Cobalt-catalyzed chemoselective dehydrogenation through radical translocation under visible light. Issue 26 (23rd June 2022)

• Record Type: Journal Article
• Authors: Yu, Wan-Lei; Ren, Zi-Gang; Ma, Ke-Xing; Yang, Hui-Qing; Yang, Jun-Jie; Zheng, Haixue; Wu, Wangsuo; Xu, Peng-Fei
• Is Part Of: Chemical science. Volume 13:Issue 26(2022)
• Page Start: 7947
• Page End: 7954
• Publication Date: 2022-06-23
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d2sc02291e
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : The dehydrogenative reactions proceeded through selective 1, n -hydrogen atom transfer ( n = 5–7) for remote C–H activation by cobaloxime catalysis. Abstract : The transformations that allow the direct removal of hydrogen from their corresponding saturated counterparts by the dehydrogenative strategy are a dream reaction that has remained largely underexplored. In this report, a straightforward and robust cobaloxime-catalyzed photochemical dehydrogenation strategy via intramolecular HAT is described for the first time. The reaction proceeds through an intramolecular radical translocation followed by the cobalt assisted dehydrogenation without needing any other external photosensitizers, noble-metals or oxidants. With this approach, a series of valuable unsaturated compounds such as α, β-unsaturated amides, enamides and allylic and homoallylic sulfonamides were obtained in moderate to excellent yields with good chemo- and regioselectivities, and the synthetic versatility was demonstrated by a range of transformations. And mechanistic studies of the method are discussed.