(E)-3-Dimethylamino-1-(1,3-thiazol-2-yl)prop-2-en-1-one

In the title compound, C8H10N2OS, the 3-(dimethylamino)prop-2-en-1-one unit is approximately planar [give r.m.s. deviation] and the mean plane through the seven non-H atoms makes a dihedral angle of 8.88 (3)° with the thiazole ring. The carbonyl and ring C=N double bonds adjacent to the carbonyl group are trans [N—C—C—O = 172.31 (15) °], while the conformation of the carbonyl and propene double bonds is cis [O—C—C—C = 2.2 (2)°]. In the crystal, short C—H⋯N and C—H⋯O interactions together with C—H⋯π interactions generate a three-dimensional network.

In the title compound, C 8 H 10 N 2 OS, the 3-(dimethylamino)prop-2-en-1-one unit is approximately planar [give r.m.s. deviation] and the mean plane through the seven non-H atoms makes a dihedral angle of 8.88 (3) with the thiazole ring. The carbonyl and ring C N double bonds adjacent to the carbonyl group are trans [N-C-C-O = 172.31 (15) ], while the conformation of the carbonyl and propene double bonds is cis [O-C-C-C = 2.2 (2) ]. In the crystal, short C-HÁ Á ÁN and C-HÁ Á ÁO interactions together with C-HÁ Á Á interactions generate a three-dimensional network.

D-HÁ
Data collection: CrysAlis PRO (Oxford Diffraction, 2006); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009) and Mercury (Macrae et al., 2006); software used to prepare material for publication: OLEX2. Enaminone derivatives are of great importance in organic synthesis (Zeng et al., 2010). The title compound is one of the key intermediates in our synthetic investigations on compounds active against of anti-hepatocellular carcinoma and cancers. We report here its crystal structure.

Experimental
A solution of 6.36 g (50.0 mmol) of 1-thiazol-2-yl-ethanone in 16.03 ml (17.87 g,150.0 mmol) of DMF-DMA (dimethoxy-N,N-dimethylmethanamine) was stirred for 24 h at 114°C. The solvent was evaporated and the title compound was recrystallized from ethanol. Yield: 6.83 g (75%). Crystals suitable for X-ray analysis were obtained by slow evaporation from a solution of ethyl acetate.

Refinement
All H atoms were positioned geometrically (for methyl, C-H = 0.98 Å; for the other H atoms, C-H = 0.95 Å) and refined using a riding model, withU iso (H) = kU eq (C), where k = 1.5 for methyl and 1.2 for all other H atoms.

Figure 2
A crystal packing diagram of the title compound. The dashed lines represent C-H···π interactions. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 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.