1-(5-Benzylsulfanyl-2,2-dimethyl-2,3-dihydro-1,3,4-thiadiazol-3-yl)-2,2-dimethylpropan-1-one

In the title compound, C16H22N2OS2, the S atom of the thiadiazole ring and the attached methyl groups are disordered over two orientations with a refined site-occupancy ratio of 0.641 (11):0.359 (11). The thiadiazole ring is in a twist conformation in both disorder components. The mean plane through the thiadiazole ring makes dihedral angles of 77.39 (8) (major component) and 67.45 (11)° (minor component) with the benzene ring. Intramolecular C—H⋯N interactions generate two S(6) ring motifs. In the crystal, molecules are linked by C—H⋯O hydrogen bonds into zigzag chains parallel to the b axis.

In the title compound, C 16 H 22 N 2 OS 2 , the S atom of the thiadiazole ring and the attached methyl groups are disordered over two orientations with a refined site-occupancy ratio of 0.641 (11):0.359 (11). The thiadiazole ring is in a twist conformation in both disorder components. The mean plane through the thiadiazole ring makes dihedral angles of 77.39 (8) (major component) and 67.45 (11) (minor component) with the benzene ring. Intramolecular C-HÁ Á ÁN interactions generate two S(6) ring motifs. In the crystal, molecules are linked by C-HÁ Á ÁO hydrogen bonds into zigzag chains parallel to the b axis.

Related literature
For background to the pharmacological properties of thiadiazole derivatives, see: Noolvi et al. (2011);Yusuf et al. (2008). For a related structure, see: Fun et al. (2011). For hydrogenbond motifs, see: Bernstein et al. (1995). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986). For ring conformations, see: Cremer & Pople (1975 Table 1 Hydrogen-bond geometry (Å , ).   et al., 2008). The title compound is one of these thiadiazole derivatives, and its crystal structure is reported herein.

Refinement
The S atom of the thiadiazole ring and the attached dimethyl groups (C10/C10X) and C11/C11X) are disordered over two orientations with a refined site-occupancy ratio of 0.641 (11):0.359 (11). All H atoms were positioned geometrically [C-H = 0.95-0.99 Å] and refined using a riding model with U iso (H) = 1.2 or 1.5 U eq (C). A rotating group model was applied to the methyl groups.

Figure 1
The molecular structure of the title compound with 30% probability displacement ellipsoids. Dashed lines indicate intramolecular hydrogen bonds. Bonds involving the minor component of the disorder are shown as empty sticks.

Figure 2
The crystal packing of the title compound viewed along the c axis. The H atoms not involved in the intermolecular interactions (dashed lines) are omitted for clarity. Only major disordered components are shown. 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq Occ.