Inorganic Chemistry Communications (v.11, #11)

Contents List (iii-x).

A new complex based on chelate copper coordination with divacant polyanion ligand [γ-PW10O36]7− by Xizheng Liu; Xiaocui Wei; Lin Xu; Guanggang Gao; Fengyan Li (1313-1315).
A new complex based on decatungstophosphate and chelated copper atoms, [Hen][Cu(en)2(H2O)]2  · {[Cu(en)2(H2O)] · [γ-PW10O36]} · 9H2O (1) (en = ethylenediamine) was structurally characterized by single crystal X-ray diffraction, and the polyoxoanions [γ-PW10O36]7− was connected with chelate copper complex.A new complex based on decatungstophosphate and chelated copper atoms, [Hen][Cu(en)2(H2O)]2 · {[Cu(en)2(H2O)] · [γ-PW10O36]} · 9H2O (1) (en = ethylenediamine) has been synthesized by conventional methods and characterized by single crystal X-ray diffraction, IR spectra and electronic spectra. The structure analysis of 1 indicates that the complex contains a divacant polyanion [γ-PW10O36]7− connected with a chelated copper atom. Magnetic susceptibility measurement for 1 in the temperature range 2–300 K reveals the occurrence of intermolecular antiferromagnetic interactions between chelate copper (II) complexes at lower temperature.
Keywords: Divacant polyoxometalate; Crystal structure; Chelate copper; Magnetism;

In the crystal state of three solvent-induced pseudo-polymorphic bimetallic Zn–Nd complexes [ZnNdL(OAc)(NO3)2(DMF)] · solvate (solvate: MeCN (1), THF (2), EtOH (3); H2L  =  N,N′-bis(3-methoxy-salicylidene)phenylene-1,2-diamine), the solid NIR luminescent change was strongly related to the packing structure caused by the intermolecular π–π interactions.Three solvent-induced pseudo-polymorphic bimetallic Zn–Nd complexes [ZnNdL(OAc)(NO3)2(DMF)] · solvate (solvate: MeCN (1), THF (2), EtOH (3); H2L  =  N,N′-bis(3-methoxy-salicylidene)phenylene-1,2-diamine) were obtained, and their solid NIR luminescence related to the packing structure from the intermolecular π–π interactions was discussed.
Keywords: Solvent-induced pseudo-polymorphism; Bimetallic Zn–Nd Schiff-base complex; Intermolecular π–π interaction; NIR luminescence;

Two trimeric tri-TiIV-substituted Keggin tungstogermanates based on tetrahedral linkers by Yuan-Hang Ren; Shu-Xia Liu; Rui-Ge Cao; Xin-Yu Zhao; Jian-Fang Cao; Chao-Ying Gao (1320-1322).
Reactions of [ γ - GeW 10 O 36 ] 8 - and TiO(SO4) in open air conditions obtained two trimeric nine-titanium contained tungstogermanate under different pH. The two compounds are constructed by three tri-TiIV-substituted A-α-[Ti3GeW9O38] fragments through tetrahedral GeO4/SO4 tetrahedral linker. The structures contain nine-titanium cavities connected through Ti–O–Ti and Ti–O–Ge/Ti–O–S bridges which wrap K+ in them.Two trimeric nine-TiIV contained tungstogermanates K14{K ⊂ [(Ge(OH)O3)(GeW9Ti3O38H2)3]} · 42H2O 1 and K10{K ⊂ [(SO4)(GeW9Ti3O38H3)3] · 40H2O 2 have been conventionally synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. They were constructed from three tri-substituted A-α-[GeW9Ti3O38] and GeO4/SO4 tetrahedral linker. They display the first example of trimeric titanium-substituted tungstogermanates, which contain both Ti–O–Ti and Ti–O–Ge/Ti–O–S bridges.
Keywords: Tungstogermanate; Titanium; Conventional synthesis; Keggin;

Dimeric gadolinium complexes containing polyaminopolycarboxylate bisamide ligands have been synthesized and characterized. They contain one coordinated water molecule in the solid state and in aqueous medium. Their thermodynamic stability is found to be high and suitable for MRI investigation.Dimeric gadolinium complexes containing polyaminopolycarboxylate bisamide ligands have been synthesized and characterized. They contain one coordinated water molecule in the solid state and in aqueous medium. Their thermodynamic stability is found to be high and suitable for MRI investigation.
Keywords: Gadolinium; Macrocyclic ligand; Crystal structure; Thermodynamic stability;

