2-[3-(4-Chlorophenyl)-5-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]-4-phenyl-1,3-thiazole

In the title compound, C24H17ClFN3S, the pyrazole ring is almost planar (r.m.s. deviation = 0.030 Å). With the exception of the methine-bound benzene ring, which forms a dihedral angle of 85.77 (13)° with the pyrazole ring, the remaining non-C atoms lie in an approximate plane (r.m.s. deviation = 0.084 Å) so that overall the molecule has a T-shape. In the crystal, centrosymmetrically related molecules are connected via π–π interactions between pyrazole rings [centroid–centroid distance = 3.5370 (15) Å] and these stack along the a axis with no specific interactions between them.

In the title compound, C 24 H 17 ClFN 3 S, the pyrazole ring is almost planar (r.m.s. deviation = 0.030 Å ). With the exception of the methine-bound benzene ring, which forms a dihedral angle of 85.77 (13) with the pyrazole ring, the remaining non-C atoms lie in an approximate plane (r.m.s. deviation = 0.084 Å ) so that overall the molecule has a T-shape. In the crystal, centrosymmetrically related molecules are connected viainteractions between pyrazole rings [centroidcentroid distance = 3.5370 (15) Å ] and these stack along the a axis with no specific interactions between them.

Comment
The title compound (I) was investigated owing to the established biological activities exhibited by related pyrazolin-1carbothioamides (Abdel-Wahab et al. 2012;Lv et al., 2011;Chimenti et al., 2010;Abdel-Wahab et al. 2009). Herein, the crystal and molecular structure of (I) is described.
In (I), Fig. 1, the pyrazolyl ring is quite planar with a r.m.s. deviation of the five atoms being 0.030 Å. This is in contrast to the situation observed in the recently described derivative with a methyl rather than a chloride (Abdel-Wahab et al. 2013) whereby an envelope conformation was found for each of the two independent molecules; the methine-C atom was the flap atom in each case. In (I), the dihedral angle between the pyrazolyl and thiazole (r.m.s. deviation = 0.002 Å) rings is 2.83 (13)°. The thiazole-bound benzene ring is co-planar; dihedral angle = 4.34 (13)° with the thiazole. About the pyrazolyl ring, the chlorobenzene ring is co-planar, dihedral angle = 6.92 (14)°, but the benzene ring bound at C11 is perpendicular, dihedral angle = 85.77 (13)°. Thus, there are two planar, mutually perpendicular domains in the molecule which adopts a T-shape, as was the case for the aforementioned literature structure but which exhibited some twists, e.g.
The most prominent feature of the crystal packing is the formation of dimeric aggregates between centrosymmetrically related molecules via π-π interactions between pyrazolyl rings [inter-centroid distance = 3.5370 (15) Å for symmetry   Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figure 1
The molecular structure of (I) showing displacement ellipsoids at the 35% probability level.

Figure 2
A view of the dimeric aggregate in (I) sustained by π-π interactions, shown as purple dashed lines.  A view of the crystal packing in projection down the a axis. The π-π interactions are shown as purple dashed lines. are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.