1-{ [ 3-( Thiophen-2-yl )-4 , 5-dihydro-1 , 2-oxazol-5-yl ]-methyl }-2 , 3-dihydro-1 H-indole-2 , 3-dione

In the title compound, C16H12N2O3S, the indoline and thiophene rings are inclined to one another by 2.01 (2) . The isoxazole ring adopts an envelope conformation, with the methine C atom as the flap, and its mean plane is inclined to the thiophene and indoline ring mean planes by 19.78 (14) and 20.83 (12) , respectively. In the crystal, molecules are linked by C—H O hydrogen bonds involving the same acceptor atom, forming chains propagating along [010]. The chains are linked by further C—H O hydrogen bonds, forming slabs parallel to the (103) plane. The slabs are linked by offset – interactions [intercentroid distance = 3.792 (1) Å], forming a three-dimensional supramolecular structure.

In the title compound, C 16 H 12 N 2 O 3 S, the indoline and thiophene rings are inclined to one another by 2.01 (2) . The isoxazole ring adopts an envelope conformation, with the methine C atom as the flap, and its mean plane is inclined to the thiophene and indoline ring mean planes by 19.78 (14) and 20.83 (12) , respectively. In the crystal, molecules are linked by C-HÁ Á ÁO hydrogen bonds involving the same acceptor atom, forming chains propagating along [010]. The chains are linked by further C-HÁ Á ÁO hydrogen bonds, forming slabs parallel to the (103) plane. The slabs are linked by offsetinteractions [intercentroid distance = 3.792 (1) Å ], forming a three-dimensional supramolecular structure.
In the title compound, the indole ring system is almost planar as expected (r.m.s. deviation = 0.023 Å ). The dihedral angle between this plane and that of the thiophene ring (r.m.s. deviation = 0.012 Å ) is 2.01 (2) . Puckering analysis of the isoxazole ring [parameters Q(2) = 0.175 (2) Å and '(2) = 326.2 (8) ], indicates that it has an envelope data reports conformation with atom C10 as the flap. Its mean plane is inclined to the thiophene and indoline ring mean planes by 19.78 (14) and 20.83 (12) , respectively.

Synthesis and crystallization
To a solution of 0.4 g (2.18 mmol) of 1-allylindoline-2,3-dione and 0.5 g (4 mmol) of 2-thiophenecarboxaldehyde oxime in 15 ml of chloroform, were added 15 ml of bleach (24% weight) with a dropping funnel. The mixture was stirred for 4 h at 273 K. The solution was then concentrated to dryness under reduced pressure and the residue extracted with chloroform. The product isolated was chromatographed on a silica column (eluent: hexane/ethyl acetate 95:5 v/v). The solid obtained was crystallized from ethanol solution to give colourless rod-like crystals of the title compound.

Refinement
Crystal data, data collection and structure refinement details are summarized in Table 2. Table 1 Hydrogen-bond geometry (Å , ).

Figure 1
The molecular structure of the title compound, with the atom labelling and 40% probability displacement ellipsoids.

data-1
IUCrData (  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. The H-atoms of the thiophene moiety, although located in a difference map, did not refine satisfactorily and so were included as riding contributions in idealized positions.