Hl. Ammon et A. Bashirhashemi, STRUCTURE OF 2-METHOXYCARBONYL-1,4-DINITROCUBANE, Acta crystallographica. Section C, Crystal structure communications, 49, 1993, pp. 1641-1643
The title compound, methyl 2,7-dinitropentacyclo-[4.2 .0.0(2.5).0(3.8)
.0(4,7)]octane-1-carboxylate, is one of the few examples of cubanes wi
th substituents on adjacent C atoms. There are two enantiomeric molecu
les per asymmetric unit in a structure with a noncentrosymmetric space
group, P2(1)2(1)2. The molecules differ primarily in the conformation
s of the C-NO, groups adjacent to the methoxycarbonyl sustituents. The
1,2-disubstituted cubane C-C bonds average 1.564 angstrom, a typical
value for an unsubstituted cubane bond.