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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
Photochemical Formal [4 + 2] Cycloaddition of α-Bromo Phenylsulfones and Acetophenones with Alkenes
Zhengsen Yu1, Yanhui Gou1, Yuting He1
1College of Life Sciences, Hebei Agricultural University, Baoding 071000, China.
Abstract:
Benzocycles are the predominant skeletons in medicinal chemistry. Herein, we report a modular and practical [4 + 2] cycloaddition reaction for the photochemical synthesis of benzocyclic sulfones/ketones via sequential alkylation and arylation across an olefinic double bond. This scalable approach is compatible with the direct cyclization of α-bromo phenylsulfones or acetophenones with various alkenes, which can be expected to rapidly convert abundant alkene feedstocks into medically relevant molecules and the late-stage functionalization of pharmacologically related substrates.
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