Crystal structure and Hirshfeld analysis of trans -bis-(5-fluoro-indoline-2,3-dione 3-oximato-κ 2 O 2 , N 3 )- trans -bis-(pyridine-κ N )copper(II).

The reaction in methanol of Cu ^II acetate monohydrate with 5-fluoro-isatin 3-oxime deprotonated with KOH in a 1:2 molar ratio and recrystallization from pyridine yielded the title compound, [Cu(C ₈ H ₄ FN ₂ O ₂ ) ₂ (C ₅ H ₅ N) ₂ ]. In the centrosymmetric complex, the anionic form of the isatin oxime acts as a κ ² N , O donor, building five-membered metallarings. The Cu ^II cation is sixfold coordinated in a slightly distorted octa-hedral environment by two trans , equatorial, anionic isatin derivatives and two trans pyridine ligands in axial positions. The complexes are linked by hydrogen bonding into a three-dimensional network, which is also stabilized by π-π stacking inter-actions [centroid-to-centroid distance = 3.7352 (9) Å] and C-H⋯π contacts. The Hirshfeld surface analysis indicates that the major contributions for the crystal packing are H⋯H (31.80%), H⋯C (24.30%), H⋯O (15.20%) and H⋯F (10.80%). This work is the second report in the literature of a crystal structure of a coordination compound with isatin 3-oxime ligands (coordination chemistry).