1. β-Selective Aroylation of Activated Alkenes by Photoredox Catalysis.
- Author
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Lei Z, Banerjee A, Kusevska E, Rizzo E, Liu P, and Ngai MY
- Subjects
- Catalysis, Oxidation-Reduction, Alkenes chemistry, Benzene Derivatives chemistry, Chlorides chemistry, Photochemical Processes
- Abstract
Late-stage synthesis of α,β-unsaturated aryl ketones remains an unmet challenge in organic synthesis. Reported herein is a photocatalytic non-chain-radical aroyl chlorination of alkenes by a 1,3-chlorine atom shift to form β-chloroketones as masked enones that liberate the desired enones upon workup. This strategy suppresses side reactions of the enone products. The reaction tolerates a wide array of functional groups and complex molecules including derivatives of peptides, sugars, natural products, nucleosides, and marketed drugs. Notably, addition of 2,6-di-tert-butyl-4-methyl-pyridine enhances the quantum yield and efficiency of the cross-coupling reaction. Experimental and computational studies suggest a mechanism involving PCET, formation and reaction of an α-chloro-α-hydroxy benzyl radical, and 1,3-chlorine atom shift., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2019
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