6,7-Diphenyl-5-thia-7-aza-spiro-[2.6]nonan-8-one 5,5-dioxide

Abstract

The racemic mixture of the title compound, C₁₉H₁₉NO₃S, crystallizes in space group P with two homochiral mol-ecules in each asymmetric unit. The seven-membered ring in both mol-ecules is in a pucker-chair conformation. The extended structure exhibits C-H⋯O hydrogen bonds, of which two connect crystallographically independent mol-ecules to generate a chain propagating along the b-axis direction. One C-H grouping of the cyclo-propyl ring is in close contact with the phenyl ring of the neighboring independent mol-ecule in C-H⋯π type inter-actions with carbon atom-ring-centroid distances of 3.544 (5) and 3.596 (4) Å. Other inter-actions are of the parallel-reciprocal type, with the chiral carbon atom of one mol-ecule donating a proton to an oxygen atom of the sulfone group of a symmetry-related mol-ecule and vice-versa. Symmetry-related mol-ecular pairs also exhibit T-type inter-actions between aromatic rings with inter-planar angles of 74.2 (2) and 69.2 (2)° and inter-centroid distances of 4.965 (4) and 5.114 (4) Å.

Keywords: C—H⋯O; C—H⋯π; aromatic T-type stacking inter­actions; chair pucker; crystal structure.

Figure 1

The mol­ecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level. C—H⋯O inter­actions are shown as dashed lines.

Figure 2

Packing diagram viewing down a axis, showing C—H⋯O hydrogen bonds between mol­ecules.