TRANSITION-METAL COMPLEXES OF 1,9-DISUBSTITUTED ADENINE-DERIVATIVES - SYNTHESIS AND STRUCTURE OF [BIS(ACETYLACETONATO) (NITRO) (1,9-DIMETHYLADENINIUM)COBALT(III)]-[BIS(ACETYLACETONATO) (DINITRO)COBALT(III)]

The synthesis and structure of the title complex are reported. The complex crystallizes in the triclinic system, space group PI, with [FORMULA OMMITED] Intensities for 4980 independent reflections were collected by counter methods on an automated diffractometer operating in the θ-2θ mode and employing Mo Kα monochromatized radiation. The structure was solved by standard heavy-atom Patterson methods. Full-matrix least-squares refinement has led to final R and weighted R values of 0.086 and 0.084, respectively. In the complex cation, the cobalt(III) atom is six-coordinate with two bidentate acetylacetonate ligands in equatorial positions and the N-bonded nitro group and the N(7)-bonded 1, 9-dimethyladeninium cation occupying axial positions. The two independent and centrosymmetric complex anions are also six-coordinate and the two nitro ligands are trans. The complex cation in addition to the Co(III)-N(7) bond has an asymmetric, bifurcated hydrogen-bond system involving one of the exocyclic amino hydrogen atoms of the purine ligand and two of the coordinated oxygen atoms of the acetylacetonate ligands. © 1979, American Chemical Society. All rights reserved.