Hydrogen-bonding activation of aromatic aldehydes by a TADDOL-derivative promotes the vinylogous aldol reaction of Chan's diene in moderate efficiency and enantioselectivity. Electron-poor aromatic aldehydes show an enhanced reactivity and a competing asymmetric hetero-Diels-Alder reaction takes place in comparable (or higher) yields and enantiomeric excesses. (c) 2006 Elsevier Ltd. All rights reserved.