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Updated: Aug 6, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Violet-light-induced ring expansion of 2-aryl-1,3-indandiones with chlorodiazirines toward 1,4-naphthoquinones
Bao-Jie Wang1, Xinyu Zhang1, Huimin Liang1
1State Key Laboratory Base of Eco-Chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology Qingdao 266042 P. R. China zhang_linbao@126.com.
Abstract:
1,4-Naphthoquinones are widely used in medicine and materials, but noble metal catalysts and harsh conditions limit their synthesis. We report a violet-light-induced skeletal editing strategy that enables ring-expansion of 2-aryl-1,3-indandiones via single-carbon insertion using chlorodiazirines as carbene precursors. This protocol proceeds without metal catalysts or ligands, featuring broad substrate scope, excellent selectivity, high efficiency under mild conditions, and moderate to good yields. Mechanistic studies indicate that the reaction proceeds via carbene [2 + 1] cycloaddition, followed by ring expansion.
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