Inorganic Chemistry Communications (v.63, #C)

Contents List (iii-ix).

Neutral fac-[Re(NNN)(CO)3] complexes with NNN tridentate ligands containing pyrrole or indole by Antonio Shegani; Charalampos Triantis; Christos Kiritsis; Catherine Raptopoulou; Vassilis Psycharis; Maria Pelecanou; Ioannis Pirmettis; Minas Papadopoulos (1-4).
New neutral fac-ReNNN(CO)3 complexes where NNN are the Schiff base tridentate ligands N-(1H-pyrrol-2-ylmethylene)-2-(pyridin-2-yl)ethanamine (complex 1) and N-(1H-indol-2-ylmethylene)-2-(pyridin-2-yl)ethanamine (complex 2) were synthesized and characterized by elemental analyses, infrared and 1H and 13C NMR spectroscopies. The molecular structure of complex 1 was confirmed by X-ray crystallographic analysis that revealed a distorted octahedral geometry around Re.Display Omitted
Keywords: Rhenium(I); Tricarbonyl; Pyrrole; Indole; X-ray structure;

The host and the apohost frameworks of Zn2(ndc)2(DMF)2  ∙(H2O)4 (1  ∙ DMF ∙ H2O) and Zn2(bdc)2(H2O)2  ∙(DMF)2 (2·H2O·DMF), (H2ndc = 2,6-naphthalene dicarboxylic acid, H2bdc = benzene-1,4-dicarboxylic acid and DMF = N,N-Dimethylformamide), were synthesized, characterized and subsequently used for preparing of ZnO nanoparticles. The morphology of initial precursors has direct influence on agglomeration tendency of resulting ZnO nanoparticles. Linkers and coordinated solvent molecules are the two effective factors on the formation of zinc oxide nanoparticles from these metal–organic frameworks.The host and the apohost frameworks of two nano-porous MOFs with similar linkers were used for preparation of ZnO nanoparticles. The influence of guest molecules, coordinated solvent molecules and linker ligands on their morphology and agglomeration process was studied.Display Omitted
Keywords: Metal–organic framework; Nanoparticles; ZnO; Agglomeration; Linker; Solvent molecules;

Luminescent lanthanide coordination polymers [H2NMe2]3[Ln(DPA)3] (Ln = Eu, Tb, Sm, Dy; [H2NMe2]+  = dimethyl amino cation; H2DPA = 2,6-dipicolinic acid) are synthesized, whose multi-color can be tuned and even white color luminescence can be integrated. Besides, the fluorescent sensing property of the [H2NMe2]3[Tb(DPA)3] system is checked, which shows selective fluorescent quenching effect for Fe3 +.Luminescent lanthanide coordination polymers [H2NMe2]3[Ln(DPA)3] are synthesized, whose multi-color can be tuned and even white color luminescence can be integrated. Besides, [H2NMe2]3[Tb(DPA)3] shows selective fluorescent quenching effect for Fe3 +.Display Omitted
Keywords: Lanthanide coordination polymers; Luminescence; Sensing;

Three rare Ln–Na heterometallic 3D polymers based on sulfate anion: Syntheses, structures, and luminescence properties by Bin Zhai; Zhongyi Li; Chi Zhang; Fuli Zhang; Xiangfei Zhang; Fuqiang Zhang; Guangxiu Cao; Suzhi Li; Xiaoyan Yang (16-19).
Three Ln–Na heterometallic 3D polymers based on sulfate anion, [LnNa(SO4)2(H2O)] (Ln = Gd (1); Tb (2); Dy (3)), were synthesized under hydrothermal conditions, which are the first examples of Ln–Na sulfates. These compounds crystallize in the trigonal P3 1 21 space group, and display a 6-connected sma topological structure with a Schäfli symbol of (410·65). The characteristic analyses reveal that compounds 13 display excellent thermal stability, and all exhibit antiferromagnetic interactions between the metal centers. The luminescent properties of 2 and 3 show the characteristic terbium and dysprosium luminescence. The strong luminescence in the green light (5D4  →  7F5) region for 2 and blue light (4F9/2  →  6H15/2) region for 3 indicate that they may be excellent candidates for green or blue fluorescent materials.Three 3D [LnNa(SO4)2(H2O)] (Ln = Gd (1); Tb (2); Dy (3)) polymers were reported as the first example of Ln–Na heterometallic sulfates. These compounds display excellent thermal stability. The strong luminescence in the green light (5D4  →  7F5) region for 2 and blue light (4F9/2  →  6H15/2) region for 3 indicates that they may be outstanding candidates for green or blue fluorescent materials.Display Omitted
Keywords: Ln–Na; Sulfate; 3D polymer; Luminescence;

