2-Chloro-4-(3,3-dichloroallyloxy)-1-nitrobenzene

In the crystal structure of the title compound, C9H6Cl3NO3, molecules are connected by C—H⋯O hydrogen bonds, forming chains along the b axis. The dihedral angle between the benzene ring and the plane of the nitro group is 16.2 (1)° and that between the benzene ring and the plane of the dichloroallyl group is 10.2 (1)°.

In the crystal structure of the title compound, C 9 H 6 Cl 3 NO 3 , molecules are connected by C-HÁ Á ÁO hydrogen bonds, forming chains along the b axis. The dihedral angle between the benzene ring and the plane of the nitro group is 16.2 (1) and that between the benzene ring and the plane of the dichloroallyl group is 10.2 (1) .

Related literature
For background to the applications of the title compound, see: Kolosov et al. (2002). For the synthesis, see: Walker et al. (2005).
Experimental Crystal data
Data collection: CAD-4 Software (Enraf-Nonius, 1985); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXS97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL. The title compound is an important intermediate in the synthesis of phenanthrenes, which can be utilized to synthesize organic semiconductors and conjugated polymers (Walker et al., 2005). These materials are of wide current interest for applications in electronic and optoelectronic devices including light-emitting diodes (Kolosov et al., 2002). We report here the crystal structure of the title compound, (I), which is of interest to us in this field.
The molecular structure of (I) is shown in Fig. 1. There is an intermolecular contact C-H···O in the title compound, forming molecular chains along the b axis direction (Table 1, Fig. 2). These molecular chains are linked by weak π-π interactions (Cg1···Cg1 i distance = 3.724 (3) Å, Cg1 is the centroid of ring C1-C6, symmetry code: (i) x, 5/2 -y, -1/2 + z) to give a three-dimensional network, which seems to be very effective in the stabilization of the crystal structure.

Experimental
The title compound, (I) was prepared by a method reported in literature (Walker et al., 2005). The crystals were obtained by dissolving (I) (0.1 g) in methanol (30 ml) and evaporating the solvent slowly at room temperature for about 8 d.

Refinement
All H atoms were positioned geometrically and constrained to ride on their parent atoms, with C-H = 0.93 Å for aromatic H and 0.96 Å for alkyl H, respectively. The U iso (H) = xU eq (C), where x = 1.2 for aromatic H and x = 1.5 for other H.

Figure 2
A packing diagram of (I) viewed along the a axis (C-H···O hydrogen bonds are shown as broken lines). 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.