(E)-4-(2-Chlorobenzylideneamino)-3-(2-chlorophenyl)-1H-1,2,4-triazole-5(4H)-thione–(E)-1,5-bis(2-chlorobenzylidene)thiocarbonohydrazide–methanol (1/1/1)

In the title compound, C15H12Cl2N4S·C15H10Cl2N4S·C2H6O, the two chlorophenyl rings of the triazole derivative form dihedral angles of 65.7 (2) and 44.2 (2)° with the triazole ring. In the thiocarbonohydrazide derivative, the dihedral angle between the two chlorophenyl rings is 5.4 (2)°. In the crystal, the triazole, thiocarbonohydrazide and methanol molecules are linked by N—H⋯O, N—H⋯S and O—H⋯S hydrogen bonds, forming a hexameric unit.


S1. Comment
The synthesis and structural investigation of Schiff base compounds have attracted much attention due to their interesting structures and potential applications. Some of them have biological activities (Liang, 2003;Bacci et al., 2005). They also play an important role in the development of coordination chemistry as well as inorganic biochemistry, catalysis and optical materials (Ren et al., 1999;Yang et al. 2005;Sen et al. 1998).
The dihedral angle between the C1-C6 and C10-C15 rings is 5.4 (2)°. Two triazole, two thiocarbonohydrazide and two methanol molecules are linked by N-H···O, N-H···S and O-H···S hydrogen bonds to form a hexamer.

S2. Experimental
The Schiff base compound was synthesized according to the modified method of Xia et al. (2007). A mixture of (2chlorophenyl)methanamine and thiourea in methanol (30 ml) was refluxed for 3 h and filtered. The filtrate was placed for sevaral days yielding colourless block-shaped crystals. (yield 79%). Elemental analysis: Calculated for C 32 H 28 Cl 4 N 8 OS 2 : C 51.48, H 3.78, N 15.01; found: C 51.51, H 3.49, N 15.13.

S3. Refinement
The H atoms were found in a difference map, then placed in idealized positions (C-H = 0.93-0.97 Å, N-H = 0.86 Å and O-H = 0.82 Å), and refined using a riding model, with U iso (H) = 1.2U eq (C,N) and 1.5U eq (O,C methyl ).

Figure 1
The asymmetric unit of the title compound, with atom labels and 30% probability displacement ellipsoids for non-H atoms. H atoms have been omitted for clarity.

(E)-4-(2-Chlorobenzylideneamino)-3-(2-chlorophenyl)-1H-1,2,4-triazole-5(4H)-thione-(E)-1,5-bis(2chlorobenzylidene)thiocarbonohydrazide-methanol (1/1/1)
where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.001 Δρ max = 0.28 e Å −3 Δρ min = −0.25 e Å −3 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.