{2-[(1,3-Benzothiazol-2-yl)methoxy]-5-chlorophenyl}(4-chlorophenyl)methanone

In the title compound, C21H13Cl2NO2S, the benzothiazole ring makes dihedral angles of 0.94 (1) and 70.65 (5)° with the 4-chlorophenylmethanone unit and the 5-chlorophenyl ring, respectively. The dihedral angle between the 4-chlorophenylmethanone unit and the 5-chlorophenyl ring is 66.20 (5)°. The crystal structure consists of dimeric units generated by C—H⋯N hydrogen bonds, further linked by C—H⋯O and C—H⋯π interactions, leading to a three-dimensional network.

In the title compound, C 21 H 13 Cl 2 NO 2 S, the benzothiazole ring makes dihedral angles of 0.94 (1) and 70.65 (5) with the 4chlorophenylmethanone unit and the 5-chlorophenyl ring, respectively. The dihedral angle between the 4-chlorophenylmethanone unit and the 5-chlorophenyl ring is 66.20 (5) . The crystal structure consists of dimeric units generated by C-HÁ Á ÁN hydrogen bonds, further linked by C-HÁ Á ÁO and C-HÁ Á Á interactions, leading to a three-dimensional network.   Table 1 Hydrogen-bond geometry (Å , ).

Related literature
Cg is the centroid of the S1/C1/C6/N1/C7 thiazole ring.  In the title molecule ( Fig. 1), the benzothiazole ring makes dihedral angles of 0.94 (1)° and 70.65 (5)° with the 4-chlorophenylmethanone unit and the 5-chlorophenyl ring, respectively. The dihedral angle between the 4-chlorophenylmethanone unit and the 5-chlorophenyl ring is 66.20 (5)°. The crystal structure consists of dimeric units generated by C-H···N hydrogen bonds, further linked by C-H···O and C-H···π interactions, which lead to a three-dimensional network (Table 1 and Fig. 2, Cg is the centroid of the S1/C1/C6/N1/C7 thiazole ring). The crystal structure consists of dimeric units generated by C-H···N hydrogen bonds, further linked by C-H···O and C-H···π interactions, which lead to a threedimensional network (Table 1 and Fig. 2).

Experimental
A mixture of (2-chloromethyl)benzo[d]thiazole (1 mmol) and (5-chloro-2-hydroxyphenyl)(4-chlorophenyl)methanone (1 mmol) and in dry THF, dry potassium carbonate (1 mmol) was added and stirred at room temperature. The reaction mixture was added and the reaction mixture was stirred at room temperature for 14 h. The reaction mixture was concentrated to remove the solvent, diluted with ethyl acetate, washed with water, brine solution and dried over anhydrous sodium sulfate. The organic layer was concentrated to yield a residue which was purified by column chromatography using ethyl acetate and n-hexane as eluent (7:3, Rf = 0.73) to afford the product in 83% as a brown solid (m. p. 448 (2) K). Suitable crystals for single-crystal X-ray study were obtained from dichloromethane solvent using slow evaporation technique at room temperature.

Refinement
All H atoms were positioned geometrically and refined using a riding model, with C-H = 0.95 Å for aryl and 0.99 Å for methylene H atoms. U iso (H) = 1.2U eq (C) for aryl and methylene H atoms.

Figure 1
The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are presented as small spheres of arbitrary radius.  Special details Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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.