Functionalized Cyclobutenes via Multicomponent Thermal [2 + 2] Cycloaddition Reactions
作者:Helen M. Sheldrake、Timothy W. Wallace、Craig P. Wilson
DOI:10.1021/ol051675f
日期:2005.9.1
[reaction: see text] Enamine [2 + 2] cycloadditions can be achieved in useful yields simply by stirring a mixture of an aldehyde, diethylamine, a dialkyl fumarate, and potassium carbonate in acetonitrile at 25 degrees C, conditions that are compatible with the presence of a potential leaving group on the beta-position of the intermediate enamine. Methylation and elimination of the product cyclobutanes
[反应:见正文]烯胺[2 + 2]的环加成反应可通过在25°C下在与乙腈相容的条件下搅拌乙醛,二乙胺,富马酸二烷基酯和碳酸钾在乙腈中的混合物来实现在中间体烯胺的β位上存在潜在的离去基团。甲基化和产物环丁烷的消除完成了温和的非光化学路线,从而实现了官能化的环丁烯。