2-(4-Chlorophenyl)-N-(1,3-thiazol-2-yl)acetamide

In the title compound, C11H9ClN2OS, the thiazole ring is nearly planar (r.m.s. deviation = 0.003 Å) and forms a dihedral angle of 64.18 (7)° with the bezene ring. In the crystal, inversion dimers linked by pairs of N—H⋯Nt (t = thiazole) hydrogen bonds generate R 2 2(8) loops.


Comment
In continuation of our work on synthesis of amides (Fun et al., 2011a(Fun et al., , 2011b(Fun et al., , 2012a(Fun et al., , 2012b, we report herein the crystal structure of the title compound.
Experimental 4-Chlorophenylacetic acid (0.170 g, 1 mmol), 2-aminothiazole (0.1 g, 1 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (1.0 g, 0.01 mol) were dissolved in dichloromethane (20 ml). The mixture was stirred in presence of triethylamine at 273 K for about 3 h. The contents were poured into 100 ml of ice-cold aqueous hydrochloric acid with stirring. The resulting solution was extracted thrice with dichloromethane. The organic layer was washed with saturated NaHCO 3 solution and brine solution, dried and concentrated under reduced pressure to give the title compound (I). Orange blocks were grown from an acetone and toluene (1:1) solvent mixture by the slow evaporation method (m.p.: 441K).

Refinement
Atom H1N2 was located in a difference Fourier map and refined freely [N-H = 0.868 (19) Å]. The remaining H atoms were positioned geometrically and refined using a riding model with C-H = 0.93 or 0.97 Å and U iso (H) = 1.2 U eq (C).

Figure 2
The crystal structure of the title compound, viewed along the b axis. H atoms not involved in hydrogen bonds (dashed lines) have been omitted for clarity.

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 > 2sigma(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.