Solvent-free synthesis of new metal sulfate–oxalates containing chain-like building blocks by Furong Guo; Kang Xiao; Meng Yang; Lindong Luan; Zhien Lin (20-23).
Four new metal sulfate–oxalates were synthesized under solvent-free conditions. These compounds have single-layered, double-layered, and three-dimensional structures containing metal oxalate chains as building blocks. Topological analyses reveal that they have hcb, mog, and kgd topologies, respectively. Possible build-up processes for the formation of the hybrid frameworks were proposed.Four open-framework metal sulfate–oxalates were synthesized under solvent-free conditions. These compounds display hcb, mog, and kgd topologies. Possible build-up processes for the formation of these hybrid frameworks were proposed.Display Omitted
Keywords: Solvent-free synthesis; Metal sulfate–oxalates; Inorganic–organic hybrid solids; Building blocks; Topology;

Two new 1-D and 2-D inorganic–organic hybrid polyoxomolybdates [H2dap]2[x-Mo8O26]·2H2O (1) and [Cu(dap)2]2[β-Mo8O26] (2) (dap = 1,2-propanediamine) have been hydrothermally synthesized and structurally characterized by elemental analyses, IR spectra, powder X-ray diffraction and single-crystal X-ray diffraction. The most remarkable structural differences between them are that 1 displays a 1-D chain constructed from [x-Mo8O26]4 − clusters through two terminal O atoms from adjacent [x-Mo8O26]4 − clusters whereas 2 demonstrates the 2-D extended layer made up of [β-Mo8O26]4 − clusters via [Cu(dap)2]2 + connectors. To our knowledge, the [x-Mo8O26]4 − cluster in 1 is reported for the first time. The thermogravimetric (TG) curve of 1 shows a two-step weight loss whereas the TG decomposition of 2 only proceeds in one stage. Additionally, their electrochemical behaviors and their photocatalytic degradation properties towards rhodamine-B are also investigated.Two 1-D and 2-D inorganic–organic hybrid polyoxomolybdates [H2dap]2[x-Mo8O26]·2H2O (1) and [Cu(dap)2]2[β-Mo8O26] (2) (dap = 1,2-propanediamine) have been hydrothermally synthesized and structurally characterized.Display Omitted
Keywords: Octamolybdate; Polyoxometalate; Electrochemistry; Photocatalytic degradation;

A novel Wells–Dawson polyoxometalate (POM)-based metal–organic framework (MOF) constructed from bi(triazole) ligand and azo anion, namely, [Ag13(L)6(N2)(HP2W18O62)] (1) (HL = 4-(1 H-1,2,4-triazol-3-yl)-2 H-1,2,4-triazolyl) has been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, IR spectra, PXRD analysis. In compound 1, the rigid bi(triazole) ligands connected AgI ions to construct a 2D metal–organic layer, which was further extended by azo anions forming a 3D framework. The Wells–Dawson type [P2W18O62]6 − anion as a multidentate inorganic ligand coordinated with the AgI ions, consolidating the 3D MOF. The L ligands and azo anions were in-situ transformed from a bi(triazole) derivative, which has never been observed in previous reports. In addition, the electrocatalytic and photocatalytic properties of compound 1 have been investigated.A novel 3D Wells–Dawson polyoxometalate (POM)-based metal–organic framework (MOF) constructed from the in-situ transformed bi(triazole) and azo ligands was obtained, which represents the first example of POM-based MOFs containing azo ligand.Display Omitted
Keywords: Wells–Dawson polyoxometalate; Metal–organic framework; In-situ ligand transformation; Bi(triazole) ligand; Azo anion;

