New efficient synthesis of 2,3,4-trisubstituted 3,4-dihydroquinazolines by a Ugi 4CC/Staudinger/aza-Wittig sequence
作者:Ying Zhong、Long Wang、Ming-Wu Ding
DOI:10.1016/j.tet.2011.03.056
日期:2011.5
A series of 2,3,4-trisubstituted 3,4-dihydroquinazoline 3 was prepared by intramolecular aza-Wittig reaction of amide carbonyl groups with methyldiphenyl iminophosphorane, which was obtained from a Ugi 4CC/Staudinger sequence. Further intramolecular Heck reaction of 3d′–g′ in the presence of catalytic amount of Pd(OAc)2 gave 6,12-dihydroindolo[2,1-b]quinazolines 4a–d in good yields.
通过酰胺羰基与Ugi 4CC / Staudinger序列获得的甲基二苯基亚氨基正膦的分子内氮杂-Wittig反应,制备了一系列2,3,4-三取代的3,4-二氢喹唑啉3。的进一步分子内Heck反应的3d ' -克'中的Pd(OAC)的催化量存在2得到6,12-二氢吲哚并[2,1- b ]喹唑啉4A - d以良好的收率。