3,6,14,17-Tetramethoxy-22,23-diphenyl-1,10,12,21-tetraazahexacyclo[19.2.1.02,7.010,23.012,22.013,18]tetracosa-2(7),3,5,13(18),14,16-hexaene-11,24-dithione

The title compound, C36H34N4O4S2, is a thioglycoluril derivative, which bears two phenyl substituents on its convex face and two methoxy substituted o-xylylenes as sidewalls of the molecular clip. There is one half-molecule in the asymmetric unit: a crystallographic twofold axis generates the complete molecule. The non-planar seven-membered rings adopt chair conformations, while the two five-membered rings exhibit envelope conformations and make a dihedral angle of 68.46 (12)°. The O atoms of the methoxy groups are coplanar with the six-membered o-xylylene sidewalls.

There is one half-molecule in the asymmetric unit. The non-planar seven-membered rings adopt chair conformations, while the two five-membered rings have envelope conformation and the dihedral angle between them is 68.46°. The methoxy groups on sidewalls are coplanar with the six-membered o-xylylene sidewalls. The molecule contains three nonclassical intramolecular C-H···S, C-H···O and C-H···N hydrogen bonds, and its crystal structure is stabilized mostly by intermolecular C-H···π interactions (Table 1).

Experimental
The thioglycoluril was synthesized according to a literature procedure, see : Broan et al., (1989). Preparation of the title compound: A solution of thioglycoluril (326 mg, 1.00 mmol), paraformaldehyde (120 mg, 4.00 mmol) and 1,4-dimethoxybenzene (304 mg, 2.20 mmol) in TFA (5 ml) was stirred and heated at reflux for 6 h. After rotary evaporation the residue was chromatographed to yield the tile compound (521 mg, 0.80 mmol,80%). Crystals of (I) suitable for X-ray diffraction were grown by slow evaporation of a dichloromethane-methanol (1:2) solution of the title compound under 293 K.

Refinement
All H atoms were positioned in geometrically idealized positions and constrained to ride on their parent atoms, with C-H distances in the range 0.93-0.98 Å and Uĩso~(H) = 1.2U~eq~(C) or Uĩso~(H) = 1.5U~eq~(C). Fig. 1. A view of (I), showing the atom-labelling scheme, with displacement ellipsoids drawn at the 30% 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 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.