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Updated: Jun 12, 2025

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Pyrrolizinofluorene-embedded dithiacalixcorrole(1.0.1.1)s
Pooja Varak1, Mangalampalli Ravikanth1
1Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India. ravikanth@chem.iitb.ac.in.
Abstract:
An unprecedented synthesis of pyrrolizinofluorene moiety embedded dithiacalixcorrole(1.0.1.1)s via [3 + 2] condensation of fluorene-based tripyrrane and appropriate bithiophene diol under TFA-catalyzed conditions is reported. Single crystal X-ray structural analysis revealed that the fluorene unit was inverted and involved in the intramolecular C-N bond formation, resulting in the generation of an unusual pyrrolizinofluorene moiety as part of the dithiacalixcorrole(1.0.1.1) framework. These macrocycles exhibit strong absorption in the UV-visible region and electrochemical studies revealed their electron-rich nature.
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