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Updated: Feb 22, 2026

Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Synthesis of highly substituted benzene ring systems through three-component coupling of enyne imines, Fischer
Bishnu Dhakal1, Lalith S R Gamage1, Yanshi Zhang1
1Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM 88003 USA.
Abstract:
Three-component coupling of Fischer carbene complexes, enyne aldehyde hydrazones, and electron-deficient alkynes leads to simple benzoate derivatives in a process involving the formation of an N-aminopyrrole derivative, Diels-Alder reaction, and nitrene extrusion. The products are readily converted into isoquinolones through reaction with primary amines. The reaction proceeds best with highly substituted and electron-rich pyrroles even though these are the sterically least favorable substrates, and this reactivity trend is supported by a computational study.
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