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Updated: Jul 5, 2025

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Photochemical Radical Bicyclization of 1,5-Enynes: Divergent Synthesis of Fluorenes and Azepinones
Babasaheb Sopan Gore1, Chun-Cheng Chen1, Ping-Yu Lin1
1Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, No. 100, Shih-Chuan First Rd, Sanmin District, Kaohsiung City 807, Taiwan.
Abstract:
A dual nickel- and iridium-photocatalyzed radical cascade bicyclization reaction for the synthesis of highly complex molecular structures in an atom- and step-economic manner has been described. A series of radical precursors are utilized for the divergent synthesis of diversely substituted fluorenes and indenoazepinones bearing quaternary carbons by using cascade cyclization reactions of 1,5-enynes. This reaction is characterized by its mild conditions, broad substrate scope, excellent selectivity, and satisfactory yield including facile scale-up synthesis.
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