3-(2,2-Dioxo-3,4-dihydrobenzo[e][1,2,3]oxathiazin-4-yl)-3-fluoro-1-phenylindolin-2-one

The title compound contains two chiral carbon centres. It has monoclinic (P21/c) symmetry. The structure displays N—H⋯O hydrogen bonding.


Structure description
The incorporation of one or more fluorine atoms into an organic molecule can result in improved thermal/metabolic stability, bioactivity and lipophilicity (Purser et al., 2008). In this context, the -fluoroamine motif is an important structural feature and has been found in a number of drug candidates (Zhao et al., 2019). Consequently, the synthesis of chiral molecules with a fluorinated carbon center has attracted recent attention (Shang et al., 2015;Chen et al., 2017;Paladhi et al., 2017;Zheng et al., 2018). As part of our work in this area, we now describe the synthesis and structure of the title compound (Fig. 1).
The geometric parameters do not show any unusual features. In the crystal, molecules are connected by pairwise N-HÁ Á ÁO hydrogen bonds (Table 1, Fig. 2) to generate centrosymmetric R 2 2 (12) loops.

Refinement
Crystal data, data collection and structure refinement details are summarized in Table 2. The disordered sulfonate group was treated using a PART command in the refinement. The occupancy factors were restrained to sum to unity. The refined occupancy ratio is 0.933 (4):0.067 (4). Atomic displacement parameters of S1 and O3 were restrained using a DELU command.

Figure 1
The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. Only the major disorder component is shown

3-(2,2-Dioxo-3,4-dihydrobenzo[e][1,2,3]oxathiazin-4-yl)-3-fluoro-1-phenylindolin-2-one
Crystal data  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. The position of H(2) atom was found from the diagram of differential Fourier synthesis.