1. 2-(3,4-Dichloro-phen-yl)-N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)acetamide
Aneeka Mahan, Ray J Butcher, Prakash S Nayak, B Narayana, H S Yathirajan Acta Crystallogr Sect E Struct Rep Online. 2013 Mar 1;69(Pt 3):o402-3. doi: 10.1107/S1600536813002341. Epub 2013 Feb 20.
In the title compound, C19H17Cl2N3O2, there are three mol-ecules (A, B and C) in the asymmetric unit and each differs in the conformation adopted. As a result of steric repulsion, the amide group is rotated with respect to both the dichloro-phenyl and 2,3-dihydro-1H-pyrazol-4-yl rings, making dihedral angles of 44.5 (2) and 56.2 (2)°, respectively in A, 51.1 (2) and 54.1 (2)° in B, and 53.8 (2) and 54.6 (2)° in C. The dihedral angles between the dichloro-phenyl and 2,3-dihydro-1H-pyrazol-4-yl rings are 54.8 (2), 76.2 (2) and 77.5 (2)° in mol-ecules A, B and C, respectively, while the 2,3-dihydro-1H-pyrazol-4-yl and phenyl rings make dihedral angles of 45.3 (2), 51.2 (2) and 42.8 (2)°, respectively. In the crystal, two of the mol-ecules are linked through N-H⋯O hydrogen bonding to an adjoining mol-ecule, forming dimers of the R2(2)(10) type, while the third mol-ecule forms such dimers with itself. C-H⋯O inter-actions link the dimers.