Lewis Base Catalyzed [4+2] Annulation of Electron-Deficient Chromone-Derived Heterodienes and Acetylenes
作者:Heiko Dückert、Vivek Khedkar、Herbert Waldmann、Kamal Kumar
DOI:10.1002/chem.201003572
日期:2011.4.26
Lewis base catalyzed [4+2] annulation reactions between electron‐deficient chromone oxa‐ and azadienes and acetylene carboxylates provide tricyclic benzopyrones inspired by natural products. An asymmetric synthesis of the tricyclic benzopyrones was developed by using modified cinchona alkaloids as enantiodifferentiating Lewis base catalysts.
电子不足的色酮,氧杂氮杂和氮杂二烯与乙炔羧酸盐之间的Lewis碱催化的[4 + 2]环化反应提供了受自然产物启发的三环苯并吡喃酮。三环苯并吡喃酮的不对称合成是通过使用改性金鸡纳生物碱作为对映体易差的路易斯碱催化剂而开发的。