C25H19N5O3S, monoclinic, P21/c (no. 14), a = 16.715(2) Å, b = 11.2677(15) Å, c = 12.6490(17) Å, β = 110.818(2)°, V = 2226.7(5) Å3, Z = 4, Rgt(F) = 0.0424, wRref(F2) = 0.1037, T = 296 K.

CCDC no.: 1499592One of the two independent molecules is shown in the figure. Tables 1 and 2 contain details on crystal structure and measurement conditions and a list of the atoms including atomic coordinates and displacement parameters. Source of materialTo a solution of ethyl 3-phenyl-1H-pyrazole-5-carboxylate (1.08 g, 5.24 mmol) and benzyl chloride (0.66 g, 5.24 mmol) in acetonitrile (25 mL) was added K 2 CO 3 (0.72 g, 5.24 mmol). The mixture was refluxed for 5 h and the precipitate was evaporated to dryness under reduced pressure. The residue was purified by column chromatography on silica gel using ethyl acetate and petroleum ether (1:5, v/v), to obtain the target compound in 5.9% yield. Crystals were obtained by slow evaporation of methanol solution at room temperature. Experimental detailsAll H atoms were placed in idealized positions and treated as riding on their parent atoms, with d(C-H) = 0.96 (methyl) and 0.97 Å (methylene), U iso (H) = 1.5Ueq(C) and DiscussionSome pyrazoles are attractive five-membered nitrogencontaining compounds due to their fluorescence properties