Crystal structures of salen-type ligands 2-[(1E)-({1-(3-chloro-phen-yl)-2-[(E)-(2-hy-droxy-benzyl-idene)amino]-prop-yl}imino)-meth-yl]phenol and 2-[(1E)-({1-(4-chloro-phen-yl)-2-[(E)-(2-hy-droxy-benzyl-idene)amino]-prop-yl}imino)-meth-yl]phenol.

Abstract

The title compounds, C23H21ClN2O2, differ from each other only by the position of the Cl atom on the corresponding benzene ring: meta relative to the central sp3 C atom for (I) and para for (II). In (I), the hy-droxy-phenyl rings are almost parallel, the dihedral angle between the mean planes being 9.2 (2)°, but in (II), the relative position of the ring is different, characterized by a dihedral angle of 48.5 (1)°. Compound (I) features intra-molecular O-H⋯N and inter-molecular C-H⋯O hydrogen bonds, while in (II), intra-molecular O-H⋯N, C-H⋯N hydrogen bonds and weak inter-molecular C-H⋯π inter-actions are observed. Compound (I) was refined as an inversion twin.