A new simple receptor 1 based on the combination of julolidine and 2-(aminomethyl)benzenamine groups was prepared. It exhibited a ‘turn-on fluorescence type’ mode with high selectivity in the presence of Zn2 +. Noticeably, receptor 1 could clearly distinguish Zn2 + from Cd2 +. The mechanism of fluorescence enhancement of 1 for zinc was explained by theoretical calculations. Moreover, sensor 1 had a sufficiently low detection limit (10.9 μM), which is below than the WHO recommendation level (76 μM) for drinking water. Therefore, 1 can serve as a practical chemosensor for zinc ion in an aqueous solution.A new simple chemosensor 1 based on the combination of julolidine and 2-(aminomethyl)benzenamine groups was prepared for a ‘turn-on fluorescence type’ mode in the presence of Zn2 +. Noticeably, receptor 1 could clearly distinguish Zn2 + from Cd2 +. The mechanism of fluorescence enhancement of 1 for zinc was explained by theoretical calculations, and 1 had a sufficiently low detection limit (10.9 μM), which is below than the WHO recommendation level (76 μM) for drinking water.Display Omitted
Keywords: Zinc ion; Fluorescent chemosensor; Schiff base; CHEF effect; C=N isomerization; Theoretical calculations;

A new co-crystallized complex [Me2NH2]6[VIV 12VV 6O42][VON(CH2CH2O)3]·2H2O (1) based on mixed valence polyoxovanadate [VIV 12VV 6O42]6 − and a new mononuclear vanadium complex [VON(CH2CH2O)3] (2) were synthesized by controlling conditions of solvothermal synthesis and characterized by single crystal XRD, IR, XPS and EA, respectively. The compound 1 presents interesting antiferromagnetic interaction in solid state and luminescent property in aqueous solution.The co-crystallization compound based on polyoxovanadates and mononuclear vanadium complex was firstly prepared by solvo-thermal reaction. The magnetic measurements reveal the presence of antiferromagnetic interaction between VIV ions in the title compound and it emits interesting blue luminescence in aqueous solution.Display Omitted
Keywords: Polyoxovanadates; Mononuclear vanadium; Cluster; Co-crystallization; Luminescent property;

A one-dimensional (1-D) selenidostannate, [AEPPH2]2[Sn5Se12] (AEPP =  N-aminoethylpiperazine) (1), has been prepared under solvothermal condition and characterized. Single crystal X-ray analysis reveals that compound 1 crystallizes in the triclinic space group P-1, a  = 10.6351(7) Å, b  = 10.6850(7) Å, c  = 10.7771(7) Å, α  = 61.3440(10)°, β  = 62.4420(10)°, γ  = 67.4680(10). With distinct linkage modes between SnSe4 tetrahedrons and SnSe6 octahedrons, a secondary building unit (SBU) [Sn5Se14] is formed. Compound 1 contains infinite bead-like chains built up by the [Sn5Se14] SBUs, and the protonated [AEPPH2]2 + cations are located between the chain spaces. A pseudo 3-D network is formed through C–H···Se and N–H···Se hydrogen bonds between adjacent chains. Its optical property and theoretical band structure and density of state (DOS) calculations have also been studied.A one-dimensional (1-D) selenidostannate based on [Sn5Se14] SBUs was synthesized and structurally characterized.Display Omitted
Keywords: Chalcogenides; Selenidostannates; Infinite chain structure; Semiconductor material; Electronic calculation;

Mesoporous In2O3 materials were synthesized by calcining indium-organic frameworks (InOFs, CPM-5 and MIL-68), which were further successfully utilized to detect toxic HCHO vapor. By taking the intrinsic structural features of two InOF precursors into account, the surface areas of produced indium oxides were well investigated via controlling the calcination temperature. The influence of surface area on the gas sensing performance was studied in detail. Porous In2O3 prepared by heat treatment at 650 °C showed the highest responses to 50 ppm HCHO (Rg/Ra = 31.8 and 38.0, respectively; Rg, resistance in gas; Ra, resistance in air) at 210 °C, which surpass the values of all the reported In2O3 materials to date under the similar conditions. The promising HCHO-sensing properties enable these InOF-templated mesoporous In2O3 materials to be competitive candidates for detecting poisonous formaldehyde in practice.Mesoporous In2O3 materials successfully produced by calcining indium-organic frameworks showing tunable porosity and high responses to HCHO, which surpass the values of all the reported In2O3 materials under the similar conditions.Display Omitted
Keywords: Indium-organic frameworks; Mesoporous In2O3; Formaldehyde; Gas-sensor;

