名称:
Polynuclear Co(II) and Cu(II) complexes of tetraacetylethane: Cu<sup>II</sup><sub>2</sub>(dpa)<sub>2</sub>(tae)(O<sub>2</sub>CCF<sub>3</sub>)<sub>2</sub>, {[Cu<sup>II</sup><sub>2</sub>(dpa)<sub>2</sub>(tae)(4,4<i>'</i>-bipy)](O<sub>2</sub>CCF<sub>3</sub>)<sub>2</sub>}<I><sub>n</sub></I>, and [Co<sup>II</sup><sub>2</sub>(dpa)<sub>4</sub>(tae)](O<sub>2</sub>CCH<sub>3</sub>)<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>, dpa = 2,2<i>'</i>-dipyridylamine, tae = tetraacetylethane dianion
摘要:
The syntheses and structures of copper(II) and cobalt(II) complexes employing tetraacetylethane as the bridging ligand have been investigated. The reaction of Cu(O2CCF3)(2) with tetraacetylethane (tae) and 2,2'-dipyridylamine (dpa) yielded a dinuclear complex Cu-2(II)(dpa)(2)(tae)(O2CCF3)(2) (1), which has an extended hydrogen-bonded chain structure in the solid state. The reaction of 4,4'-dipyridyl (4,4'-bipy) with compound 1 resulted in the formation of a polymeric compound {[Cu-2(II)(dpa)(2)(tae)(4,4'-bipy)](O2CCF3)(2)}(n) (2), where the dinuclear unit is crosslinked by the 4,4'-dipyridyl ligand. The reaction of Co(O2CCH3)(2) with tetraacetylethane and 2,2'-dipyridylamine yielded a helical dinuclear complex [Co-2(II)(dpa)(4)(tae)](O2CCH3)(2)(H2O)(2) (3), which forms a hydrogen-bonded band architecture in the solid state. The three-dimensional structure of 3 has molecular sieve-like channels that host methanol molecules reversibly. While only either negligible or weak magnetic exchanges appear to be present in compounds 1 and 2, there appears to be a significant ferromagnetic exchange in 3, which is likely caused by orbital orthogonality of the Co(IT) ions, as supported by the crystal structure and EHMO calculations.