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Updated: Jun 5, 2025

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Metal-free radical cascade cyclization/haloazidation of enynones to access functionalized 1-indanones
Hua-Feng Yan1, Xiao Zou2, Jian-Qiang Wang1
1College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China. guocheng@njtech.edu.cn.
Abstract:
A novel three-component radical cyclization/haloazidation of enynones, employing TMSN3 as the azide source and NIS (NBS or NCS) as the halogen source, has been developed under metal-free conditions for the efficient synthesis of various 1-indanones with moderate yields and acceptable Z/E ratio. The reaction progresses through a sequence involving radical addition, 5-exo-dig cyclization, and radical coupling, ultimately resulting in the formation of three new chemical bonds and a new ring in a single step. The synthetic benefits of this method have been proven by large-scale experiments and late-stage modification.
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