2,2′-(1,4-Phenylene)bis(propane-2,2-diyl) bis(benzodithioate)

The title compound, C26H26S4, shows a dihedral angle of 76.64 (15)° between the central and peripheral benzene rings. An inversion center is located at the centroid of the thiobenzoyl ring. In the crystal, weak C—H⋯S interactions form C(5) chains along [001]. There are no classical hydrogen bonds.

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: KJ2235).

Comment
The title compound belongs to a series of difunctional compounds that can be used to control the behavior of polymerization reactions to produce straight forward functional telechelic polymers in one pot (Patton et al., 2005;You et al., 2007;Pafiti et al., 2010). They are also used in radical polymerization with RAFT (reversible addition fragmentation chain transfer) reactions (Le et al., 1998). Telechelic polymers, defined as macromolecules with two reactive end groups, have been used for multiple purposes (Tasdelen et al., 2011) including block copolymer synthesis (Goethals, 1989). A perspective view of the molecule of the title compund, showing the atomic numbering scheme, is given in Fig. 1. Bond lengths and angles in the title compound have normal values (Allen et al., 1987). The molecular system has an inversion center and it is located at the center of the thiobenzoyl ring. The benzene rings bridged by the thio (C6-C7-S1-C8-C11) moiety are tilted to each other by a dihedral angle of 76.64 (15)°. The crystal packing shows no classical hydrogen bonds and it is stabilized by weak C-H···S intermolecular interactions, forming C(5) chains (Etter, 1990)

Experimental
The synthesis of the mentioned compound was accomplished following a procedure already reported (Le et al., 1998;Patton et al., 2005). A mixture of dithiobenzoic acid (5.00 g, 32.4 mmol) and 1,4-diisopropenylbenzene (2.44 g, 15.4 mmol) in carbon tetrachloride (40 ml) was heated at 348 K for 20 h. The volatiles were removed under reduced pressure and the oily product was mixed with 1:2 diethyl ether/hexane to isolate the product as a pink solid (40%).

Refinement
All H-atoms were placed in calculated positions [C-H= 0.95 Å for aromatic and C-H= 0.96 Å for methyl group] and refined with U iso (H) 1.2 and 1.5 times U eq of the parent atom, respectively.

Computing details
Data collection: COLLECT (Hooft, 2004); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 2012     Symmetry code: (i) x,-y + 1/2,z + 1/2. (ii) x,-y + 1/2,z -1/2. 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.