The first polymeric thiogallate with lanthanide-containing counter cation, [Dy2(en)62-OH)2]Ga4S8 by Chun-Ying Li; Jian Zhou; Guo-Qing Bian; Ming-Hui Zhang; Jie Dai (1327-1329).
Although some thiogallates with transition metal complex cation have been reported, the title compound, containing 1D infinite sinusoidal [ GaS 2 ] - anions and hydroxy bridged dinuclear dysprosium complex cations, is the only example of the thiogallates with lanthanide-containing counter cation.The title compound, [Dy2(en)62-OH)2]Ga4S8 (en = ethylenediamine), contains 1D infinite sinusoidal [ GaS 2 - ] n anions and hydroxy bridged dinuclear dysprosium complex cations. Two bridging hydroxy ions connect two inversion-related Dy3+ ions to form a centrosymmetric dimer, in which a Dy2O2 rhomboidal core is formed. The title compound is the only example of the thiogallates with lanthanide-containing counter cation.
Keywords: Thiogallate; Lanthanide complex; Solvothermal synthesis; Crystal structure;

Two fluorescent [Ag4(sac)4(mpyz)2(H2O)2] and [Ag2(sac)2(pyzca)2] complexes (sac = saccharinate, mpyz = 2-methylpyrazine and pyzca = pyrazine-2-carboxamide) have been synthesized and characterized. Sac ligands bridge the silver(I) centers resulting in Ag–Ag contacts.Two new silver(I)–saccharinato (sac) complexes [Ag4(sac)4(mpyz)2(H2O)2] (1), and [Ag2(sac)2(pyzca)2] (2), (mpyz = 2-methylpyrazine, pyzca = pyrazine-2-carboxamide) have been synthesized and structurally characterized. Bridging of silver(I) centers by sac ligands results in argentophilic contacts of 3.192(1) Å for 1, and 3.168(2) Å for 2. These Ag⋯Ag interactions were discussed in terms of bond distances and angles around the silver(I) ion. Both complexes exhibit strong blue luminescence at room temperature in the solid state.
Keywords: Silver(I) complexes; Saccharinate; 2-Methylpyrazine; Pyrazine-2-carboxamide; Crystal structure; Fluorescence;

Interconversion between cyclotrimer and chain of pd(II) complex by Tae Hwan Noh; Sung Jin Moon; Young Mee Na; Byung Jo Ha; Ok-Sang Jung (1334-1336).
Reversible interconversion between cyclotrimer and chain of [Pd(Me4en)(nic)]3(PF6)3 (Me4en =  N,N,N′,N′-tetramethylethylenediamine, nic = nicotinate) was observed in coordinating solvents.Interconversion between cyclotrimer and chain of [Pd(Me4en)(nic)]3(PF6)3 (Me4en =  N,N,N′,N′-tetramethylethylenediamine, nic = nicotinate) via a reversible ring-opening process in solution was carried out. The unusual interconversion can be explained via the ring-strains of the cyclotrimer and the coordinating ability of solvents.
Keywords: Cyclotrimer; Nicotinate; Palladium(II) complex; Ring-opening; Solvent effects;

A heterometallic trinuclear complex with monovalent platinum consisting of a [Pt2Hg] cluster bridged by two μ3-Cl atoms and another tetranuclear complex with monovalent palladium owning the structural core of open cubane-like [Hg2Pd2Cl2I2] framework was synthesized by self-assembly reactions.A heterometallic trinuclear complex with monovalent platinum consisting of a [Pt2Hg] cluster bridged by two μ3-Cl atoms and another tetranuclear complex with monovalent palladium owning the structural core of open cubane-like [Hg2Pd2Cl2I2] framework were synthesized by self-assembly reactions.
Keywords: Crystal structures; Palladium(I); Platinum(I); Heterometallic complexes; Photoluminescence;

