Shi-Ping Yan

Synthesis, X-ray structure and magnetic properties of trinuclear copper(II) tridentate Schiff base complexes containing a partial cubane Cu3O4 core

Abstract Two copper(II) complexes with tridentate Schiff bases AE and SE, which are condensed from N,N-dimethylethylenediamine and acetylacetone or salicylaldehyde, respectively, have been synthesized, characterized by X-ray structural analysis, magnetic measurement, IR and UV spectra. Both of the complexes contain a partial cubane Cu3O4 core consisting of [Cu(AE)] or [Cu(SE)], nonbonded ClO4xa0− anions and water molecules. The two complexes comprise three [Cu(AE)] or [Cu(SE)] subunits, respectively, which are interconnected through two types of oxygen bridges afforded by the oxygen atoms of the ligands and the central OH− group. The average Cuue5f8O distances involving hydroxy OH− are 2.053 A in complex 1 and 2.078 A in complex 2. Complex 1 exhibits an antiferromagnetic interactions between the copper ions with J=−2.40 cm−1 and g=2.038. Complex 2 exhibits a ferromagnetic interaction between the copper ions with J=7.83 cm−1 and g=2.02.

Heterobinuclear copper(II)–nickel(II) complexes of macrocyclic oxamide with diamines and tetraazacyclam as blocking ligands: synthesis, crystal structure and magnetic properties

Three novel oxamido-bridged heterobinuclear copper(II)–nickel(II) complexes derived from macrocylic oxamido compound with diamines and tetraazacyclam as blocking ligands were synthesized and characterized by IR, ESR and electronic spectra. Their formula is [Cu(L)Ni(en) 2 ](ClO 4 ) 2 ·0.5C 2 H 5 OH·H 2 O ( 1 ), [Cu(L)Ni(tmd) 2 ](ClO 4 ) 2 ·4H 2 O ( 2 ) and [Cu(L)Ni( rac -cth)](ClO 4 ) 2 ·CH 3 OH ( 3 ), where L=1,4,8,11-tetraazacyclotradecanne-2,3-dione, en=1,2-diaminoethande, tmd=1,3-diaminopropane and rac -cth is rac -5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane. The crystal structures of the three complexes have been determined. The structures consist of binuclear units in which the copper(II) ion is in a square-planar environment and linked to the nickel(II) ion via the exo - cis oxygen atoms of the oxamido macrocyclic ligand, with Cu⋯Ni separations of 5.311 ( 1 ), 5.420 ( 2 ) and 5.307 A ( 3 ), respectively. The temperature dependence of the magnetic susceptibility for 1 , 2 and 3 was analyzed by means of the Hamiltonian Ĥ =−2 JŜ Ni Ŝ Cu , leading to J =−52.8, −45.7 and −56.9 cm −1 for 1 , 2 and 3 , respectively.

Synthesis, crystal structure and magnetic properties of a new dialkoxo-bridged diiron(III) complex

Abstract A new dialkoxo-bridged diiron(III) complex, [Fe2(N3)2(L)2](ClO4)2 (1) [HL=bis(benzimidazol-2-ylmethyl)(2-hydroxyethyl)amine], was synthesized and characterized. According to X-ray crystallographic studies on the solvated species 1·2C2H5OH, each Fe(III) ion lies in a highly distorted octahedral environment, and two Fe(III) ions are bridged by the ethoxyl oxygens from two L ligands. Cryomagnetic analyses indicated a moderate antiferromagnetic interaction between the high-spin Fe(III) ions, with J=−21.3 cm−1.

A new μ1,5-dicyanamide bridged cyclic tetranuclear copper (II) complex with 1,5,9-triazacycledodecane ligands: structure, ESR spectroscopic and magnetic properties

Abstract The tetranuclear complex [Cu2L2(dca)2(ClO4)2]2 (1) (Lxa0=xa01,5,9-triazacyclododecane, dcaxa0=xa0dicyanamide [N(CN)2]−) has been synthesized and its crystal structure, ESR spectra and magnetic properties determined. The complex contains a tetranuclear copper (II) moiety in which two dimeric units are bridged by two dca ligands. In each dimeric moiety the two copper (II) ions are bridged by one μ1,5-dicyanamide ligand. Magnetic susceptibilities for the complex in the solid state are measured over the temperature range 4–300 K. The complex shows a weak antiferromagnetic coupling with a best fit J value −0.436 cm−1. The μ1,5-dicyanamide bridges are the principal pathway for the super-exchange interaction and the weak antiferromagnetic coupling of the complex is interpreted in term of the μ1,5-dicyanamide ligand behavior as a poor magnetic mediator.

Synthesis, crystal structures and luminescent properties of two supramolecular assemblies containing [Au(CN)2]- building block

Two self-assembled supramolecular architectures {{MnH2O(Phen)2[Au(CN)2]}[Au(CN)2]·0.5C2H5OH·0.5H2O}n n (phen = 1, 10-phenanthroline) n (1) and [C6H13N4][Au(CN)2]·H2O(C6H13N4 n = 4-amide-3, 5-diethyl-1, 2, 4-triazole cation) n (2) have been synthesized and structurally characterized. X-ray crystallography revealed a three-dimensional structure of 1 formed by the incorporation of coordinative linkage, aurophilic, hydrogen-bonding and π–π interactions. The 2D structure of 2 is formed by aurophilic and hydrogen-bonding interactions. Both the solid phases and aqueous solutions of 1 and 2 display interesting luminescence at room temperature.

Heterobinuclear copper(II)–manganese(II) complexes behaving as three-dimensional supramolecular networks via both macrocyclic oxamido-bridges and hydrogen bonds

Two novel oxamido-bridged heterobinuclear copper(II)–manganese(II) complexes derived from macrocylic oxamido compounds incorporating different blocking ligands were synthesized and characterized by IR and electronic spectroscopy. They are of formula [Cu(L)Mn(phen)2](ClO4)2·1.5H2O (1) and [Cu(L)Mn(ntb)](ClO4)2·H2O (2), where L = 1,4,8,11-tetraazacyclotetradecane-2,3-dione, phen = 1,10-phenanthroline and ntb = tris(2-benzimidazolylmethyl)amine. The crystal structures of the two complexes have been determined and they consist of binuclear units in which the copper(II) ion is in a square-planar environment and linked to the manganese(II) ion via the exo–cis oxygen atoms of the oxamido macrocyclic ligand, nwith Cu⋯Mn separations of 5.421 (1) and 5.486 A (2), respectively. The packing of the molecules along the a orientation in 2 results in open channels, which were extended into a three-dimensional hydrogen-bonded supramolecular network. The temperature dependence of the magnetic susceptibility for 1 and 2 were analyzed by means of the Hamiltonian, Ĥ n= n−2JŜMnŜCu, leading to J n= n−14.2 and −14.7 cm−1 for 1 and 2, respectively.

Synthesis, crystal structure, spectroscopic and magnetic properties of [Cu(dien)2][Ni(CN)4]

A new complex, [Cu(dien)2][Ni(CN)4] (1) [dienu2009=u2009diethylenetriamine] has been obtained by the reaction of Cu(ClO4)2·6H2O, diethylenetriamine and K2[Ni(CN)4] in water, and has been characterized spectroscopically. The crystal structure of 1 has been determined. In the complex, two tridentate dien ligands are bonded to the copper(II) ion in a distorted octahedral arrangement and the anion remains outside the coordination sphere.