<i>C</i><sub>2</sub>-Symmetric Enantiopure Ethanotethered Bis(α,β-butenolides) as Templates for Asymmetric Synthesis. Application to the Synthesis of (+)-Grandisol<sup>1</sup>
作者:Pedro de March、Marta Figueredo、Josep Font、Javier Raya、Angel Alvarez-Larena、Juan F. Piniella
DOI:10.1021/jo026705w
日期:2003.3.1
Starting from D-mannitol, we have prepared several C(2)-symmetric ethanotethered bis(alpha,beta-butenolides) and studied their [2+2] photocycloaddition reaction with ethylene. The protective groups of the central diol unit have a noticeable influence on the facial selectivity of the cycloaddition, the bis(trimethylsilyloxy) derivatives showing the highest diastereoselectivity. A theoretical conformational