Synthesis, characterization, DNA-binding properties and electronic structure (DFT) of ruthenium oligopyridine complexes by Konstantinos Christopoulos; Konstantina Karidi; Athanassios Tsipis; Achilleas Garoufis (1341-1346).
The complexes of the general formulae [Ru(terpy)(dcbpy)X] n (dcbpy = 4,4′-dicarboxy-2,2′-bipyridine; X = Cl, n  = +1; X = NO, n  = +3; X = NO2, n  = −1) have been synthesized and characterized. The DNA affinity of the nitrite complex together with other structurally similar complexes was calculated. DFT and TD-DFT electronic structure calculations have been used to describe the structural and spectroscopic properties of complexes.The complexes of the general formulae [Ru(terpy)(dcbpy)X] q (dcbpy = 4,4′-dicarboxy-2,2′-bipyridine; X = Cl, 1; NO+, 2; NO 2 - , 3; q  = 1+, 3+ and 1−, respectively) have been synthesized and characterized. The DNA binding properties of structurally similar complexes [Ru(terpy)(dcbpy)NO2], 3, [Ru(terpy)(4-CO2-4′-Mebpy)NO2], 4, and [Ru(terpy)(bpy)NO2]+, 5, were studied, and their DNA affinities (K b) were calculated as 6 ± 0.3 × 104  M−1, 8 ± 1.1 × 104  M−1 and 9.7 ± 0.02 × 106  M−1. The structural and spectroscopic properties of complexes 35 were investigated by DFT and TD DFT electronic structure calculations. The equilibrium geometries of complexes 35 in vacuum correspond to a distorted octahedral stereochemistry. The high-lying peaks of the absorption spectra of the complexes, ranging from 440 to 529 nm, are assigned to MLCT/LLCT transitions. These transitions are red-shifted upon adding carboxy substituents to the bipyridine ligand while the low-lying LLCT transitions, absorbing at 779 and 659 nm, are blue-shifted. Noteworthy is the excellent agreement of the TD DFT simulated absorption spectra in aqueous solution with the experimental ones.
Keywords: Ruthenium oligopyridine complexes; Absorption spectra; DNA binding; TD-DFT calculations;

Construction of three-dimensional Ln–Ag (Ln = Eu; Tm) coordination polymers based on isonicotinate and oxalate ligands by Ji-Xia Mou; Rong-Hua Zeng; Yong-Cai Qiu; Wei-Guang Zhang; Hong Deng; Matthias Zeller (1347-1351).
Two new 3D 4d–4f coordination polymer [Ln2Ag4(IN)5(ox)2(NO3)(H2O)2  · 3H2O] [Ln = Eu (1), Tm (2); IN = isonicotinate and ox = oxalate] had been synthesized and characterized. Both structures display same 3D heterometallic coordination frameworks based on rare zigzag lanthanide–oxalate–silver chains, Ag2(IN)3 units and IN linkers. The structures provide new opportunities for other 4d–4f heterometallic coordination frameworks containing isonicotinate ligand to be applied in the field of material science.Hexanuclear 4d–4f heterometallic coordination polymers, [Ln2Ag4(IN)5(ox)2(NO3)(H2O)2  · 3H2O] [Ln = Eu (1), Tm (2); IN = isonicotinate and ox = oxalate], have been synthesized by hydrothermal reaction of mixed organic ligands and metal salts. Both structures display the same unusual 3D heterometallic coordination frameworks based on rare zigzag lanthanide–oxalate–silver chains, Ag2(IN)3 units and IN linkers. The photoluminescent properties of complex 2 were studied.
Keywords: Isonicotinic acid; Ln(III)–Ag(I) heterometallic complexes; Lanthanide–oxalate–silver chains; Luminescence;

The first example of linkage isomerism for pyrazole ligands in platinum complexes by Anatoly V. Khripun; Nadezhda A. Bokach; Stanislav I. Selivanov; Matti Haukka; Mikhail D. Revenco; Vadim Yu. Kukushkin (1352-1355).
In the platinum(II) complex [ Pt ( Me-Pz ) 4 ] 2 + , 3(5)-methylpyrazole exhibits the linkage isomerism both in a solution and in the solid state.The cationic complex [Pt(Me-Pz)4](Cl)2 (12+ ·(Cl)2 ) has been prepared by the reaction of [PtCl2(Me-Pz)2] with an excess of 3(5)-methylpyrazole (3(5)-Me-Pz) and it was characterized by elemental analyses (C, H, N), ESI+-MS, IR, 1H and 13C NMR spectroscopies. Linkage isomerism of the coordinated pyrazole was observed in a solution for 12+ ·(Cl)2 with an overall 3:4 ratio for 3-Me-Pz and 5-Me-Pz metal-bound species, respectively. X-ray diffraction studies of two complexes, 12+ ·[PtCl4] and 12+ ·(pic)2 , allows the observation of different coordination modes of the 3(5)-Me-Pz ligand in the solid state, i.e. three coordinated 5-Me-Pz and one 3-Me-Pz in 12+ ·[PtCl4] and three coordinated 3-Me-Pz and one 5-Me-Pz in 12+ ·(pic)2 .
Keywords: Pyrazole complexes; Linkage isomerism; Platinum; Pyrazole tautomerism;

