A monoclinic polymorph of N-(3-chloro-phen-yl)benzamide

Abstract

The title compound, C13H10ClNO, (I), is a polymorph of the structure, (II), first reported by Gowda et al. [Acta Cryst. (2008), E64, o462]. In the original report, the compound crystallized in the ortho-rhom-bic space group Pbca (Z = 8), whereas the structure reported here is monoclinic P21/c (Z = 4). The principal difference between the two forms lies in the relative orientations of the phenyl and benzene rings [dihedral angle = 8.90 (13)° for (I) and 61.0 (1)° for (II)]. The inclination of the amide -CONH- units to the benzoyl ring is more similar [15.8 (7)° for (I) and 18.2 (2)° for (II)]. In both forms, the N - H bonds are anti to the 3-chloro substituents of the aniline rings. In the crystal, inter-molecular N - H⋯O hydrogen bonds form C(4) chains along c. These chains are bolstered by weak C - H⋯O inter-actions that generate R 2 1(6) and R 2 1(7) ring motifs.