An unprecedented reductive (3 + 2) annulation of both symmetrical and unsymmetrical benzils with pyrylium salts mediated by P(NMe2)3 is described, leading to facile and stereoselective access to the challenging cis-chalcones decorated by various substituted furyl rings under mild conditions. Rather than the extensively studied C1 synthons, the Kukhtin–Ramirez adducts derived from benzils serve as the
描述了P(NMe2)3介导的
吡咯盐对对称和不对称苄基化合物的空前还原(3 + 2)环化反应,可在温和条件下方便且立体选择性地进入由各种取代的
呋喃基环修饰的具有挑战性的顺式
查耳酮。取代
苯甲醚的库克汀-拉米雷斯加合物,而不是经过广泛研究的C1合成子,在这种(3 + 2)环空中,与2,6-二取代的
吡啶离子的2,3-双键一起用作未充分开发的C3合成子。