2-((E)-{2-[(1E)-(2,4-Dihydroxy-benzyl-idene)amino]phen-yl}iminiometh-yl) -5-hydroxy-phenolate methanol solvate

Abstract

The asymmetric unit of the title compound, C20H16N2O4·CH3OH, contains two Schiff base zwitterions and two methanol solvent mol-ecules. The dihedral angles between the central benzene ring and the two outer benzene rings of the Schiff base are 2.57 (7) and 52.30 (7)° in one mol-ecule and 5.83 (7) and 49.82 (7)° in the other mol-ecule. Intra-molecular O - H⋯N and N - H⋯O hydrogen bonds generate S(6) ring motifs, whereas intra-molecular N - H⋯N hydrogen bonds generate S(5) ring motifs. In the crystal structure, O - H⋯O, hydrogen bonds and weak C - H⋯O inter-actions link the mol-ecules into one-dimensional chains along the b-axis direction and are further connected by O - H⋯O and weak C - H⋯O inter-actions into a three-dimensional network. C - H⋯π and π-π inter-actions [centroid-centroid distances = 3.6228 (9) and 3.6881 (9) Å] are also observed in the crystal structure. © 2008.