A four-spin ring with alternating magnetic interactions formed by pyridine-substituted nitronyl nitroxide radicals and Gd(III) ions: Crystal structure and magnetic properties by Jin-Xia Xu; Yue Ma; Gong-Feng Xu; Chao Wang; Dai-Zheng Liao; Zong-Hui Jiang; Shi-Ping Yan; Li-Cun Li (1356-1358).
In this paper, we present the synthesis, structure and magnetic property of a novel Gd(III) complex [Gd(hfac)3(NIT-5-Br-3py)]2, in which a NIT-5-Br-3py molecular acts as a bridging ligand linking two Gd(III) ions through the oxygen atom of the N–O group and nitrogen atom from the pyridine ring to form a four-spin system. It is worth noting that there are two different magnetic interactions between Gd(III) ion and NIT-5-Br-3py in one complex: a weak ferromagnetic interaction through the N–O group, and a much weaker antiferromagnetic interaction through pyridine ring.A novel complex, [Gd(hfac)3(NIT-5-Br-3py)]2 (hfac = hexafluoroacetylacetonat, NIT-5-Br-3py = 2-(4,4,5,5-tetramethyl-3-oxylimidazoline-1-oxide)-5-bromo-3-pyridine) has been synthesized and characterized structurally and magnetically, in which a NIT-5-Br-3py molecular acts as a bridge ligand linking two Gd(III) ions through the oxygen atom of the N–O group and nitrogen atom from the pyridine ring to form a four-spin system. The fitting result of the magnetic susceptibility shows two different magnetic interactions between Gd(III) ion and NIT-5-Br-3py in one complex: a weak ferromagnetic interaction (J 1  = +2.60 cm−1) through the N–O group, and a much weaker antiferromagnetic (J 2  = −0.24 cm−1) interaction through pyridine ring.
Keywords: Gadolinium(III) complex; Nitronyl nitroxide radical; Crystal structure; Magnetic interaction;

Ribose-protected thioguanosine (TG) exhibits remarkable preference for cesium over other alkali metal (Na+, K+, Rb+) and alkaline earth metal ions (Mg2+, Ca2+, Sr2+, Ba2+) in acetonitrile by 1H NMR measurements. The most distinct feature is that only in a cesium environment, the thioamide NH peak becomes highly broadened and finally disappeared, and the amino NH2 peak shows a downfield shift, suggesting that TG-based 1H NMR spectroscopic probe is factually useful for the detection of cesium from solid cesium-containing sources in organic solvents.Ribose-protected thioguanosine (TG) exhibited remarkable preference for cesium over other alkali metal (Na+, K+, Rb+) and alkaline earth metal ions (Mg2+, Ca2+, Sr2+, Ba2+) in acetonitrile by 1H NMR measurements. Furthermore, TG displayed excellent sensitivity for cesium even under 500/1 NaCl/CsCl and KCl/CsCl environments. The most distinct feature is that only in a cesium environment, the thioamide NH peak becomes highly broadened and finally disappeared, and the amino NH2 peak shows a downfield shift, suggesting that TG-based 1H NMR spectroscopic probe is factually useful for the detection of cesium from solid cesium-containing sources in organic solvents.
Keywords: Cesium; Selectivity; Sensitivity; Ribose-protected thioguanosine; NMR probe;

A novel (μ-OAc)2 bridged unsymmetric coordinated binuclear Mn(II) macrocyclic complex with ligating pendant-arm by Zhi-Quan Pan; Wen-Hao Ni; Hong Zhou; Xue-Lei Hu; Qi-Mao Huang; Juan Kong (1363-1366).
The Mn(II) dinuclear complex with an uncoordinating cavity was obtained by (2+2) condensition reaction between dialdehyde and branched polymine. The complex shows weakly antiferromagnetical coupling between two Mn(II) ions and the CAT-like activity.A novel binuclear manganese Mn(II) macrocyclic complex with two pyridylmethyl pendant arms, [Mn2 II(H2L)(μ-OAc)2](ClO4)2  · H2O, has been synthesized and characterized crystallographically and magnetically. The crystal structure of the complex shows that two manganese ions locate in the same head of the macrocycle, leaving an uncoordinating cavity to catch protons through oxide of phenolate and the nearby imine groups in another head. The electrochemical study demonstrates that the complex gives two couples of redox peaks with E 1/2 of 0.3775 V and 0.8409 V, respectively. The variable temperature magnetic susceptibility measurement on the sample displays weak antiferromagnetic interaction between two manganese (II) with the J  = −3.733(7) cm−1. This complex exhibits a moderate activity for catalyzing disproportionation of H2O2 to O2.
Keywords: Binuclear Mn(II)complex; Crystal structure; Magnetic property; Electrochemistry; Catalytic oxidation;

