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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Decarboxylative [4+2] annulation of arylglyoxylic acids with internal alkynes using the anodic ruthenium catalysis
Mu-Jia Luo1, Ting-Ting Zhang2, Fang-Jun Cai2
1State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, China. delianghe@hnu.edu.cn jhli@hnu.edu.cn and Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China.
Abstract:
A new electrochemical decarboxylative [4+2] annulation of arylglyoxylic acids with internal alkynes involving C-H functionalization by means of a cooperative anode and ruthenium catalysis is presented. This reaction represents a mechanistically novel strategy as an ideal supplement to the decarboxylative [4+2] annulation methodology by employing an electrooxidative process to avoid the use of an additional external oxidizing reagent and utilizing H2O as the carboxyl oxygen atom source to be engaged in the synthesis of 1H-isochromen-1-ones.
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