The disordered molecular structure of (3aRS,7aRS)-1,3-dinitrosooctahydro-1H-benzimidazole

Abstract

The title compound, C(7)H(12)N(4)O(2), was obtained by nitrosation of the aminal cage (2R,7R,11S,16S)-1,8,10,17-tetraazapentacyclo[8.8.1.1(8,17).0(2,7).0(11,16)]icosane. The crystal structure is a racemic mixture of RR and SS enantiomers. The asymmetric unit contains two crystallographically independent half-molecules, one having two partially occupied conformers with refined occupancy factors of 0.747 (3) and 0.253 (3). The molecules sit across twofold axes. The unique molecules each form chains parallel to [001], with molecules connected by intermolecular C-H···O hydrogen bonds. The bonding between adjacent chains is weak. The analysis of eight different crystals confirmed the presence of disordered and nondisordered molecules in the same structure as a regular feature.