The rates of oxidation of 3,5-di-tert-butyl catechol (3,5-DTBC) to 3,5-di-tert-butylbenzoquinone (3,5-DTBQ) by atmospheric dioxygen in the presence of five nickel(II)-polyoximate complexes as catalysts were measured at five different substrate-to-catalyst ratios. In all cases, saturation kinetics were observed at high substrate concentration. Analysis of the data using the Michaelis Menten model reveals rate constant values (kcat) ranging from 120 to 400 h− 1, which are comparable to results for other Ni(II)-polyoximate complexes in the literature. For the set of five catalysts examined in this work, those with the fewer number of coordinating groups on their polyoximate ligands showed the highest rates of reaction, while those with the higher number of coordinating groups showed the lowest rates of reaction. These results suggest that greater flexibility and possibly lower hindrance in the coordination sphere of the nickel centers of the catalysts enhance the rate of catalysis.The rate of the transformation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butylbenzoquinone in the presence of nickel(II)-polyoximate catalysts is monitored by the growth of the quinone absorbance at 400 nm.Display Omitted
Keywords: Catechol; Quinone; Oxidation; Nickel; Oximate; Catalyst;

Synthesis and reactivity of cis-FeH2(dcpe)2 (dcpe = 1,2-bis(dicyclohexylphosphino)ethane) by Owen T. Summerscales; Brian L. Scott; Hari S. Viswanathan; Andrew D. Sutton (57-60).
A new six-coordinate iron dihydride cis-FeH2(dcpe)2 (1) has been synthesized (dcpe = 1,2-bis(dicyclohexylphosphino)ethane). It has been found to react with either 1,4-cyclohexadiene or tert-butylethylene in toluene to give the respected hydrogenated hydrocarbon and the zero valent species Fe(dcpe)(toluene) (2). When this reaction with acceptor olefins was performed in methylcyclohexane, transfer dehydrogenation was observed to give low-yields of iron-bound toluene in 2.
Keywords: Iron; Catalyst; C–H activation;

Density functional theory calculations (B3LYP and B2PLYP-D2) have been utilized to design and characterize novel homoatomic lithium(0) organometallic complexes of the NHC → Li–Li ← NHC type (NHC = N-heterocyclic carbenes). The computed Li–Li bond length and energy are consistent with those experimentally observed for Li2(g). These and other structural and energetic data suggest that such organolithium compounds should be viable targets for synthesis. These compounds would represent a new class of molecular “allotropes” and could have novel reactivities.Display Omitted
Keywords: Li(0) organometallic complex; NHC ligand; Homoatomic Li–Li bond; DFT computation;

Two novel 2-D organic–inorganic hybrid silicotungstates [H2en][Cu(en)2(H2O)]2{[Cu(en)2]3[Cu(en)(ox)]2[Ln2(ox)(α-SiW11O39)2]}·nH2O (Ln = ErIII, n = 10 for 1, Ln = SmIII, n = 8 for 2) with mixed organic ligands of ox and en (ox = oxalate, en = ethylenediamine) have been hydrothermally synthesized and characterized by IR spectrum, thermogravimetric analysis (TGA), power X-ray diffraction (PXRD) and X-ray single-crystal diffraction, respectively. Notably, 1 and 2 are isomorphic and exhibit the first novel 2D organic–inorganic hybrid silicotungstates assembled by {Cu2Ln2(ox)(SiW11)2} dimers and [Cu(en)(ox)]/[Cu(en)2] linkers. Furthermore, the TG curve of 1 and 2 display three steps of weight loss in the range of 25–1000 °C.A novel 2-D organic–inorganic hybrid polyoxotungstate with mixed organic ligands of oxalate (ox) and ethylenediamine (en) has been hydrothermally made, in which the adjacent dimeric cluster units, {[Cu(en)2]2[Er2(ox)(α-SiW11O39)2}3 −, are linked each other by double [Cu(en)(ox)] bridges and single [Cu(en)2]2 + bridges to generate a 2-D layer, showing the first organic–inorganic hybrid 2-D Cu–Ln heterometallic silicotungstates with mixed organic ligands of ox and en.Display Omitted
Keywords: Polyoxometalate; Hydrothermal synthesis; TM–Ln heterometallic hybrid; Oxalate-bridging;

