Polynuclear copper(II) carboxylates with 2,2'-bipyridine or 1,10-phenanthroline: Synthesis, characterization, X-ray structures and magnetism

摘要

[Cu2(phen)2(μ-O2CH)2(O2CH)2]_n (1) and [Cu6(bpy)6(μ-O2CC2H5)7(H2O)2)](PF6)5 · 2H2O (2) were synthesized and characterized by elemental analyses, electronic and EPR spectra and X-ray structure analyses. Compound 1 consists of four independent polymeric chains of dinuclear [Cu2(phen)2(μ-O2CH)2(O2CH)2] subunits with the asymmetric bidentate bridging formato groups linking Cu atoms in an anti-anti configuration. All Cu(II) ions are in a distorted square-pyramidal geometry. The hexanuclear copper(II) molecule of compound 2 is constructed from three different dinuclear units connected to each other via two syn-anti-μ3-η~1;η~2 carboxylato bridges. All copper(II) ions are in the distorted square-pyramidal geometry. Two terminal dinuclear units are similar in structure in which both Cu(II) ions are doubly bridged by the syn-syn carboxylato anions, while those of the central dinuclear entity are triply bridged by two μ3-η~1;η~2 carboxylato anions via monoatomic bridging fashion and one syn-syn carboxylato anion. The magnetic susceptibility (5-350 K) of compound 2 was measured and agree with a weak anti-ferromagnetic interaction between the Cu(II) centers.