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Three new heteronuclear [FeW 9 O 34 ]-based sandwich-type complexes [Fe III 2 Mn II 2 (H 2 O) 2 (FeW 9 O 34 ) 2 ] 12− ( 1 ), [Fe III 2 Mn III 2 (H 2 O) 2 (FeW 9 O 34 ) 2 ] 10− ( 2 ) and [Fe III 2 Ni II 2 (H 2 O) 2 (FeW 9 O 34 ) 2 ] 12− ( 3 ) have been synthesized by an innovative method of pH-controllable degradation in aqueous solution, in which the [FeW 12 O 40 ] 5− precursor could be predominantly degraded into the trivacant [FeW 9 O 34 ] 11− anion. The active ligand of trivacant [FeW 9 O 34 ] 11− anion can catch in situ the mixed transition metal ions to conduce a directed coordination assembly reaction. These three heteronuclear complexes have been characterized by elemental analysis, single-crystal and powder X-ray diffraction analyses, IR spectra, UV–vis spectra, and thermal gravimetric analysis, cyclic voltammetry, magnetic properties, and thermal gravimetric analysis. Complexes 1 and 3 exhibit obvious catalytic activities for electrocatalytic reduction of nitrate. Compared with 1 , the magnetic property of 2 shows a remarkable change by only a conversion of Mn(II) into Mn(III), so that a strong ferromagnetic interaction occurs in 2 . [ABSTRACT FROM AUTHOR]

Two unique heteronuclear Schiff base complexes of Cu(II), [{Cu(L)Na(ClO 4 )} 2 (μ-H 2 L)] ( 1 ) and Ni(II), [{Ni(L)Na(BF 4 )} 2 (μ-H 2 L)] ( 2 ) were synthesized and characterized by different spectroscopic methods as well as X-ray crystallography. The Schiff base ligand (H 2 L) was synthesized from the condensation meso-1,2-diphenyl-1,2-ethylenediamine with 3-methoxysalicylaldehyde. The 3d metal ions in these complexes have been accommodated by the inner N 2 O 2 compartment of the Schiff base ligand, while the O 2 O′ 2 outer compartment has accommodated the Na(I) ion (O and O′ denote the phenolic and methoxy oxygen atoms, respectively). Besides, a Schiff base ligand has doubly bridged the M(II)/Na(I) moieties via the (OO′) 2 coordination mode. This mode of bidentate action of a potentially tetradentate Schiff base ligand is very rare and has been observed for the first time in such 3d-ns complexes. The in vitro antibacterial activity of the Schiff base ligand and the complexes ( 1 ) and ( 2 ) were tested against human pathogenic bacteria such as Bacillus subtilis (Gram positive); Staphylococcus aureus (Gram positive); Salmonella typhi (Gram negative); and Escherichia coli (Gram negative). The results showed that these new hetero-polynuclear complexes had moderate antibacterial activity against both Gram type bacteria. [ABSTRACT FROM AUTHOR]

Two new heteronuclear Nickel(II)/Sodium(I) complexes of a side-off compartmental Schiff base ligand were synthesized and characterized by spectroscopic methods. Crystal structures of both of the complexes were also obtained. The Schiff base ligand was synthesized from the condensation of meso-1,2-diphenyl-1,2-ethylenediamine with 2-hydroxy-3-methoxybenzaldehyde. In both of the complexes the Ni(II) ion is coordinated to the inner N 2 O 2 coordination sphere with square-planar geometry and the Na(I) ion is coordinated to the outer O 2 O 2 ′ coordination sphere. In Complex ( 1 ) with general formula [Ni(L)Na(CH 3 OH)(ClO 4 )] the sodium ion is seven coordinated while in ( 2 ) with general formula [{Ni(L)Na(OH 2 )} 2 (μ-Ni(CN) 4 )] the sodium ion is six coordinated. Intermolecular interactions in two studied complexes were analyzed using 3D Hirshfeld surfaces and corresponding 2D fingerprint plots. This analysis showed that the H … H and C … H/H … C contacts for both structures (altogether 67.5% of total Hirshfeld surface area for ( 1 ) and 77.6% for ( 2 )) and the O … H/H … O (24.2%) for ( 1 ) and the N … H/H … N (8.1%) contacts for ( 2 ) were the characteristic intermolecular contacts in the related crystal structures. [ABSTRACT FROM AUTHOR]

A new hetero trinuclear manganese(III)-iron(II) complex, [Mn(salen)(H2O)] 2[Fe(CN)6], in which salen is the dianionic form of N,N'-bis(5-methylsalicylidene)-1,2-diaminoethane, has been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination. The crystal of the complex is monoclinic: space group P21/c, a = 10.768(2), b = 14.248(3), c = 15.222(3) Å, β = 95.394(2)º, V = 2325.0(8) ų, Z = 2, R1 = 0.0754, wR2 = 0.2366. The bis-Schiff base ligand coordinates to the Mn atom through phenolate O and imine N atoms. Each Mn atom in the complex is in octahedral coordination, with the equatorial donor atoms come from the Schiff base ligand, and with the axial donor atoms come from a water O atom and a cyanide N atom. The effects of the complex on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were studied. [ABSTRACT FROM AUTHOR]

