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Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Access to gem-Dibromoenones Enabled by Carbon-Centered Radical Addition to Terminal Alkynes in Water Solution
Xianghua Zeng1, Yuhai Xu1, Jiawei Liu1
1College of Biological, Chemical Science and Engineering, Jiaxing University, 118 Jiahang Road, Jiaxing 314001, P.R. China.
Abstract:
We herein report a novel and more practical approach to prepare gem-dibromoenones from terminal alkynes, tetrabromomethane (CBr4), and water in a single step. Mechanistic studies reveal that the generation of a tribromomethyl radical with the assistance of a persulfate salt (K2S2O8) is essential to this transformation. The reaction features readily available chemicals, a broad substrate scope, a green solvent, and mild reaction conditions, providing an efficient alternative for construction of halogen-substituted enones.
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