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Updated: Apr 18, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Fused corrole dimers interconvert between nonaromatic and aromatic states through two-electron redox reactions
Shota Ooi1, Takayuki Tanaka, Kyu Hyung Park
1Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan).
Abstract:
A singly linked corrole dimer was synthesized by condensation of a dipyrromethane-1-carbinol with 1,1,2,2-tetrapyrroethane. Oxidation of the dimer gave doubly linked corrole dimers 9 and 10 as the first examples of fused corrole dimers involving a meso-meso linkage. Dimers 9 and 10 exhibit characteristic (1)H NMR spectra, absorption spectra, excited-state dynamics, and two-photon absorption (TPA) values, which indicate the nonaromatic nature of 9 and the aromatic nature of 10. Interestingly, 9 is fairly stable despite its unusual 2H-corrole structure, which has been ascribed to the presence of two direct connections between the individual corrole units.
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