A second monoclinic polymorph of 1-benzyl-N-methyl-1H-pyrrole-2-carboxamide

In the title compound, C13H14N2O, the Npyrrole—C(H2)—C—C torsion angle is −7.7 (3)° and the dihedral angle between the pyrrole and benzene rings is 83.6 (2)°. In the crystal, intermolecular N—H⋯O hydrogen bonds link the molecules into chains extending along the c axis. We have previously reported another polymorphic form of this title compound, which has the same space group with different cell parameters: a = 9.8285 (18) Å, b = 23.588 (4) Å, c = 9.9230 (17) Å, β = 90.107 (3)°, Z = 8 and V = 2300.5 (7) Å3 [Zeng et al. (2010 ▶). Acta Cryst. E66, o2051].


Related literature
For details of the synthesis, see: Zeng et al. (2010); For the previously reported polymorph, see: Zeng et al. (2010) and for a related structure, see: Zeng et al. (2007).
As reported, the previous polymorph structure show that the asymmetric unit of the compound contains two independent molecules, which differ in the twist of the phenyl ring: the N pyrrole -C(H 2 )-C-C torsion angles are -73.0 (3)° and 17.1 (3)°, respectively. And for the present one, the asymmetric unit contains just one molecule, in this molecule, the N pyrrole -C(H 2 )-C-C torsion angle is -7.7 (3)°, the dihedral angle between the pyrrole plane and the benzene plane is 83.60 (2)°.
The crystal packings of these two structures are differences also. In the previous polymorph structure, molecules are linked through N-H···O hydrogen bonds, generating chains extending to the a axis (shown in Fig. 3). And for the present one, N-H···O hydrogen bonds link molecules together to forming chains extending to the c axis (shown in Fig. 2).

Experimental
The title compound was synthesized according to the literature procedure (Zeng et al., 2010). The product was dissolved in the mixture of ethanol / water (2:1 v/v), colorless crystals suitable for X-ray analysis were obtained over a period of five days by slow evaporation at room temperature of the solution.

Refinement
All non-H atoms were refined with anisotropic displacement parameters. The H atoms were positioned geometrically [C-H = 0.97Å for CH 2 , 0.96Å for CH 3 , 0.93Å for CH(aromatic) and N-H = 0.86 Å] and refined using a riding model, with U iso = 1.2U eq (1.5U eq for the methyl group) of the parent atom.  Fig. 1. The molecular structure of the title compound, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.