Two new polyoxometalates-based hybrids firstly synthesized in the ionic liquids by Na Zou; Weilin Chen; Yangguang Li; Wenli Liu; Enbo Wang (1367-1370).
Two new compounds (C6H11N2)4(W10O32) 1 and (C6H11N2)4(W6O19)(BF4)2 2 have been synthesized in the ionic liquids (ILs). To our best knowledge, it is the first time that polyoxometalates are synthesized in the ILs.Two new compounds (C6H11N2)4(W10O32) 1 and (C6H11N2)4(W6O19)(BF4)2 2 have been synthesized in the ionic liquids (ILs) and characterized by elemental analyses, IR, TG analyses, cyclic voltammetry and single-crystal X-ray diffraction. To our best knowledge, it is the first time that polyoxometalates are synthesized in the ILs.
Keywords: Polyoxometalates; Ionic liquids; Atmospheric pressure; Conventional synthesis;

This work presents two layered CuII coordination polymers with a flexible pyridinecarboxamide building block, and their significant structural discrepancy of the open and close 2-D networks results from the conformational isomerism of the ligands.Reaction of a flexible pyridinecarboxamide ligand N,N′-[(2,3,5,6-tetrafluoro-1,4-phenylene) bis(methylene)]bis(pyridine-4-carboxamide) (H2tfpbbp) with CuII chloride or perchlorate affords two coordination polymers {[Cu(H2tfpbbp)(tfpbbp)(H2O)] · 2DMF · 4H2O} n (1) and {[Cu(H2tfpbbp)2(ClO4)2] · 3H2O} n (2). Both complexes have 2-D (4,4) layered networks extended by the exo-bidentate bridging ligands, which however consist of distinct [Cu–ligand]4 meshes owing to the conformational difference of ligands. Their spectroscopic, thermal, and fluorescence properties have also been investigated.
Keywords: Flexible tecton; Ligand conformation; Coordination polymer; Crystal structure; Photoluminescence;

Nanobelts, nanosheets, and microcrystals of a supramolecular metal–organic framework (MOF), [Zn(BDC)(H2O)] n (1, BDC = 1,4-benzenedicarboxylate), was synthesized using ultrasonic method at ambient temperature. Sensing of ethylamine was conducted using nanosheets of 1 due to highly sensitive response of fluorescence emission of nanosheets of 1 to ethylamine.A supramolecular metal–organic framework (MOF) constructed by two-dimensional (2D) infinite coordination polymers, [Zn(BDC)(H2O)] n (1, BDC = 1,4-benzenedicarboxylate), was synthesized by the reaction of zinc acetate with H2BDC in dimethylformamide (DMF) under ultrasonic irradiation at ambient temperature and atmospheric pressure. Yield of 1 varied from 43.4% to 53.2% for the reaction time of 10–90 min. Samples with different morphologies, i.e. nanobelts, nanosheets, and microcrystals, were obtained under ultrasound irradiation for different reaction times. Fluorescence emission of nanosheets of [Zn(BDC)(H2O)] n was found to be highly sensitive to ethylamine, and solid state fluorescence intensity decreased with increasing contents of ethylamine in acetonitrile solution due to weak fluorescence quenching effect.
Keywords: Metal–organic framework; Nanomaterials; Ultrasonic synthesis; Fluorescence; Sensor;

Synthesis, structure and properties of two new 3D frameworks with primitive cubic topology by Xiang He; Chuan-De Wu; Ming-Xing Li; Stuart R. Batten (1378-1381).
Two new three-dimensional (3D) coordination polymer [Cu2(tetrazolate)3(OH)] n (1) and [Cd2(tetrazolate)3Br] n (2) were synthesized and structurally characterized. By the topology analysis, the complicated architecture of 1 and 2 are all simplified to be the 6-connected pcu-type net.Two new three-dimensional (3D) coordination polymer [Cu2(tetrazolate)3(OH)] n (1) and [Cd2(tetrazolate)3Br] n (2) were synthesized and structurally characterized. By the topology analysis, the complicated architecture of 1 and 2 are all simplified to be the 6-connected pcu-type net. The variable-temperature magnetic susceptibilities (5–300 K) of 1 shows antiferromagnetic interactions of copper(II) ions bridged tetrazolate ligands and/or hydroxide anion.
Keywords: Coordination polymers; Tetrazolate ligand; Topology; Magnetic property;

