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Cobalt(II)-Catalyzed Decarboxylative C-H Activation/Annulation Cascades: Regioselective Access to Isoquinolones and

Xin-Qi Hao¹, Cong Du¹, Xinju Zhu¹

¹College of Chemistry and Molecular Engineering, Zhengzhou University , Zhengzhou 450001, P. R. China.

Organic Letters

|July 21, 2016

Abstract:

A new cobalt(II)-catalyzed decarboxylative C-H activation/annulation of benzamides and alkynyl carboxylic acids has been described. Alkynyl carboxylic acids were first employed as the coupling partners using inexpensive Co(OAc)2·4H2O as the catalyst. This method enables a switchable cyclization to isoquinolones and isoindolinones with excellent selectivity. Moreover, a catalytic amount of Ag2O was adopted as co-catalyst and O2 (from air) as a terminal oxidant for the preparation of isoquinolones.

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