Crystal and molecular structure of dimorpholinotetrasulphane

Abstract

The tetrasulphane S₄(NC₄H₈O)₂ crystallizes in the tetragonal space group l4₁/a(no. 88) with a=b= 12.812(1), c= 16.733(2)Å, and Z= 8. The structure has been determined by X-ray diffraction from Mo-K_α diffractometer data and refined by full-matrix least squares to R 0.045 for 948 observed reflections. The molecules lie across crystallographic two-fold axes. The N–S–S–S–S–N chains occur in the trans-trans form, with N–S 1.668(3), S–S (terminal) 2.061(2), S–S (central) 2.078(3)Å, N–S–S 109.1(2), S–S–S 105.8(1)°, NSS–SSS 90.3 and SSS–SSS 79.9°. The morpholine groups occur in the chair form, with N–S equatorial. The S–S bonds alternate only slightly in length along the chain, like the Se–Se bonds in the isomorphous tetraselane analogue.