Crystal structure of bis{3-(3,5-dichlorophenyl)-5-[6-(1H-pyrazol-1-yl)pyridin-2-yl]-4H-1,2,4-triazol-4-ido}iron(II) methanol disolvate

Abstract

The asymmetric unit of the title compound, [FeII(C16H9Cl2N6)2]·2CH3OH, consists of half of a charge-neutral complex molecule and a discrete methanol molecule. The planar anionic tridentate ligand 2-[5-(3,5-dichlorophenyl)-4H-1,2,4-triazol-3-ato]-6-(1H-pyrazol-1-yl)pyridine coordinates to the FeII ion through the N atoms of the pyrazole, pyridine and triazole groups, forming a coordination sphere of the central ion that deviates moderately from an octahedral geometry. The average Fe—N bond distance is 1.953 Å, indicating the low-spin state of the FeII ion. The cone-like-shaped molecules, nested into each other, are linked through double weak C—H(pz)...π(ph) interactions into mono-periodic columns, which are further linked through weak C—H...N′/C′ interactions into di-periodic layers. The layers interact through double weak C–H(ph)...Cl bonds with neighbouring molecules. Energy framework analysis at the B3LYP/6–31 G(d,p) theory level reproduces the strong interaction within the layers and the weaker interlayer interactions. Intermolecular contacts were quantified using Hirshfeld surface analysis and two-dimensional fingerprint plots, the relative contributions of the contacts to the crystal packing being H...H 26.1%, H...C/C...H 24.4%, H...Cl/Cl...H 18.9% and H...N/N...H 12.1%.