Dichlorodiphenoxymethane

The title compound, C13H10Cl2O2, is a mixed derivative of orthocarbonic acid. The non-crystallographic symmetry of the molecule is close to C 2v. The aromatic residues are oriented in a syn conformation with respect to the Cl atoms. The least-squares planes through the phenyl rings enclose an angle of 36.11 (10)°. The C—O bonds at the central carbon are relatively short, and the O—C—O and Cl—C—Cl angles are smaller than the tetrahedral angle. These metrical peculiarities including a molecular symmetry close to C 2v are also observed in density functional theory (DFT) calculations, thus ruling out the decisive influence of intermolecular forces in the crystal structure. Accordingly, only few and weak intermolecular interactions are found. At distances smaller than the sum of the van der Waals radii, only two attractive interactions are detected: a weak C—H⋯O and a weak C—H⋯Cl hydrogen bond to one of the two potential acceptor atoms each.

The title compound, C 13 H 10 Cl 2 O 2 , is a mixed derivative of orthocarbonic acid. The non-crystallographic symmetry of the molecule is close to C 2v . The aromatic residues are oriented in a syn conformation with respect to the Cl atoms. The leastsquares planes through the phenyl rings enclose an angle of 36.11 (10) . The C-O bonds at the central carbon are relatively short, and the O-C-O and Cl-C-Cl angles are smaller than the tetrahedral angle. These metrical peculiarities including a molecular symmetry close to C 2v are also observed in density functional theory (DFT) calculations, thus ruling out the decisive influence of intermolecular forces in the crystal structure. Accordingly, only few and weak intermolecular interactions are found. At distances smaller than the sum of the van der Waals radii, only two attractive interactions are detected: a weak C-HÁ Á ÁO and a weak C-HÁ Á ÁCl hydrogen bond to one of the two potential acceptor atoms each.

Comment
The title compound (I) was prepared as starting material for the synthesis of spirocyclic orthocarbonates.
In the molecule the two aromatic moieties are oriented syn with respect to the Cl atoms (Fig. 1). The bond lengths between the central C atom and the O atoms are slightly shorter than in related tetraaryloxymethanes (Narasimhamurthy et al., 1990).
Unexpectedly, both the O-C-O and the Cl-C-Cl angles are smaller than the tetrahedral angle. The best planes through the phenyl moieties enclose an angle of 36.11 (10)°.
The molecular packing is shown in Figure 2. Below the limit of the sum of the van-der-Waals radii, one weak C-H···O and one weak C-H···Cl hydrogen bond were found in the asymmetric unit as well as an electrostatically repulsive C-H···H-C contact precisely at the vdW radii sum. No π stacking and no C-H···π contacts were observed within this cutoff criterion.
In agreement with the only weak intermolecular forces, the short bonds to the central carbon atom as well as the small bond angles mentioned above are corroborated by a DFT calculation on the B3LYP/6-311+G(2 d,p) level of theory.

Experimental
The title compound was prepared according to a published procedure (Bromley et al., 1996) upon chlorination of diphenylcarbonate with PCl 5 . Crystals suitable for X-ray analysis were obtained directly from the solid reaction product.

Refinement
H atoms were refined as riding on their parent atoms with U iso as the 1.2-fold of the pilot atom's U eq . Fig. 1. The molecular structure of (I), with atom labels and anisotropic displacement ellipsoids (drawn at 50% probability level) for non-H atoms.