Related Experiment Video
Updated: Jun 1, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
1,2,4,5-Tetra-fluoro-3,6-diiodo-benzene-2,3-bis-(pyridin-2-yl)pyrazine (1/1)
Abstract:
The components of the title 1:1 co-crystal, C(14)H(10)N(4)·C(6)F(4)I(2), are connected via an N⋯I [2.959 (4) Å] halogen bond, in which the N atom is part of the relatively electron-rich pyrazine ring. The C(6)F(4)I(2) mol-ecule is almost planar [r.m.s. deviation = 0.038 Å] but there are significant twists in the pyrazine derivative, as seen in the dihedral angles [31.3 (2) and 54.6 (2)°] formed between the pendant pyridyl rings and the central pyrazine ring. The bimolecular aggregates are sustained in the crystal by C-H⋯F and π-π inter-actions [ring centroid(pyrid-yl)-ring centroid(benzene) = 3.678 (3) Å].
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