4-Amino-3-(1-naphthyloxymethyl)-1H-1,2,4-triazole-5(4H)-thione

In the title compound, C13H12N4OS, the dihedral angle between the triazole and naphthalene ring systems is 67.42 (5)°. In the crystal, adjacent molecules are linked via two pairs of intermolecular N—H⋯S interactions, forming R 2 2(8) and R 2 2(10) ring motifs. Weak C—H⋯S interactions generate infinite chains along [001] and the structure is further consolidated by C–H⋯π bonds and aromatic π⋯π stacking interactions [distance between the centroids of the triazole rings = 3.2479 (7) Å].

In the title compound, C 13 H 12 N 4 OS, the dihedral angle between the triazole and naphthalene ring systems is 67.42 (5) . In the crystal, adjacent molecules are linked via two pairs of intermolecular N-HÁ Á ÁS interactions, forming R 2 2 (8) and R 2 2 (10) ring motifs. Weak C-HÁ Á ÁS interactions generate infinite chains along [001] and the structure is further consolidated by C-HÁ Á Á bonds and aromatic Á Á Á stacking interactions [distance between the centroids of the triazole rings = 3.2479 (7) Å ].
The amino and mercapto groups of 1,2,4-triazoles serve as readily accessible nucleophilic centers of the preparation of N-bridged heterocycles. Keeping in view of the biological importance, we have synthesized the title compound to study its crystal structure.
Experimental 2-(1-Naphthyloxy)acetohydrazide (21.6 g, 1.00 mmol) was added slowly to a solution of potassium hydroxide (8.4 g, 1.50 mmol) in ethanol (150 ml). The resulting mixture was stirred well until a clear solution was obtained. Carbon disulphide (11.4 g, 1.50 mmol) was added drop-wise and the contents were stirred vigorously. Further stirring was continued for 24 h.
The resulting mixture was diluted with ether (100 ml) and the precipitate formed was collected by filtration, washed with dry ether and dried at 65 /%c under vacuum. It was used for the next step without any purification.
A mixture of the above synthesized potassium dithiocarbazinate (16.5 g, 0.50 mmol), hydrazine hydrate (99 %, 1.00 mmol) and water (2 ml) was heated gently to boil for 30 minutes. Heating was continued until the evacuation of hydrogen sulphide ceased. The reaction mixture was cooled to room temperature, diluted with water (100 ml) and acidified with HCl.
The solid mass that separated was collected by filtration, washed with water and dried. Recrystallization was achieved from ethanol. The yield was 9.25 g (68 %), m. p. 470-471 K (Suresh, 1992).

Refinement
All H atoms were located in a difference Fourier map and refined freely.  Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsoids for non-H atoms.

Special details
Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.
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.