(2E)-1-[5-Methyl-1-(4-methylphenyl)-1H-1,2,3-triazol-4-yl]-3-[4-(piperidin-1-yl)phenyl]prop-2-en-1-one1

Two independent molecules comprise the asymmetric unit of the title compound, C24H26N4O. The major difference between them is found in the relative orientation of the triazole-bound p-tolyl group which have the opposite sense of twist [N—N—C—C torsion angles = 55.8 (3) and −49.8 (3)°]. The chalcone residue is almost coplanar with the triazole ring [N—C—C—O and C—C—C—C torsion angles = −178.9 (2) and −178.5 (2)°, respectively; cf. 177.9 (3) and 168.5 (3)°, respectively, in the second molecule]. The conformation about each C=C double bond is E and in each case the triazole methyl group is syn to the carbonyl O atom. In the crystal, molecules aggregate into layers parallel to (-113). The first independent molecule self-associates into a layer via C—H⋯O and C—H⋯π interactions. By contrast, layers comprising the second independent molecule do not feature specific interactions between molecules. The global crystal packing comprises alternating layers.

Two independent molecules comprise the asymmetric unit of the title compound, C 24 H 26 N 4 O. The major difference between them is found in the relative orientation of the triazole-bound p-tolyl group which have the opposite sense of twist [N-N-C-C torsion angles = 55.8 (3) and À49.8 (3) ]. The chalcone residue is almost coplanar with the triazole ring [N-C-C-O and C-C-C-C torsion angles = À178.9 (2) and À178.5 (2) , respectively; cf. 177.9 (3) and 168.5 (3) , respectively, in the second molecule]. The conformation about each C C double bond is E and in each case the triazole methyl group is syn to the carbonyl O atom. In the crystal, molecules aggregate into layers parallel to (113). The first independent molecule selfassociates into a layer via C-HÁ Á ÁO and C-HÁ Á Á interactions. By contrast, layers comprising the second independent molecule do not feature specific interactions between molecules. The global crystal packing comprises alternating layers. 528 parameters H-atom parameters constrained Á max = 0.19 e Å À3 Á min = À0.19 e Å À3 Table 1 Hydrogen-bond geometry (Å , ).

Comment
Triazole-based chalcone derivatives exhibit a range of biological activities (Abdel-Wahab et al., 2012;Guantai et al., 2010) and in this connection, the title compound was synthesized and characterized crystallographically.
In (I), Fig. 1, two independent molecules comprise the asymmetric unit. As illustrated in the overlay diagram, Fig (4) and 1.330 (4) Å] is E, and in each case the triazole-methyl is syn to the carbonyl-O atom. In these respects, the structure of (I) resembles closely that of a recently described derivative (Abdel-Wahab et al., 2013). The major difference between the two molecules in (I) is found in the relative orientation of the triazole-bound p-tolyl groups. Although having similar dihedral angles, see above, the orientations of the rings have the opposite sense as seen in the value of the N2- In the crystal structure, centrosymmetrically related O1-containing molecules associate into dimers via C-H···O interactions and these are connected into a supramolecular layer, parallel to (-1 1 3), via C-H···π interactions, Fig. 3 and Table 1. The O2-containing molecules also assemble into a layer but without specific interactions between them. The global crystal packing comprises alternating layers of O1-and O2-containing layers with no specific interactions between them, Fig. 4.

Experimental
The title compound was prepared following a reported method (Abdel-Wahab et al., 2012). Yellow prisms were obtained from its DMF solution by slow evaporation at room temperature.

Refinement
Carbon-bound H-atoms were placed in calculated positions (C-H = 0.93 to 0.97 Å) and were included in the refinement in the riding model approximation, with U iso (H) = 1.2-1.5U equiv (C).

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

Figure 2
Overlay diagram of the two independent molecules comprising the asymmetric unit of (I). The O1-(red image) and O2containing (blue) molecules have been superimposed so that the five-membered rings are coincident.   A view of the crystal packing in projection down the a axis, highlighting the alternating layers of O1-and O2-containing molecules. The C-H···O and C-H···π interactions are shown as orange and purple dashed lines, respectively.

Special details
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness 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 threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) 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.