3-Methyl-1,5-diphenyl-4,5-dihydro-1H-pyrazole

In the title compound, C16H16N2, the dihydropyrazole ring adopts a shallow envelope conformation, with the C atom bearing the phenyl group displaced by 0.298 (2) Å from the other atoms (r.m.s. deviation = 0.015 Å). The dihedral angles between the four near coplanar atoms of the central ring and the N- and C-bonded phenyl groups are 13.49 (13) and 82.22 (16)°, respectively.

In the title compound, C 16 H 16 N 2 , the dihydropyrazole ring adopts a shallow envelope conformation, with the C atom bearing the phenyl group displaced by 0.298 (2) Å from the other atoms (r.m.s. deviation = 0.015 Å ). The dihedral angles between the four near coplanar atoms of the central ring and the N-and C-bonded phenyl groups are 13.49 (13) and 82.22 (16) , respectively.  MM thanks the IOE, University of Mysore, for the award of a fellowship. We thank the Solid Sate and Structural Chemistry Unit, IISc, Bangalore, for the data collection.

Related literature
supplementary materials Acta Cryst. (2013). E69, o602 [doi:10.1107/S1600536813007575] we have synthesized the title compound to study its crystal structure in order to understand the structure-activity relationship for its biological activity.

3-
The title compound C 16 H 16 N 2 , contains two benzene rings (C1-C6 and C8-C13), these two rings are attached to the central pyrazole ring and the molecules are connected by non classical hydrogen bonds. The dihydropyrazole ring is a shallow envelope, with atom C7 displaced from the other four atoms by 0.298 (2)Å. The dihedral angles between the four near coplanar atoms of the central ring and the N-and C-bonded phenyl groups are 13.49 (13) and 82.22 (16)°, respectively. Bond lengths and bond angles are within normal ranges and are comparable to related structures (Baktır et al., 2011& Fun et al., 2011.

Experimental
A mixture of 4-phenylbut-3-en-2-one (0.05 mmol), phenyl hydrazine hydrochloride (0.05 mmol) and sodium acetate (0.05 mmol) in ethyl alcohol (25 ml) was stirred at room temperature for 1 h. The progress of the reaction was monitored by TLC. After the completion of the reaction, the mixture was poured into ice cold water. The solid formed was separated and crystallized with acetonitrile to get the title compound as yellow blocks.

Refinement
All hydrogen atoms were located geometrically with C-H = 0.93-0.97) Å and allowed to ride on their parent atoms with U iso (H) = 1.2U eq (aromatic C).   Packing diagram of molecule, viewed along the crystallographic b axis. where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.001 Δρ max = 0.14 e Å −3 Δρ min = −0.10 e Å −3 Special details Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles Refinement. Refinement on F 2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses 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 observed criterion of F 2 > σ(F 2 ) is used only for calculating -R-factor-obs 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.