5-Methyl-2,4-bis-(methyl-sulfan-yl)tricyclo-[6.2.1.0]undeca-4,9-diene-3,6-dione.

The structure analysis of the title compound, C(14)H(16)O(2)S(2), shows the SMe and H atoms of the bond linking the six-membered rings to be syn and also to be syn to the bridgehead -CH(2)- group. Each of the five-membered rings adopts an envelope conformation at the bridgehead -CH(2)- group. The dione-substituted ring adopts a folded conformation about the 1,4-C⋯C vector, with the ketone groups lying to one side. The cyclo-hexene ring adopts a boat conformation.

The structure analysis of the title compound, C 14 H 16 O 2 S 2 , shows the SMe and H atoms of the bond linking the sixmembered rings to be syn and also to be syn to the bridgehead -CH 2 -group. Each of the five-membered rings adopts an envelope conformation at the bridgehead -CH 2 -group. The dione-substituted ring adopts a folded conformation about the 1,4-CÁ Á ÁC vector, with the ketone groups lying to one side. The cyclohexene ring adopts a boat conformation.

Related literature
For background to reactions of toluquinone-cyclopentadiene Diels-Alder adducts epoxides with nucleophiles under heterogeneous conditions, see: von Richthofen et al. (2010). For conformational analysis, see: Cremer & Pople (1975 The structure of the title compound, (I), was investigated as a part of a study into the reactions of toluquinone-cyclopentadiene Diels-Alder adducts epoxides with nucleophiles under heterogeneous conditions (von Richthofen et al., 2010).
The most important feature of the molecular structure, Fig. 1, is the syn relationship between the bridgehead-C7, S1 and H6 atoms; the oxo groups and double bond of the hexene residue lie to the opposite side of the molecule to these atoms.

Experimental
The preparation and characterisation is as described in the literature (von Richthofen et al., 2010). The crystals were obtained by slow evaporation at 253 K from a 6:1 solution of n-hexane:ethyl acetate.

Refinement
The H atoms were geometrically placed (C-H = 0.93-0.98 Å) and refined as riding with U iso (H) = 1.2-1.5U eq (C). Fig. 1. The molecular structure of (I) showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level.

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 supplementary materials sup-3 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 > 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.