温度对氮杂环卡宾催化下α-溴代烯醛与烯胺酮的[3+3]环化反应影响

Effect of Temperature on N-Heterocyclic Carbene-Catalyzed [3+3] Annulation of α-Bromoenal with Enaminone

氮杂环卡宾(NHC)催化下α-溴代烯醛和烯胺酮的[3+3]环化反应的区域选择性受温度控制.在35℃时,该反应能够区域专一性地给出稠合吡喃酮衍生物,而不是文献报道的喹啉酮类化合物.该方法反应条件温和、底物范围广、产率高、操作简便,为吡喃酮骨架的高效构建提供了新思路.

The regioselectivity of N-heterocyclic carbene(NHC)-catalyzed[3+3]annulation ofα-bromoenal with enaminone is dependent on the temperature.The reactions performed at 35℃could regiospecifically give the derivatives of fused pyranone instead of previously reported quinolones,which provided a new shortcut to pyranone with mild reaction condition,broad substrate scope,high yields and operational simplicity.