Acta Crystallographica Section E (Jan 2009)
2,2′-Dihydroxy-3,3′-[(1E,1′E)-hydrazine-1,2-diylidenedimethylidyne]dibenzoic acid N,N-dimethylformamide disolvate
Abstract
The title compound, C16H12N2O6·2C3H7NO, lies across a crystallographic inversion centre which is situated at the midpoint of the central N—N bond. The substitution at the C=N bond adopts a trans configuration and it is essentially coplanar with the benzene ring [N—C—C—C torsion angles = −173.9 (4) and 6.4 (6)°]. All torsion angles involving non-H atoms are close to 180°. Intramolecular O—H...O and weak C—H...O hydrogen bonds form S(6) and S(5) ring motifs, respectively, while intermolecular O—H...O and weak C—H...O hydrogen bonds connect the Schiff base molecule to solvent dimethylformamide molecules.