Bromide-promoted cascade annulation of isocyanobiaryls with aldehydes through photoredox catalysis.

Org Biomol Chem

Key Laboratory for Green Organic Synthesis and Application of Hunan Province, Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China.

Published: January 2025

Herein, we report a cascade annulation of readily available isocyanobiaryls with simple aldehydes photoredox catalysis, providing a straightforward approach towards valuable 6-hydroxyalkylated phenanthridines. Mechanistic studies indicated the generation of a key acyl radical from aldehydes by hydrogen atom abstraction with a bromine radical. This protocol exhibits exceptional chemoselectivity, excellent tolerance of various functional groups and mild reaction conditions. Its synthetic utility was demonstrated by a gram-scale reaction and various facile manipulations of the free hydroxyl group to furnish diverse phenanthridine derivatives.

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http://dx.doi.org/10.1039/d4ob02085eDOI Listing

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