1-[4-(Difluoromethoxy)phenyl]-N-(3,4-dimethoxyphenyl)-1H-1,2,4-triazole-3-carboxamide

Two crystallographically independent molecules, A and B, with similar conformations are present in the asymmetric unit of the title compound, C18H16F2N4O4. In molecule A, the plane of the 1,2,4-triazole ring is tilted relative of the 4-difluoromethoxy-substituted and the 3,4-dimethoxy-substituted benzene rings by 6.5 (2) and 16.4 (1)°, respectively. The –CHF2 group is twisted away from the plane of the benzene ring, with a dihedral angle between the O—C bond of the OCHF2 group and the plane of the adjacent phenyl ring of 38.6 (3)°. The corresponding parameters for molecule B are 7.7 (1), 9.5 (2) and 25.2 (2)°. In both molecules, the conformations are stabilized by intramolecular N—H⋯N and C—H⋯O hydrogen bonds. There are also C—H⋯π contacts between the methyl groups and the benzene rings, and π–π stacking interactions between the benzene rings of adjacent parallel A molecules [centroid–centroid distance = 3.8942 (17) Å]. π–π interactions are also observed between the triazole ring and one of the benzene rings of parallel B molecules [centroid–centroid distance = 3.7055 (16) Å].

The conformations of the two molecules are stabilized by intramolecular N-H···N hydrogen bonds and intra and intermolecular C-H···O hydrogen bonds (Table 1). There are also C-H···π contacts between the methyl groups and the benzene rings. The closest distance between the benzene rings of adjacent parallel A molecules is 3.33 Å indicating π-π stacking.
Between parallel B molecules π-π interactions are observed between the triazole ring and one of the benzene rings (the closest distance is 3.32 Å). These weak interactions lead to the formation of a three-dimensional network as shown in Fig. 2.
supplementary materials sup-2 The reaction was complete after 10 h (the reaction progress was controlled by TLC). The mixture was cooled to room temperature and the solvent was evaporated. The solid product was collected and recrystallized from 2-propanol.

Refinement
H atoms were placed in calculated positions with C-H = 0.93-0.98 Å, N-H = 0.86 Å, and refined in riding mode with U iso (H) = 1.5U eq (C) for methyl C, and U iso (H) = 1.2U eq (C, N) for all other H atoms.

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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.
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )