Visible-light-induced aerobic oxidative desulfurization of 2-mercaptobenzimidazoles via a sulfinyl radical. Issue 17 (13th August 2020)

• Record Type: Journal Article
• Authors: Fu, Mei; Ji, Xiaochen; Li, Yongtong; Deng, Guo-Jun; Huang, Huawen
• Is Part Of: Green chemistry. Volume 22:Issue 17(2020)
• Page Start: 5594
• Page End: 5598
• Publication Date: 2020-08-13
• Subjects: Environmental chemistry -- Industrial applications -- Periodicals; Environmental management -- Periodicals; 660
• DOI: 10.1039/d0gc02269a
• Languages: English
• ISSNs: 1463-9262

Abstract

Abstract : A mild transition-metal-free non-toxic aerobic photoredox system was found to enable highly efficient desulfurization of 2-mercaptobenzimidazoles. Abstract : A mild transition-metal-free non-toxic aerobic photoredox system was found to enable highly efficient desulfurization of 2-mercaptobenzimidazoles. This viable catalytic system includes Rose Bengal in a low catalyst loading as a photosensitizer and cheap, non-toxic NaCl in a catalytic amount as an additive, combined with an oxygen atmosphere. This protocol provides an important alternative access to a broad range of benzimidazole and deuterated benzimidazole products in generally high yields with good tolerance of various synthetically and pharmaceutically useful functionalities. The mechanistic studies reveal that both single electron transfer and energy transfer probably occur in the initial step and a sulfinyl radical intermediate is involved in the key desulfurization process.