Highlights: [•] Nine new heterometallic complexes containing copper(II) and silver(I). [•] The second examples of 3d–silver(I) compounds from acyclic Schiff base ligands. [•] Two compounds are coordination polymers due to Ag–π (arene; η1-/η2-/η3-) bonds.. [•] Six dimer-of-dinuclear systems due to silver(I)⋯silver(I) interaction. [•] CSD survey reveals some definitely significant aspects. [Copyright &y& Elsevier]

The work in this report presents the syntheses, characterization, crystal structures and electronic spectra of the six heteronuclear complexes [CuIIL1NaI(μ-BF4)2NaIL1CuII]·2CH3COCH3 (1), [CuIIL1NaI(NO3)(MeOH)] (2), [CuIIL1ZnII(H2O)2L1CuII](ClO4)2 (3), [CuII(MeOH)L1ZnIICl2] (4), [CuIIL1CdII(H2O)(MeOH)2](ClO4)2 (5) and [CuIIL1CdIICl2(MeOH)]·[CuII(MeOH)L1CdIICl2] (6), where H2L1 is N,N′-ethylenebis(3-methoxysalicylaldimine). The crystal systems and space groups are as follows: 1 and 2, triclinic, ; 3 and 6, monoclinic, P21/c; 4, orthorhombic, P212121; 5, monoclinic, C2/c. While the N(imine)2O(phenoxo)2 compartment accommodates the copper(II) center, the larger and open O(phenoxo)2O(methoxy)2 compartment interacts with the second metal ion. Compounds 2, 4 and 5 are diphenoxo-bridged dinuclear systems, compound 3 is a trinuclear system in which the two CuIIZnII pairs are monophenoxo-bridged, compound 1 is a tetranuclear system in which two diphenoxo-bridged CuIINaI units are interlinked by two tetrafluoroborate moieties, and compound 6 is a [2×1+2×1] co-crystal of two dinuclear CuIICdII units. The solid state electronic spectra of compounds 1–6 and also the mononuclear compound [CuIIL1(H2O)] have been recorded in the range 400–800nm. While correlating the d–d band position with the structural parameters and a previously proposed correlation, some inconsistency has been found, indicating that this area should be explored further. [ABSTRACT FROM AUTHOR]

Heteronuclear complexes containing oxorhenium(V), with Fe(III), Co(II), Ni(II), Cu(II), Cd(II) and UO 2 (VI) ions were prepared by the reaction of the complex ligands [ReO(HL 1 )(PPh 3 )(OH 2 )Cl]Cl ( a ) and/or [ReO(H 2 L 2 )(PPh 3 )(OH 2 )Cl]Cl ( b ), where H 2 L 1 = 1-(2-hydroxyphenyl)butane-1,3-dione-3-(5,6-diphenyl-1,2,4-triazine-3-ylhydrazone) and H 3 L 2 = 1-(2-hydroxyphenyl)butane-1,3-dione-3-(1 H -benzimidazol-2-ylhydrazone), with transition and actinide salts. Heterodinuclear complexes of ReO(V) with Fe(III), Co(II), Ni(II), Cu(II) and Cd(II) were obtained using a 1 : 1 mole ratio of the complex ligand and the metal salt. Heterotrinuclear complexes were obtained containing ReO(V) with UO 2 (VI) and Cu(II) using 2 : 1 mole ratios of the complex ligand and the metal salts. The complex ligands a and b coordinate with the heterometal ion via a nitrogen of the heterocyclic ring and the nitrogen atom of the C=N 7 group. All transition metal cations in the heteronuclear complexes have octahedral configurations, while UO 2 (VI) complexes have distorted dodecahedral geometry. The structures of the complexes were elucidated by IR, ESR, electronic and 1 H NMR spectra, magnetic moments, conductance and TG-DSC measurements. The antifungal activities of the complex ligands and their heteronuclear complexes towards Alternaria alternata and Aspergillus niger showed comparable behavior with some well-known antibiotics. [ABSTRACT FROM AUTHOR]

Herein, we describe the preparation of heteronuclear dirhodium-silver complexes by reaction between molecular Rh(II)-Rh(II) compounds [Rh2(μ-O2CR)4L2] (R = Me, Ph (1), CH2OEt (2); L = solvent molecules) with paddlewheel structure and PPh4[Ag(CN)2]. One-dimensional coordination polymers of (PPh4)n[Rh2(μ-O2CR)4Ag(CN)2]n (R = Me (3), Ph (4), CH2OEt (5)) formula have been obtained by replacement of the two labile molecules in the axial positions of the paddlewheel structures by a [Ag(CN)2]− bridging unit. The crystal structures of 3–5 display a similar arrangement, having anionic chains with a wavy structure and bulky (PPh4)+ cations placed between the chains. The presence of the (PPh4)+ cations hinders the existence of intermolecular Ag-Ag interactions although several C-H····π interactions have been observed. A similar reaction between [Rh2(μ-O2CCMe3)4(HO2CCMe3)2] and PPh4[Ag(CN)2] led to the molecular compound (PPh4)2{Rh2(μ-O2CCMe3)4[Ag(CN)2]2} (6) by replacement of the axial HO2CCMe3 ligands by two [Ag(CN)2]− units. The trimethylacetate ligand increases the solubility of the complex during the crystallization favouring the formation of discrete heteronuclear species. [ABSTRACT FROM AUTHOR]