3-(1,3-Dithiolan-2-ylidene)-1-(4-methoxyphenyl)pyridine-2,4(1H,3H)-dione

In the title compound, C15H13NO3S2, the dithiolane ring adopts a twisted conformation. The molecule exhibits a V-shaped conformation, with a dihedral angle of 79.05 (7)° between the benzene ring and the pyridine ring. In the crystal, C—H⋯O interactions are observed.

In the title compound, C 15 H 13 NO 3 S 2 , the dithiolane ring adopts a twisted conformation. The molecule exhibits a Vshaped conformation, with a dihedral angle of 79.05 (7) between the benzene ring and the pyridine ring. In the crystal, C-HÁ Á ÁO interactions are observed.

Related literature
For the synthesis, see: Li et al. (2008). For background to Nsubstituted pyridine compounds and their potential use in medicinal chemistry, see: Kim et al. (2008); Zhu et al. (2006) Experimental Crystal data  Table 1 Hydrogen-bond geometry (Å , ).
is presented here. The molecular structure of the title compound, together with the atom-numbering scheme, is illustrated in Fig.1. Selected bond lengths and angles are given in Table 1. The molecule exhibits a V-shaped conformation in the crystal with a dihedral angle of 79.05 (7)° between the benzene ring and the pyridine ring. The dithiolane ring has a twisted conformation.

Experimental
The title compound was synthesized according to the literature (Li et al., 2008). It was dissolved in ethyl acetate at room temperature and hexane was added. The solution was kept at room temperature in a sealed flask for a few days to give single crystals suitable for single-crystal X-ray analysis.

Refinement
All H atoms bound to C atoms were generated geometrically and refined as riding atoms with C-H= 0.93Å for aromatic H , 0.96Å for CH 3 groups, 0.97Å for CH 2 groups, and with U iso (H) = 1.5U eq (C) for CH 3 groups and U iso (H) = 1.2U eq (C) for all the other groups. Fig. 1. Molecular structure of the title compound with displacement ellipsoids drawn at the 30% probability level for non-H atoms.

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.