Crystal structure ofrac-2,3-diphenyl-2,3,5,6-tetrahydro-4H-1,3-thiazin-4-one 1-oxide

Abstract

In the title compound, C16H15NO2S [alternative name:rac-2,3-diphenyl-1,3-thiazinan-4-one 1-oxide], the thiazine ring exhibits an envelope conformation, with the S atom forming the flap. The sulfoxide O atom is in a pseudo-axial position on the thiazine ring and istransto the phenyl group on C-2. The phenyl rings form a dihedral angle of 89.47 (19)°. In this racemate crystal, homochiral molecules form slabs parallel to (010) of thicknessb/2 which then stack with alternating chirality in theb-axis direction. The stacking is aided by edge-to-face interactions between the phenyl rings of racemic molecules. Within each of the single-enantiomer slabs, the molecules are held by C—H...O-type interactions, with an H...O distance of 2.30 Å, forming infinite chains along thec-axis direction, as well by the edge-to-face interactions between phenyl rings of neighboring molecules in thea-axis direction.