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Published on: May 21, 2019
Visible-Light Photocatalytic Nucleophilic Addition of 4-Pyridylphosphonium Salts to CO2 and Carbonyl Compounds
Wenwen Cui1, Bin Li1, Baiquan Wang1,2
1State Key Laboratory of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, Tianjin 300071, People's Republic of China.
Abstract:
A visible-light photocatalytic nucleophilic addition of 4-pyridylphosphonium salts to CO2 and carbonyl compounds is reported. The reaction has mild reaction conditions, good functional group tolerance, and a wide range of substrates. Mechanistic studies show that the reaction may occur through the pyridylphosphonium salt radical anion, pyridyl radical, and pyridyl anion intermediates. By combination with C4-H phosphination, this method can be applied to the late-stage C-H functionalization of drugs containing a pyridine unit.
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