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Updated: Sep 10, 2025

Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes
Published on: April 1, 2013
Visible-Light-Induced Intramolecular Dehydrogenative Cyclization of o-Aryl Benzaldehydes
Yongkai Zhao1, Jipeng Qi1, Wei-Yu Shi1
1College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, P. R. China.
Abstract:
A visible-light-induced dehydrogenative cyclization of o-aryl benzaldehydes has been developed by using bench-stable N-aminopyridinium salt as both a HAT reagent and a mild oxidant, which affords a wide range of fluorenones with diverse substitution patterns in moderate to excellent yields. Furthermore, this protocol is applicable to the de novo synthesis of the natural product Nobilone. Mechanism investigation supports a photoinduced homocleavage of N-aminopyridinium salt and a radical chain process.
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