A [Cu4I] cluster based metal-organic framework to detect F ions by He Chen; Ping-Xiao Liu; Shu-Ping Zhuo; Xing Meng; Zi-Yan Zhou; Hai-Ning Wang (69-73).
A new metal-organic framework, namely [Cu4I(TIPE)3].3I (1) (TIPE = tetra(3-imidazoylphenyl)ethylene), has been synthesized in the presence of sulfosalicylic acid under hydrothermal condition. Single-crystal X-ray diffraction shows that compound 1 exhibits a 2-nodal (4, 12)-connected interpenetrating network. Its luminescent property has been investigated at room temperature. Moreover, it has been used to detect halogen ions, and the experimental results show that it can selectively sense F ions through fluorescence quenching. The detection limit towards F ions is calculated to be 2.11 × 10− 6  mol/L.A framework [Cu4I(TIPE)3].3I based on Cu4I clusters has been synthesized by hydrothermal method. Luminescent properties of compound 1 have been investigated. It should be mentioned that this 3D cationic framework can be used as a luminescent probe to detect F ions in the aqueous solution. The detection limit of compound 1 towards F ions is calculated to be 2.11 × 10− 6  mol/L.Display Omitted
Keywords: Metal-organic frameworks; (4, 12)-Connected network; Fluorescent properties; Ion detection;

Anti-Mycobacterium tuberculosis activity of platinum(II)/N,N-disubstituted-N′-acyl thiourea complexes by Ana M. Plutín; Anislay Alvarez; Raúl Mocelo; Raúl Ramos; Eduardo E. Castellano; Monize M. da Silva; Legna Colina-Vegas; Fernando R. Pavan; Alzir A. Batista (74-80).
Synthesis, characterization and anti-Mycobacterium tuberculosis assays of new platinum(II)/dppf/N,N-disubstituted-N′-acyl thiourea complexes with general formulae [Pt(dppf)(L)]PF6, [dppf = 1,1′-bis(diphenylphosphino)ferrocene; L =  N,N-disubstituted-N′-acyl thioureas] is reported. The complexes were characterized by elemental analysis, molar conductivity, IR, NMR (1H, 13C and 31P{1H}) spectroscopy. The spectroscopic data are consistent with the complexes containing one dppf and one O, S chelated ligand. The crystal structures of complexes with N,N-diphenyl-N′-benzoylthiourea (L4), N,N-diethyl-N′-furoylthiourea (L5) and N,N-diphenyl-N′-(thiophene-2-carbonyl)thiourea (L8) were determined by X-ray crystallography, confirming the coordination of the ligands with the metal through sulfur and oxygen atoms, forming distorted square-planar structures. The complexes were screened with respect to their anti-M. tuberculosis activity (H37Rv ATCC 27294).The syntheses of the complexes with general formulae [Pt(dppf)(L)]PF6 (L =  N,N-disubstituted-N′-acyl thiourea and dppf = 1,1′-(diphenylphosphine)ferrocene; L =  N,N-disubstituted-N′-acyl thioureas] are reported. The complexes were characterized by elemental analysis, molar conductivity, IR, NMR (1H, 13C and 31P{1 H}) spectroscopy and X-ray spectroscopy. The complexes showed anti-Mycobacterium tuberculosis activity as good as the ethambutol, a first-line drug used in the tuberculosis treatment.Display Omitted
Keywords: Platinum(II) complexes; 1,1′-Bis(diphenylphosphino)ferrocene; N,N-Disubstituted-N′-acyl thioureas; Anti-Mycobacterium tuberculosis assays;

Crystal structure and characterization of a novel luminescent 1D coordination polymer: [Ca9(μ–H2O)9(picolinate)18]·4H2O by Remya M. Nair; M.R. Sudarsanakumar; S. Suma; M.R. Prathapachandra Kurup; P.K. Sudhadevi Antharjanam (81-85).
Single crystals of a novel 1D coordination polymer, [Ca9(μ–H2O)9(picolinate)18]·4H2O were grown by single gel diffusion technique. Sodium metasilicate was used for gel preparation. Single crystal X-ray diffraction studies reveal that the compound crystallizes in triclinic space group . The crystal possesses a large asymmetric unit with bridging picolinate ligands and water molecules. The 1D chain like structure constructs a 2D supramolecular architecture via the hydrogen bonding interactions. The grown crystals were further characterized by elemental analysis, powder X-ray diffraction study, FT-IR and UV–Visible spectral studies. The luminescent behaviour of the ligand and the complex was also investigated.Schematic representation of array of bridged Ca(II) atomsSingle crystals of a new 1D coordination polymer [Ca9(μ–H2O)9(picolinate)18]·4H2O have been grown by single gel diffusion technique. The compound crystallizes in triclinic space group P-1. The crystal possesses a large asymmetric unit with bridging picolinate ligands and water molecules. Single crystal X-ray diffraction study revealed the polymeric structure of the compound. The compound consists of three stranded 1D chains formed by metal atoms, oxygen atoms of carboxylate group and water molecules. The luminescent properties of the ligand and the complex were also studied.Display Omitted
Keywords: Crystal structure; Fluorescence; Coordination polymer; Supramolecular architecture; Gel diffusion method;

