Spontaneous formation of tricyclic lactones following the Castagnoli–Cushman reaction
作者:Liliia Usmanova、Olga Bakulina、Dmitry Dar’in、Mikhail Krasavin
DOI:10.1007/s10593-017-2076-y
日期:2017.4
carboxylic acids. However, the latter underwent a spontaneous intramolecular reaction of the carboxylic functionality onto the labile nearby 2-chloropyridine moiety to give the respective tricyclic lactones in 17–23% yield, along with 41–68% yield of the uncyclized trans-configured products (isolated as methyl esters).
如所预期的,在110°C下于DMF中进行了1个小时内,由2-氯吡啶-3-甲醛衍生的亚胺与环酐(4-(甲基磺酰基)-吗啉-2,6-二酮)的Castagnoli-Cushman反应导致了的混合物的反式与顺式-型羧酸。然而,后者后行的羧酸官能到附近的2-氯吡啶部分上的不稳定的自发分子内反应,得到17-23%产率的相应三环内酯,与未环化的41-68%的产率沿反式配置的产品(隔绝作为甲酯)。