title: New discrete and polymeric supramolecular architectures derived from dinuclear (bis-beta-diketonato)copper(II) metallocycles.
abstract: New examples of adducts between di- (and, in one instance, tetra-) functional nitrogen ligands and planar 'platform-like' dinuclear copper(II) complexes, [Cu2L2], incorporating the 1,3-aryl linked bis-beta-diketonato bridging ligand 1,1'-(1,3-phenylene)-bis(4,4-dimethylpentane-1,3-dione) (H2L) have been synthesised. The X-ray structures of six adduct species are reported. The interaction of [Cu2(L)2] with the ditopic ligand aminopyrazine (apyz) yielded the sandwich-like tetranuclear species [(Cu2L2(apyz))2]. A variable-temperature magnetochemical investigation of this product indicated weak antiferromagnetic coupling between the (five-coordinate) copper centres, mediated by the 2-aminopyrazine linkers. An analogous structure, [(Cu2L2(dabco))2] (dabco=1,4-diazabicyclo[2.2.2]octane), was generated when dabco was substituted for aminopyrazine while use of 4,4'-dipyridyl sulfide (dps) and 4,4'-(1,3-xylylene)-bis(3,5-dimethylpyrazole) (xbp) as the ditopic 'spacer' ligands resulted in polymeric species of type [Cu2L2(dps)]n and [Cu2L2(xbp)]n, respectively. These latter species exist as one-dimensional chain structures in which copper(II) centres on different dinuclear platforms are linked in a 'zigzag' fashion. In contrast, with 2,2'-dipyridylamine (dpa) a discrete complex of type [Cu2L2(dpa)2] formed in which one potential pyridyl donor from each 2,2'-dipyridylamine ligand remains uncoordinated. The use of the potentially quadruply-bridging hexamethylenetetramine (hmt) ligand as the linker unit was found to give rise to an unusual two-dimensional polymeric motif of type [(Cu2(L2)2)3(hmt)2]n. The product takes the form of a (6,3) network, incorporating triply bridging hexamethylenetetramine units.
authors.affiliation: Centre for Heavy Metals Research, School of Chemistry, University of Sydney, NSW 2006, Australia.
authors.forename: Jack K
authors.initials: JK
authors.lastname: Clegg
authors.forename: Karsten
authors.initials: K
authors.lastname: Gloe
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Hayter
authors.forename: Olga
authors.initials: O
authors.lastname: Kataeva
authors.forename: Leonard F
authors.initials: LF
authors.lastname: Lindoy
authors.forename: Boujemaa
authors.initials: B
authors.lastname: Moubaraki
authors.forename: John C
authors.initials: JC
authors.lastname: McMurtrie
authors.forename: Keith S
authors.initials: KS
authors.lastname: Murray
authors.forename: David
authors.initials: D
authors.lastname: Schilter