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Updated: Jun 2, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Complete solid state photoisomerization of bis(dipyrazolylstyrylpyridine)iron(II) to change magnetic properties
Yuta Hasegawa1, Kazuhiro Takahashi, Shoko Kume
1Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Tokyo, 113-0033, Japan.
Abstract:
Iron(II) complexes of Z- and E-2,6-di(1H-pyrazol-1-yl)-4-styrylpyridine (Z-2 and E-2, respectively) exhibited visible light photoisomerization from Z-2 to E-2, both in solution and in solid phases. Z-2 occupied the high-spin state over the full temperature range examined, whereas E-2 displayed a spin crossover phenomenon between 100 K and 300 K.
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