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Updated: Jan 12, 2026

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
XAT-Generated Azirinyl Radicals in Selective Giese-Type Alkylation of 2H-Azirines
Anastasiya V Agafonova1, Julia I Pavlenko1, Timur O Zanakhov1
1St. Petersburg State University, Institute of Chemistry, 7/9 Universitetskaya nab., St. Petersburg 199034, Russia.
Abstract:
We report a radical strategy for direct C2-alkylation of 2H-azirines via generation of elusive 2H-azirinyl radicals. These highly reactive intermediates are accessed under mild halogen-atom transfer conditions from readily available 2-haloazirines. The resulting cyclic radicals undergo regioselective Giese-type additions to electron-deficient alkenes, retaining the azirine ring. Mechanistic studies, including spin-trapping and DFT analysis, support a free radical pathway. The adducts undergo base-promoted ring expansion to yield 6-aminopyridines, underscoring this platform's synthetic utility.
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