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Updated: May 3, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
A core-expanded subphthalocyanine analogue with a significantly distorted conjugated surface and unprecedented
Soji Shimizu1, Shota Nakano, Ayaka Kojima
1Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578 (Japan). ssoji@m.tohoku.ac.jp.
Abstract:
The introduction of a seven-membered-ring unit in the place of a five-membered-ring unit in the structure of subphthalocyanine resulted in significant distortion of the bowl-shaped structure of the conjugated molecule as well as the following unprecedented properties: the preferential formation of the axially fluoro substituted species, the fluttering-dynamic-motion-induced rapid exchange of P and M enantiomers, markedly split Q-band absorption, and a clear difference in the ring-current effects arising from the convex and concave surfaces.
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