Crystal structures and supra­molecular features of 99-dimethyl-37-di­aza­bicyclo­3.3.1nonane-2468-tetra­one 37-di­aza­spiro­bi­cyclo­3.3.1nonane-91′-cyclo­penta­ne-2468-tetra­one and 9-methyl-9-phenyl-37-di­aza­bicyclo­3.3.1nonane-2468-tetra­one di­methyl­formamide monosolvate

摘要

Compounds (I), C9H10N2O4, (II), C11H12N2O4, and (III), C14H12N2O4·C3H7NO represent 9,9-disubstituted-3,7-di­aza­bicyclo­[3.3.1]nonane-2,4,6,8-tetra­one deriv­atives with very similar mol­ecular geometries for the bicyclic framework: the dihedral angle between the planes of the imide groups is 74.87 (6), 73.86 (3) and 74.83 (6)° in (I)–(III), respectively. The dimethyl derivative (I) is positioned on a crystallographic twofold axis and its overall geometry deviates only slightly from idealized C 2v symmetry. The spiro-cyclo­pentane derivative (II) and the phen­yl/methyl analog (III) retain only inter­nal C s symmetry, which in the case of (II) coincides with crystallographic mirror symmetry. The cyclo­pentane moiety in (II) adopts an envelope conformation, with the spiro C atom deviating from the mean plane of the rest of the ring by 0.548 (2) Å. In compound (III), an N—H⋯O hydrogen bond is formed with the di­methyl­formamide solvent mol­ecule. In the crystal, both (I) and (II) form similar zigzag hydrogen-bonded ribbons through double inter­molecular N—H⋯O hydrogen bonds. However, whereas in (I) the ribbons are formed by two trans-arranged O=C—N—H amide fragments, the amide fragments are cis-positioned in (II). The formation of ribbons in (III) is apparently disrupted by participation of one of its N—H groups in hydrogen bonding with the solvent mol­ecule. As a result, the mol­ecules of (III) form zigzag chains rather than the ribbons through inter­molecular N—H⋯O hydrogen bonds. The crystal of (I) was a pseudo-merohedral twin.