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Updated: May 24, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
A second monoclinic polymorph of
Abstract:
The asymmetric unit of the title compound, [NiCl(2)(C(19)H(9)F(6)N(3))], contains one half-mol-ecule residing on a crystallographic twofold rotation axis. The title compound crystallizes in space group C2/c while the previously reported polymorph was reported in P2(1)/c [Baldovino-Pantaleón et al. (2006 ▶). Adv. Synth. Catal.348, 236-242]. The Ni(2+) ion exhibits a penta-coordinate distorted trigonal-bipyramidal NiCl(2)N(3) geometry, with two Cl atoms in the equatorial plane. In the crystal, mol-ecules are linked by inter-molecular C-F⋯π [F⋯centroid = 2.9676 (14) Å] inter-actions.
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