1,2-Bis(2,4-dinitrophenyl)disulfane

In the title molecule, C12H6N4O8S2, the dihedral angle between the benzene rings is 77.00 (8)°. The mean planes of the nitro groups are twisted slightly from the benzene rings, forming dihedral angles in the range 2.3 (2)–8.6 (3)°. The S—S bond length is 2.0458 (7) Å. Each S atom is essentially coplanar with the benzene ring to which it is attached, with deviations from the ring planes of 0.0163 (5) and 0.0538 (5) Å. In the crystal, molecules are linked through weak C—H⋯O hydrogen bonds, forming a two-dimensional network parallel to (001).

In the title molecule, C 12 H 6 N 4 O 8 S 2 , the dihedral angle between the benzene rings is 77.00 (8) . The mean planes of the nitro groups are twisted slightly from the benzene rings, forming dihedral angles in the range 2.3 (2)-8.6 (3) . The S-S bond length is 2.0458 (7) Å . Each S atom is essentially coplanar with the benzene ring to which it is attached, with deviations from the ring planes of 0.0163 (5) and 0.0538 (5) Å . In the crystal, molecules are linked through weak C-HÁ Á ÁO hydrogen bonds, forming a two-dimensional network parallel to (001).
The molecular structure of the title compound is shown in Fig and N4 respectively. In the crystal, weak C-H···O hydrogen bonds (Table 1) connect molecules to form R 3 3 (20) and R 3 3 (22) graph-set motifs (Bernstein et al., 1995) contained within two-dimensional corrugated sheets running parallel to (001) (Fig 2).
Experimental 1-Chloro-2,4-dinitrobenzene (2 g, 0.01 mol) was dissolved in 20 ml of DMSO. Thiourea (0.8 g, 0.01 mol) was also dissolved in 20 ml of DMSO. These two solutions were mixed together and stirred well for about 2 hours and then allowed to stand 303K. On standing, a crystalline yellow solid separated out. The yellow coloured crystals were filtered and dried. The solid obtained was ground well and washed repeatedly with water, alcohol and ether to remove unreacted 1-Chloro-2,4-dinitrobenzene (DNCB) and thiourea (TU  et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figure 1
The molecular structure of the title conpound showing 30% probability displacement ellipsoids.

Figure 2
Part of the crystal structure with hydrogen bonds shown as dashed lines. where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.44 e Å −3 Δρ min = −0.25 e Å −3 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.