학술논문
Switching of Product's Chirality in Diastereodifferentiating [2+2] Photocycloaddition of (E)- versus (Z)-Stilbene to Chiral Fumarate upon Direct and Charge-Transfer-Band Excitation
Document Type
Article
Source
Organic Letters; April 2006, Vol. 8 Issue: 9 p1909-1912, 4p
Subject
Language
ISSN
15237060; 15237052
Abstract
Diastereodifferentiating [2+2] photocycloadditions of (E)- and (Z)-stilbenes to bis((R)-1-methylpropyl) fumarate were performed through the direct excitation of stilbenes and the selective excitation of the charge-transfer (CT) complex at various temperatures. The geometrical isomers of stilbene afforded the opposite diastereomers of μ-truxinate in both excitation modes, with a dramatic decrease in the product's diastereoselectivity upon prolonged irradiations.