Steric Factors in the Single-Electron Transfer Carbolithiation and Transannular Reduction of 6,12-Diphenyldibenzo[<i>b</i>,<i>f</i>][1,5]diazocine by Organolithium Reagents
作者:John J. Eisch、Kun Yu、Arnold L. Rheingold
DOI:10.1002/ejoc.201301181
日期:2014.2
products were observed in such hydrolyzed reactions: (1) exo-1,2-addition to a C=N bond by C6H5CH2Li, H2C=CHCH2MgCl, and CH3Li, as established by spectral and XRD data; (2) 1,4-addition to the ortho-phenyl carbon Co=C-C=N linkage by phenyllithium with the subsequent elimination of LiH; and (3) 1,4-addition, as in type 2, by n-butyllithium but without the elimination of LiH. The foregoing modes of reactivity
褶皱三环杂环 6,12-二苯基二苯并[b,f][1,5]重氮辛是一种揭示单电子转移 (SET) 反应的新型探针,这里用作研究亚胺和这种 R-Li 添加的立体化学、区域化学和电子性质(极性或 SET)。研究了以下有机锂试剂(主要在 THF 中)对重氮辛的化学行为:苄基-、甲基-、苯基-、正丁基-和苯基乙炔基锂,以及反应性烯丙基氯化镁和典型的叔丁基氯化镁. 唯一未能实现碳金属化或环环还原重氮辛的试剂是苯乙炔基锂。叔丁基格氏试剂不能进行碳金属化,但可以通过光催化还原重氮辛。其他五种有机金属化合物既产生重氮辛的碳金属化,又产生了不同比例的跨环 SET 还原成 4b,9b-diphenyl-4b,5,9b,10-四氢吲哚[3,2-b]吲哚(“吲哚吲哚”) . 在此类水解反应中观察到三种类型的碳金属化产物:(1)通过光谱和 XRD 数据确定,C6H5CH2Li、H2C=CHCH2MgCl 和 CH3Li