Silicon-DirectedNazarov Reactions II. Preparation and Cyclization of ?-Silyl-substituted Divinyl Ketones
作者:Todd K. Jones、Scott E. Denmark
DOI:10.1002/hlca.19830660802
日期:1983.12.14
Two general methods for the preparation of β-silyl-substituted divinyl ketones have been developed starting from either α, β-unsaturated aldehydes or simple ketones. Anhydrous FeCl3 induces the cyclization to cyclopentenones under mild conditions and in good yields with predictable and complete control over the position of the double bond in the five-membered ring. The observed effects of substituents
从α,β-不饱和醛或简单的酮开始,已经开发了两种制备β-甲硅烷基取代的二乙烯基酮的通用方法。无水FeCl 3在温和条件下以高收率诱导环化成环戊烯酮,并且可预测和完全控制五元环中双键的位置。观察到的取代基对速率的影响可以通过速率决定性阳离子电环化来解释。已显示甲硅烷基取代会阻碍反应。