Multinuclear NMR and UV–Vis spectroscopy of site directed mutants of the diabetes drug target protein mitoNEET suggest that folding is intimately coupled to iron–sulfur cluster formation by S.K. Benson; K.M. Boyce; R.M. Bunker; N.B. Collins; K.J. Daily; A.S. Esway; G.T. Gilmore; C.W. Hartzler; G.P. Howard; N.A. Kasmar; K.J. Kennedy; B.L. King; T.N. Kordahi; T.A. Mattioli; D.M. Pugh; L.A. Ray; S.L. Ross; M.H. Torcasio; D.P. Webber; D.L. Morris; T.C. Leeper (86-92).
Further understanding of the mitochondrial protein mitoNEET could lead to advancements in drug design for the treatment of mitochondrial diseases. Previous studies have shown that mitoNEET's iron–sulfur cluster plays a key role in its biochemistry. In order to gain insight into the structural stability and folding of mitoNEET's iron–sulfur clusters, mutants were created using site-directed mutagenesis. NMR and UV–Vis spectroscopic analysis of these mutants suggested that half had successfully hindered protein folding that in turn, increased lability and eventually loss of functional iron–sulfur clusters. Understanding the significance of this coupling of lability to misfolding could be key to learning mitoNEET‘s mode of action in mitochondria. These findings may allow mitoNEET to be utilized for therapeutics and a better understanding of mitochondrial-based diseases.Using site-directed mutagenesis nineteen undergraduate students investigated the inorganic biochemistry of the CDGSH-type iron sulfur cluster protein and diabetes drug target mitoNEET. NMR and UV–Vis spectroscopy of these mutants confirm the notion that cluster ligation is intimately tied to domain folding.Display Omitted
Keywords: MitoNEET; Iron-sulfur cluster; NMR; UV-Vis; Undergraduate research;

A new luminescent silver-based probe for on/off sulfide determination by Daniel Fonseca Segura; João Flávio da Silveira Petruci; Arnaldo Alves Cardoso; Regina Célia Galvão Frem; Adelino Vieirade de Godoy Netto; Neil R. Champness (93-95).
The sulfide anion is a corrosive, toxic and harmful compound found in a wide range of anoxic environments. Metal-based complexes have been used as luminescent probes for sulfide determination. However, their synthesis usually involves laborious procedures and the use of toxic reagents. In this paper, we describe the synthesis, characterization and application of a new, sensitive and selective silver complex probe for sulfide detection. The process of sulfide determination is based on rapid reaction in aqueous/methanolic media between the silver (I) complex and sulfide leading to an increase in fluorescence intensity. Analytical performance has been studied in the concentration range of 190 to 950 nmol L− 1 of sulfide with suitable linearity, and the limit of detection was calculated to be (3σ/S) to 20 nmol L− 1. The probe's selectivity to S2 − was evaluated over other competing anions showing excellent results and its reversibility was demonstrated upon addition of AgCF3SO3.We describe the synthesis, characterization and application of a new, sensitive and selective silver complex probe for sulfide detection. The process of sulfide determination is based on rapid reaction in aqueous/methanolic media between the silver (I) complex and sulfide leading to an increase in fluorescence intensity.Display Omitted
Keywords: Luminescent probes; Silver complex; Sulfide detection;

