The cyclisation of benzonitrile 3,3-diarylallyl ylides to give 3H-2-benzazepines: Substituent directive effects and mechanism
作者:Paul W. Groundwater、John T. Sharp
DOI:10.1016/s0040-4039(00)96047-7
日期:1987.1
reaction of imidoyl chlorides with base, cyclised by 1,7-ring closure to give 3H-2-benzazepines (9), in contrast to analogous diazo-compounds (1) which prefer 1,5-electrocyclisation. Asymmetrically placed substituents (R in 14b) favour substitution at the (2′) position irrespective of their polar electronic effects. Deuterium labelling studies have shown that the cyclisation step is irreversible for nitrile
与亚胺基重氮化合物(1)相比,亚甲酰氯(7)是由亚氨酰氯与碱反应生成的,被1,7环闭合环化,得到3H-2-苯并ze庚因(9)。 ,5-电环化。不对称放置的取代基(14b中的R)有利于在(2')位置进行取代,无论其极性电子效应如何。氘标记研究表明,环化步骤对于腈(14b)是不可逆的,而对于重氮化合物(14a)是可逆的。