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Published on: April 22, 2016
Visible-Light-Driven Photoredox-Catalyzed [4 + 2] Annulation of Unsaturated α-Bromocarbonyls with α-Substituted
Shijing Tu1,2, Xinyu Zhong2, Ting Zou3
1Ph.D. Degree Program in Pharmacy, Faculty of Pharmacy, Chiang Mai University, Under the CMU Presidential Scholarship, Chiang Mai 50200, Thailand.
Abstract:
Cyclohexenes are ubiquitous structural motifs in pharmaceuticals and natural products, yet their efficient and sustainable synthesis from simple precursors remains a challenge. Herein, we report a visible-light-driven photoredox-catalyzed intermolecular [4 + 2] annulation that enables rapid, regioselective access to multisubstituted cyclohexenes from readily accessible unsaturated α-bromocarbonyls with α-substituted styrenes. The mild, operationally simple conditions accommodate diverse functional groups and enable gram-scale synthesis, versatile product elaboration, and access to a complex bicyclo[2.2.2]octene framework.
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