Crystal and molecular structure of bis(quinoxaline)-2,2′,3,3′-disulfide, C₁₆H₈N₄S₂

Abstract

The crystal and molecular structure of bis(quinoxaline)-2,2′3,3′-disulfide, C₁₆H₈N₄S₂, was determined by direct methods and refined by least-squares methods, using 823 reflections collected with a two-circle Weissenberg diffractometer, including anisotropic temperature factors for nonhydrogen atoms to a finalR of 0.104. The crystals are monoclinic prismatic: space groupP2₁/a,a = 18.98(2),b = 9.27(2),c = 3.89(1) Å, β = 100.3 °(1),Z = 2. The structure consists of layers of molecules staggered along thec axis. The molecule is centrosymmetric, and makes an acute angle of 36.9 ° with theab plane; it is planar within an rms atom deviation of 0.02 Å. The S-C (1.752–1.760 Å) distances are normal for a S-C (sp²) bond. The N-C bonds (1.372–1.381 Å) adjacent to the benzene ring are longer than the N-C bonds (1.318–1.322 Å) adjacent to the central C₄S₂ ring.