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Updated: Jun 26, 2025

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Room-Temperature Cascade Electrophilic Addition/Cyclization/Oxidation Reactions: Divergent Selective Synthesis of
Guodong Shen1, Zhanjun Li1,2, Lingyu Zhao1
1School of Chemistry and Chemical Engineering, Liaocheng University, 1 Hunan Avenue, Liaocheng, 252000, Shandong, P. R. China.
Abstract:
The room temperature metal-free cascade electrophilic addition/cyclization/oxidation reactions of (3-phenoxyprop-1-yn-1-yl)benzenes to divergently synthesize various brominated benzopyran derivatives (3-bromo-2H-chromenes, 3-bromo-2H-chromen-2-ols and 3-bromo coumarins) by tuning the amount of Br2 and H2O have been developed. The method exhibited high selectivity, mild reaction conditions, broad substrate scope, high efficiency, and the applicability for derivatization of the brominated products. The importance of the strategies provides a great advantage for selective synthesis of brominated benzopyran derivatives.
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