Radical-Mediated 5-<i>E</i><i>xo</i>-<i>Trig</i> Cyclizations of 3-Silylhepta-1,6-dienes
作者:Philippe James、Kurt Schenk、Yannick Landais
DOI:10.1021/jo060024+
日期:2006.4.1
radical mediated 5-exo-trigcyclization of 3-silylheptadienyl systems 3a−d has been studied. At low temperature, the reaction of the sulfonyl radical occurs regioselectively at the allylsilane terminus, while a reversal of regioselectivity is observed at 80 °C. This general trend has been rationalized on the basis of polar effects and radical stabilization. Thiyl-mediated radical cyclization of dienes 3a