3,3'-(m-Phenyl-enedi-oxy)diphthalonitrile.

In the title compound, C(22)H(10)N(4)O(2), the dihedral angles between the mean planes of the central benzene ring and the pendant rings are 79.20 (6) and 80.29 (6)°. The dihedral angle between the pendant rings is 10.27 (7)°.

In the title compound, C 22 H 10 N 4 O 2 , the dihedral angles between the mean planes of the central benzene ring and the pendant rings are 79.20 (6) and 80.29 (6) . The dihedral angle between the pendant rings is 10.27 (7) .

Comment
In the past few years, the semirigidity of molecules have been extensively employed for search of novel functional compounds. For example,a new family of multidentate O-donor ligands with a semirigid V-shaped molecular framework have been used to construct metal-organic coordination frameworks (Wang et al., 2009;Wang et al., 2005), in which some showed interesting properties. Here, we present the structure of a new semirigid organic ligand.
The crystal structure of the title compound is given in Fig. 1. As can be found, all the bond lengths and angles are normal and correspond to those observed in related compound (Huang et al., 2005;Zhang et al., 2007). The aromatic rings (C3-C8 and C15-C20) in sides of the molecule are in the same direction of the aromatic rings(C9-C14) with a cis configuration. The three dihedral angles in the title compound are 79.81Å for C3-C8 and C9-C14, 80.83Å for C15-C20 and C9-C14,and 10.54 Å for C3-C8 and C15-C20, respectively.

Experimental
Resorcinol (0.53 g, 5 mmol) and anhydrous K 2 CO 3 was added to the solution of 2,3-dicyanophenyl nitrate (1.73 g, 10 mmol) in DMSO (25 ml). A kind of brown solution was generated after the solution was stirred for 48 hours at room temperature.
The brown solution was added to 200 ml water, and was stirred for 30 min at room temperature. The precipitate formed was

Refinement
All H atoms were placed in geometrically idealized positions and treated as riding on their parent atoms with C(sp 2 hybrid)-H distances of 0.93Å (U iso (H)=1.2U eq (C)). Fig. 1. The molecular structure of (I). Displacement ellipsoids are drawn at 30% probability level.

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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-supplementary materials sup-3 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.