1-Methyl-2-({[(2-methylphenyl)methyl]disulfanyl}methyl)benzene

In the title disulfide, C16H18S2, the molecule is twisted about the central S—S bond [the C—S—S—C torsion angle = 93.24 (7)°] and the dihedral angle between the benzene rings is 72.84 (7)°, indicating an almost orthogonal relationship; the methyl groups are orientated to the same side of the molecule. The crystal packing features C—H⋯.π interactions which consolidate a three-dimensional architecture.

In the title disulfide, C 16 H 18 S 2 , the molecule is twisted about the central S-S bond [the C-S-S-C torsion angle = 93.24 (7) ] and the dihedral angle between the benzene rings is 72.84 (7) , indicating an almost orthogonal relationship; the methyl groups are orientated to the same side of the molecule. The crystal packing features C-HÁ Á Á. interactions which consolidate a three-dimensional architecture.

Crouse and Edward R. T. Tiekink Comment
Our interest in investigating the coordination properties of ligands containing the H-N-C═S moiety and our desire to expand the study of this class of biologically important compounds has lead us to synthesize series of related ligands (Tarafder et al., 2000;Crouse et al., 2004;Ravoof et al., 2010). The title compound, [(2-methyl)benzyl]disulfide, (I), was obtained during the attempt to prepare the phenyl hydrazine analogue of S-benzyldithiocarbazate.
In (I), Fig. 1, the molecule is twisted about the central S1-S2 bond as seen in the value of the C1-S1-S2-C9 torsion angle of 93.24 (7) Å. The dihedral between the benzene rings is 72.84 (7)°, indicating an almost orthogonal relationship, and the methyl groups are orientated to the same side of the molecule. The overall conformation in (I) contrasts that found in the parent compound, bis(benzyl)disulfide (van Dijk & Visser, 1971), which adopts an open conformation with both phenyl rings directed away from the sulfur atoms. In (I), the S1-bound benzyl is directed away having an anti disposition [the S2-S1-C1-C2 torsion angle is 176.23 (9)°] whereas the S2-bound benzyl residue in bis(benzyl)disulfide (van Dijk & Visser, 1971) has a syn conformation [S1-C1-C2-C7 = 91.90 (14)°].

Experimental
[(2-Methyl)benzyl]disulfide was isolated as a by-product from the synthesis of the phenylhydrazine analog of S-benzyldithiocarbazate (Tarafder et al., 2000). Potassium hydroxide (0.2 mol, 11.2 g) was completely dissolved in absolute ethanol (70 ml) and phenylhydrazine (0.2 mol, 21.6 g) was added to the solution cooled in an ice-salt bath producing a dark-yellow solution. Carbon disulfide (0.2 mol, 15.2 g) was added drop-wise with constant stirring over one hour. 2-Methylbenzyl chloride (0.1 mol, 13.2 ml) was then added drop-wise with vigorous stirring. The temperature of reaction was maintained below 278 K. The high yield yellow-white product was filtered and dried in a dessicator over anhydrous silica gel, dissolved in absolute ethanol and kept in a freezer. A few colourless blocks were harvested on the third day and washed with cold n-hexane.

Refinement
Carbon-bound H-atoms were placed in calculated positions (C-H = 0.95 to 0.99 Å) and were included in the refinement in the riding model approximation with U iso (H) set to 1.2 to 1.5U equiv (C).

Figure 1
The molecular structure of (I) showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level.   Special details Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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 )
x y z U iso */U eq S1 0.19303 (