3,9-Diisopropyl-2,4,8,10-tetrathiaspiro[5.5]undecane

The molecule of the title compound, C13H24S4, has C2 symmetry and it crystallizes as a racemate. The structure displays two six-membered rings exhibiting chair conformations, with the isopropyl substituents in equatorial positions. In the crystal structure, weak intermolecular C—H⋯S interactions are observed, leading to a channel-like arrangement along the c axis.

The molecule of the title compound, C 13 H 24 S 4 , has C2 symmetry and it crystallizes as a racemate. The structure displays two six-membered rings exhibiting chair conformations, with the isopropyl substituents in equatorial positions. In the crystal structure, weak intermolecular C-HÁ Á ÁS interactions are observed, leading to a channel-like arrangement along the c axis.

Experimental
Due to the space arrangement there are differences between positions 2, 4 and 2', 4'. Due to these differencies positions 4 and 4' which are oriented towards the other 1,3-dithiane ring are named methylene inside, while the other two CH 2 groups (positions 2 and 2') are oriented in opposite direction and they are named methylene outside groups.
These weak interactions stabilize the lattice and form a three-dimensional network as a channel-like arrangement along the c axis.

Experimental
The synthesis of I has been described elsewhere (Gâz et al., 2008). Crystal were obtained from dichloromethane, by slow evaporation at room temperature.

Refinement
All hydrogen atoms were placed in calculated positions using a riding model, with C-H = 0.93-0.97 Å and with U iso = 1.5U eq (C) for H. The methyl groups were allowed to rotate but not to tip. Fig. 1. ORTEP digram of the title compound, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.   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 Rfactors(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.