Elemental Sulfur-Mediated Decarboxylative Redox Cyclization Reaction: Copper-Catalyzed Synthesis of 2-Substituted BenzothiazolesWe thank the National High Technology Research and Development Program of China (863 Program 2014AA022100), Six Talent Peaks Project in Jiangsu Province (No. 2015-SWYY-016) and Graduate Student Innovation Project in Jiangsu Province (Grant No. SJCX17_0287) for supporting this research.
Received: 30 July 2017
Accepted after revision: 03 September 2017
27 September 2017 (eFirst)
A S8-mediated directed decarboxylative redox-cyclization strategy for the synthesis of 2-substituted benzothiazoles from o-iodoanilines, arylacetic acids, and elemental sulfur catalyzed by cheap copper metal has been developed. This reaction is operationally simple, ligand-free, compatible with a wide range of functional groups, and provides the desired products in good to excellent yields. In addition, a gram-scale experiment was carried out to furnish PMX 610, an antitumor drug.