4-Chloro-N-methylbenzamide

There are two molecules in the asymmetric unit of the title compound, C8H8ClNO, which are linked in the crystal structure via N—H⋯O hydrogen bonds into chains along the b axis. C—H⋯O contacts also occur. The benzene ring makes dihedral angles of 5.9 (1) and 16.7 (1)°with the attached amide group in the two independent molecules.


4-Chloro-N-methylbenzamide Juan Yuan and Yan-Ju Liu Comment
Benzamide derivatives exhibit interesting biological activities such as antibacterial and antifungal effects (Lee et al., 2009). We report here the crystal structure of the title compound 4-chloro-N-methylbenzamide, (I).
The molecular structure of (I) is shown in Fig. 1. The title compound was connected together via N-H···O intermolecular hydrogen bonds (Table 1)

Experimental
The title compound, (I) was prepared by a method reported in literature (Lee et al., 2009). 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, 0.96 Å for methyl H and 0.86 Å for N-H, respectively. The U iso (H) = xU eq (C), where x = 1.2 for aromatic H and N-H, and x = 1.5 for methyl H.

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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq Cl1