2-Amino-N-(2-hydroxy-3-methoxybenzylidene)aniline

In the title compound, C14H14N2O2, the dihedral angle between the two benzene rings is 9.67 (10)°. Two intramolecular O—H⋯N and N—H⋯N hydrogen bonds involving the hydroxy and amino groups generate S(6) and S(5) ring motifs, respectively. In the crystal structure, N—H⋯O hydrogen bonds link neighboring molecules. Molecules are also stacked in a head-to-tail fashion along the c axis through π–π interactions [centroid–centroid separation of 3.7357 (12) Å] and are further linked by weak intermolecular C—H⋯π interactions, giving a zigzag arrangement along the b axis.

In the title compound, C 14 H 14 N 2 O 2 , the dihedral angle between the two benzene rings is 9.67 (10) . Two intramolecular O-HÁ Á ÁN and N-HÁ Á ÁN hydrogen bonds involving the hydroxy and amino groups generate S(6) and S(5) ring motifs, respectively. In the crystal structure, N-HÁ Á ÁO hydrogen bonds link neighboring molecules. Molecules are also stacked in a head-to-tail fashion along the c axis through interactions [centroid-centroid separation of 3.7357 (12) Å ] and are further linked by weak intermolecular C-HÁ Á Á interactions, giving a zigzag arrangement along the b axis.

Comment
Imines are an important class of compounds and rank among the most versatile synthetic organic intermediates, which are important for the synthesis of biologically important compounds (Singh & Dash, 1988;More et al., 2001;Baseer et al., 2000;El-Masry et al., 2000;Kabeer et al., 2001;Kuz'min et al., 2000;Desai et al., 2001). Berger (2001) evaluated some bis-Schiff bases using 1138 and Sc-7 yeast assays, and a A2780 cytotoxicity test. They showed significant activity in a single dose test. The reactions of some phenolic aldehydes with o-phenylenediamine have been examined in some detail including the isolation of the title compound (Latif et al., 1983). Our group has been actively involved in synthesizing bis-Schiff bases and investigating their DNA binding ability using spectroscopic techniques employing calf thymus DNA (Shah et al., 2008).
We have also obtained single crystals of benzimidazole and the bis-Schiff base derived from the title compound (I) and their structures are consistent with those reported earlier (Elerman & Kabak, 1997;Liu et al., 2006). However, the crystal structure of compound (I) was never reported and we present its structure here (Fig. 1).

Experimental
The synthetic method has been described earlier (Al-Douh et al., 2006, 2007. Single crystals suitable for X-ray diffraction were obtained by evaporation of a n-hexane solution at room temperature.

Refinement
The H-atom attached to O1 is located from the difference Fourier map and refined as riding with the parent atom with an isotropic thermal parameter 1.2 times that of the parent atom. The methyl hydrogen atoms were fixed geometrically and refined using a rotating model with isotropic thermal parameters 1.5 that of the parent atom. The remaining hydrogen atoms were located in a difference map and refined freely with their isotropic thermal parameters 1.2 times those of the parent atoms. The highest peak is located 0.96 Å from H2. The deepest hole is located 0.41 Å from H1O1. Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atomic numbering. Intramolecular H bonds are drawn as dashed lines.   0.0165 (9) 0.0211 (9) 0.0161 (9) 0.0027 (7) 0.0049 (7) 0.0019 (7)  C13 0.0178 (10) 0.0188 (9) 0.0130 (9) −0.0004 (7) 0.0003 (7) 0.0006 (7)