Divergent [2 + ] Heteroannulation of β-CF-1,3-enynes with Alkyl Azides via Hydrogen Atom Transfer and Radical Substitution.

Org Lett

Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China.

Published: February 2024

A copper-promoted divergent intermolecular [2 + ] heteroannulation of β-CF-1,3-enynes with alkyl azides via alkyl radical-driven HAT and radical substitution (C-C bond formation) to form four- to ten-membered saturated -heterocycles is developed. This method enables the aryl-induced or kinetically controlled site selective functionalization of the remote C(sp)-H bonds at positions 2, 3, 4, 5, 6, 7, or 8 toward the nitrogen atom through triplet nitrene formation, radical addition across the C═C bond, HAT and radical substitution cascades, and features a broad substrate scope, excellent site selectivity, and facile late-stage derivatization of bioactive molecules. Initial deuterium-labeling and control experiments shed light on the reaction mechanism via nitrene formation and HAT.

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http://dx.doi.org/10.1021/acs.orglett.3c04041DOI Listing

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