3,7-DINITRONORADAMANTANE, C9H12N2O4, AND 3,7,9-TRINITRONORADAMANTANE,C9H11N3O(6)

The possible C-2v molecular symmetry for the dinitronoradamantane comp ound is not present; however, the carbon cages in each of the title co mpounds [3a,6a-dinitrooctahydro-2,5-methanopentalene and 3a,6a,7-trini trooctahydro-2,5-methanopentalene, respectively] have approximate C-2v symmetry. Although the C-C-N-O torsion angles of the nitro groups dif fer significantly from the 90 degrees required for C-2v molecular symm etry, approximate C-2 symmetry is maintained for both molecules in the asymmetric unit, Bond distances and angles are near expected values w ith the exception of the C3-C7 bond distance in both title compounds w hich averages 1.594(4) Angstrom.