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Updated: Jan 9, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Geometry-Controlled Synthesis of Pyrido/Pyrrolo-isoindolones via MHAT Radical Cyclization of Carbethoxy Methylene
Santosh J Gharpure1, Rupali S Chavan1, Kaushik C Pansuriya1
1Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
Abstract:
A geometry-dependent intramolecular MHAT (metal-hydride hydrogen atom transfer) cyclization of olefins using carbethoxy methylene isoindolone as a radical acceptor has been developed for the synthesis of pyrroloisoindolone and pyridoisoindolone derivatives. The regioselectivity is dictated by the geometry of the substrate. While E-carbethoxy methylene isoindolones undergo selective 6-endo-trig HAT cyclization to afford pyrido[2,1-a]isoindolones, the corresponding Z-isomers favor 5-exo-trig cyclization, producing pyrrolo[2,1-a]isoindolones. The mechanistic understanding was further substantiated by control experiments.
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