4-fused skeleton. Aldehyde serves as a key to start the whole process, including 1,6-hydride transfer enabled δ-C(sp3)–H activation of the secondary amine. The challenges of construction of medium-sized rings are addressed via hydride transfer chemistry.
<i>tert</i>-Amino Effect-Promoted Rearrangement of Aryl Isothiocyanate: A Versatile Approach to Benzimidazothiazepines and Benzimidazothioethers
作者:Xinyu Geng、Siyuan Liu、Wenyao Wang、Jingping Qu、Baomin Wang
DOI:10.1021/acs.joc.0c01806
日期:2020.10.2
A general and practical approach to benzimidazothiazepine and benzimidazothioether derivatives via an intramolecular nucleophilic addition/ring expansion rearrangement of aryl isothiocyanates promoted by the tert-amino effect has been developed. This reaction is catalyzed by low-cost camphorsulfonic acid and tolerates a broad substrate scope with complete atom economy. Structurally intriguing benzimidazothiazepine