Coordination properties of hypoxanthine: Crystal structures, thermal analysis, IR, and electronic spectral studies of CU(II)(hypoxanthine) SO4·H2O and of ME(II)(hypoxanthine)SO4·5H2O (Me(II) CO(II), Ni(II))

摘要: Three metal complexes of hypoxanthine, (6-hydroxypurine), have been synthesized in the form crystals suitable for x-ray crystallography. Aqua(μ-hypoxanthine)(μ-sulfato)copper(II), Cu(hyxa)SO4 · H2O, is monoclinic, space group P21, with a = 4.955(1), b 12.948(3), c 7.241(1) A, β 92.15°, Z 2. Pentaaqua(hypoxanthine)cobalt(II) sulfate, Co(hyxa)SO4 5H2O, triclinic, P1, 7.513(1), 12.959(2), 6.670(2) α 92.40(2), 90.02(2), γ 91.99(1)°, The crystal structures both were refined from diffractometer data to conventional R values 2.9% copper compound (1395 observed reflections, 172 variables) and 2.8% cobalt (6500 233 variables). In new coordination type unsubstituted hypoxanthine established: Hypoxanthine bridges two atoms via N(3) N(7), whereas N(9) N(1) are protonated. Infinite copper-hypoxanthine chains formed by through N(7') different ligand molecules. Copper(II) exhibits squarepyramidal nitrogen atoms, oxygen bridging sulfate groups one atom water molecule. 5H2O represents first example structurally characterized complex. It contains isolated octahedral [Co(hyxa)(H2O)5]2+ cations noncoordinating anions. binding site ofhypoxanthine at N(7); again nickel complex Ni(II)(hyxa)SO4 isostructural its analog.