5-((Methoxyimino){2-[(2-methylphenoxy)methyl]phenyl}methyl)-N-phenyl-1,3,4-oxadiazol-2-amine

In the title molecule, C24H22N4O3, the plane of the oxadiazole ring forms a dihedral angle of 32.41 (12)° with that of the phenyl ring and dihedral angles of 74.51 (10) and 56.38 (10)° with the planes of the benzene rings. In the crystal, pairs of N—H⋯N hydrogen bonds link molecules into inversion dimers featuring R 2 2(8) graph-set motifs.

In the title molecule, C 24 H 22 N 4 O 3 , the plane of the oxadiazole ring forms a dihedral angle of 32.41 (12) with that of the phenyl ring and dihedral angles of 74.51 (10) and 56.38 (10) with the planes of the benzene rings. In the crystal, pairs of N-HÁ Á ÁN hydrogen bonds link molecules into inversion dimers featuring R 2 2 (8) graph-set motifs.
RK acknowledges the Department of Science & Technology for the purchase of a single-crystal X-ray diffractometer sanctioned as a National Facility under Project No. SR/ S2/CMP-47/2003. Supporting information for this paper is available from the IUCr electronic archives (Reference: LH5692).

Comment
Derivatives of oxadiazole systems are a growing research interest, as they are precursors to functional N-heterocyclic compounds, as well as being used in pharmaceuticals as metabolically stable surrogates and photographically active systems (Schnurch et al., 2006;Crabtree, 2005;Venkatakrishnan, et al., 2000). Symmetrical and unsymmetrical 1,3,4oxadiazoles have been reported to be versatile compounds displaying a variety of biological effects, which include antiinflammatory (Omar et al., 1996), antifungal (Talawar et al., 1996 and antimicrobial (Hamad et al., 1996) activities.
They have been utilized as bioisosteres of the carboxamide moiety in benzodiazepine receptor agonists, muscarinic receptor agonists, NK1 receptor antagonists, and Phe-Gly peptidomimetics (Tully et al., 1991;Barry et al., 1991;Ladduwahetty et al., 1996;Borg et al., 1999). Moreover, oxadiazole derivatives have been widely used as electronconducting and hole-blocking materials in moleculebased as well as polymeric light-emitting devices (LEDs) due to the electron-deficient and favourable electron-transport properties of the oxadiazole rings (Brown et al., 1992).
A solution of 10% iodine in potassium iodide was added drop wise with stirring till the color of iodine persisted. The mixture was refluxed on a water bath for 4 h, and then left to cool. The separated solid was filtered off washed with water, by the process of slow evaporation recrystallized it from methanol.

Refinement
H6′ attached to N6 was located in a difference Fourier map and refined isotropically. The remaining H atoms were positioned geometrically and were treated as riding on their parent C atoms, with C-H distances of 0.93-0.97 Å; and with U iso (H) = 1.2U eq (C), except for the methyl groups where U iso (H) = 1.5U eq (C),.

Figure 1
The molecular structure of the title compound with ellipsoids drawn at the 40% probability level. H atoms are shown as small spheres of arbitrary radii.  Part of the crystal structure with hydrogen bonds shown as dashed lines showing and inversion dimer.

5-((Methoxyimino){2-[(2-methylphenoxy)methyl]phenyl}methyl)-N-phenyl-1,3,4-oxadiazol-2-amine
Crystal data Hall symbol: -P 1 a = 7.0629 (4) Å b = 12.5553 (9) Å c = 13.3705 (11) Å α = 68.321 (7) Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.