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Updated: Mar 28, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Straightforward synthesis of tetraalkynylpyrazines and their photophysical properties
Andranik Petrosyan1, Peter Ehlers, Annette-E Surkus
1Institut für Chemie, Universität Rostock, Albert Einstein Str. 3a, 18059 Rostock, Germany. peter.langer@uni-rostock.de.
Abstract:
Tetrafold Sonogashira reactions of tetrachloropyrazine were investigated to provide a one-step synthesis of various tetraalkynylpyrazines. The reaction conditions were thoroughly optimized using modern catalysts and ligands, and products were generally isolated in good to excellent yields. Furthermore, photophysical and electrochemical properties of selected compounds were studied and compared with those of previously reported tetraalkynylpyridines and benzenes. As a matter of fact, tetraalkynylpyrazines proved to show very promising fluorescence properties due to very high quantum yields reaching up to 0.85.
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