Second-sphere coordination of ‘star’-shaped hexakis(N-pyridin-4-one)benzene (HPOB) with hexakis(methanol)nickel(II) nitrate; unusual (NO3−)(HPOB)(NO3−) π-stacked ‘sandwiching’
摘要:
It is shown by X-ray studies that the compound Ni(HPOB)(NO3)(2)(MeOH)(9) [where HPOB = hexaxis(N-pyridin-4-one)benzene] contains [Ni(MeOH)(6)](2+) cations hydrogen-bonded to the oxygen atoms of the pyridone units in HPOB, with the resulting six-connectivity at both metal and HPOB producing a three-dimensional network array essentially topologically equivalent to the alpha-Po structure. The pyridone rings in the HPOB molecules are arranged orthogonally to the central C-6 ring and the nitrate anions form an unusual (NO3)(HPOB)(NO3-) 'sandwich' by a combination of pi-stacking and C-H...O hydrogen bonds. (C) 2002 Elsevier Science B.V. All rights reserved.