A new homoleptic coordination compound of ruthenium and norfloxacin and its interaction with human serum albumin by Felipe Costa Claro Reis; Joana Stefani Viana Coelho; Wallance Moreira Pazin; Sofia Nikolaou (96-100).
This work presents a new coordination compound of ruthenium and the norfloxacin antibiotics, as well as its interaction with human serum albumin (HSA). The ESI HRMS spectrum of [Ru(nor)3] (nor = norfloxacinate, C16H17FN3O3 ) displayed the protonated molecular ion at m/z 1057.3, while the HRMS/MS spectra displayed peaks at m/z 958.4 and 639.3 assigned to the gaseous phase norfloxacin adducts (Hnor)3·H+ and (Hnor)2·H+. Coordination to Ru(III) remarkably enhances the water solubility of norfloxacin. The complex absorption spectrum in aqueous medium is dominated by the norfloxacin transitions in the UV region but also displays a broad shoulder around 370 nm, which possibly overlaps with ligand-field transitions. Stern–Volmer analysis of human serum albumin (HSA) fluorescence quenching by [Ru(nor)3] showed that both dynamic and static mechanisms contribute to the quenching. Lifetime measurements demonstrated that the predominance of one pathway over the other depends on temperature variations. Finally, the analysis of thermodynamic parameters leads to the conclusions that the interaction of the novel complex with HSA is spontaneous and that this interaction occurs through the formation of hydrogen bonds and van der Waals forces (ΔH = − 259.2 kJ/mol and ΔS = − 779.9 kJ/mol·K).The homoleptic complex [Ru(nor)3] has been synthesized, and the coordination to ruthenium remarkably influences the solubility of norfloxacin, being the [Ru(nor)3] complex fully water soluble. The compound can be properly stored/transported in the body by human serum albumin, since coordinated norfloxacin interacts with HSA through hydrogen bonds and van der Waal interactions.Display Omitted
Keywords: Ruthenium; Norfloxacin; Human serum albumin; Life time measurements;

Reactions of CuCl2, K2[Ni(CN)4]/K3[Co(CN)6], and 5-amino-1H-tetrazole led to cyanide-bridged mixed-valence Cu(II/I) complexes, [Cu(H2O)3Cu3(CN)5] (1) and [Cu(H2O)4][Cu4(CN)6] (2).The uncommon semi-closed {Cu2(CN)3} dimmers in 1 are bridged by μ 3-C,C,N cyanide ligands to afford rare 1D centipedal-like chain motifs, which are further bridged by μ 2-C,N and metalloligand “CN–Cu(4)–CN” to finish sophisticated zeolite-like 3-D structure. Topologically, 1 is the first example of uninodal 7-connected sev-like cyanide-bridged network. Compound 2 consists of two-dimensional honeycomb-related anionic layers [Cu4(CN)6]2 −, within which the [Cu(H2O)4]2 + cations are intercalated into alternate interlamellar space. Compound 1 shows antiferromagnetic couple arising from pure ground-state configuration of Cu(II) mediated by diamagnetic bridges –CN–CuI–CN −. The inclusion compound 2 shows blue photoluminescence originated from Cu(I) center to the unoccupied π* orbital of the cyanide ligand (MLCT) charge transfer.Cyanide-bridged mixed-valence Cu(II/I) complexes [Cu(H2O)3Cu3(CN)5] (1) and [Cu(H2O)4][Cu4(CN)6] (2) have been synthesized and characterized. Compound 1 is the first example of uninodal 7-connected sev-like open framework, constructed by uncommon semi-closed trinuclear subunits and bridging cyanide ligands, and representing weak antiferromagnetic coupling of the CuII ions mediated by the –NC–CuI–CN– diamagnetic bridges. For compound 2, unique cationic guests [Cu(H2O)4]2 + are encapsulated in the anionic host framework [Cu4(CN)6]2 −, which shows photoluminescence property induced from MLCT.Display Omitted
Keywords: Cyanide-bridged; Mixed-valence CuI/CuIIcomplexes; Topology characterization; Luminescent property; Magnetic property;

Novel hexanuclear and octanuclear zinc alkyl cages derived from a bis-oxamidate ligand by Ernesto Rufino-Felipe; Judith Caballero-Jiménez; Luis-Guillermo Guerrero-Ramírez; Marcos Flores-Álamo; Miguel-Ángel Muñoz-Hernández (107-110).
1 and 2 were prepared by coordination self-assembly from reacting N,N′-bis(3,5-di-tert-buthyl-2-phenol)oxamide (L-H4) with ZnEt2 in toluene and THF, respectively. The molecular X-ray structures show 1 as an octanuclear Zn8 cage and 2 as a hexanuclear Zn6 cage. The nuclearity of these cages is driven by the solvent, in fact 1 gives 2 upon addition of THF. Good polymer conversions for the ROP of rac-lactide were achieved by using 1 and 2 with alcohols as co-catalysts.
Keywords: Zn cages; Coordination self-assembly; Nuclearity control; Zn catalysts; ROP rac-lactide;