Synthesis, crystal structure and DNA-binding studies of a Ru(II) complex containing two main ligands by Jing Sun; Shuo Wu; Yan Han; Jie Liu; Liang-Nian Ji; Zong-Wan Mao (1382-1384).
A new Ru(II)-polypyridyl complex with two main ligands has been synthesized and structurally characterized. The complex exhibits a high binding affinity with calf thymus DNA. And plasmid pBR322 DNA can be cleaved by this complex under irradiation at 365 nm.A new Ru(II)-polypyridyl complex, [Ru(L)(dppz)2](PF6)4 (L = 5,5′-di(1-(trimethylammonio)methyl)-2,2′-dipyridyl cation; dppz = dipyrido[3,2-a:2′,3′-c]phenazine]), has been synthesized and structurally characterized. The binding of this complex with calf thymus DNA (CT-DNA) has been investigated by spectroscopic and viscosity measurement. Results indicate that the complex binds to CT-DNA via an intercalative mode. Moreover, the complex reveals a highly efficient DNA cleavage activity upon irradiation at 365 nm, during which supercoiled pBR322 DNA was converted to nicked DNA.
Keywords: Ru(II) complex; Polypyridyl ligands; DNA-binding; Photocleavage;

Monometallic and bimetallic europium(III) and terbium(III) complexes: Synthesis and luminescent properties by Gregory Richards; Jennifer Osterwyk; Jon Flikkema; Katherine Cobb; Matthew Sullivan; Shawn Swavey (1385-1387).
High yield and high purity lanthanide complexes by facile synthetic methods is presented. Luminescent properties in methanol solutions are presented.Eight new lanthanide complexes of the form Ln(L)3bipy and [Ln(L)3]2bpm were synthesized (where L = 2,2,6,6-tetramethyl-3,5-heptanedione (tmh) and 1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedione (tdh), bipy = 2,2′-bipyridine, bpm = 2,2′-bipyrimidine and Ln = Tb(III) or Eu(III)). The luminescent spectra are typical of Tb(III) and Eu(III) complexes with intense transitions at 545 nm for Tb(III) and 612 nm for the Eu(III) complexes. Energy gaps between the tmh ∗ orbitals and the 0DJ manifold of Eu(III) are too large to give efficient energy transfer therefore emission spectra for Eu(tmh)3bipy and [Eu(tmh)3]2bpm were not detected. Lifetimes are greatest for the Tb(III) complexes containing tmh terminal ligands while the longest lifetimes for the Eu(III) complexes occur with the tdh terminal ligands.
Keywords: Europium; Terbium; Bridged complexes; Luminescence; β-Diketones;

The new terpyridyl ligand 4′-phenyl-3,2′:6′,3′′-terpyridine (L) reacts with Zn(acac)2 to produce the binuclear complex [Zn2(μ-L)(acac)4] · H2O (acac = acetylacetonato). A mixture of intermolecular hydrogen bonds of the O–H/O, C–H/O and C–H/π type give raise to a 3D supramolecular framework.The new terpyridyl ligand 4′-phenyl-3,2′:6′,3′′-terpyridine (L) reacts with Zn(acac)2 to produce the dizinc complex [Zn2(μ-L)(acac)4] · H2O (1) (acac = acetylacetonato). The analysis of the crystal structure of this zero-dimensional (0D) complex shows the existence of two Zn(acac)2 centers bridged symmetrically by one μ-L ligand. The key role played by the acac and L ligands and the guest water molecule allows the generation of a series of intermolecular hydrogen bonds of the O–H/O, C–H/O and C–H/π type which give raise to a 3D supramolecular array. The observed C–H/π interactions are so widespread that all the π-rings present in the structure, viz., those belonging to the L ligand as well as the acetylacetonato chelate rings, participate as hydrogen bond acceptors.
Keywords: Polypyridine complexes; Supramolecular structure; C–H/π interaction; C–H/O interaction; Hydrogen bond;

Mononuclear copper(II) complex of benzimidazole-based ligand shows lower DNA binding ability but higher DNA cleavage activity as compared with its trinuclear analogue.Two copper(II) complexes, [CuLCl2] (1) and [Cu3 L′Cl6] (2) (L  = bis(2-benzimidazolylmethyl)amine, L′ = 2,4,6-tris[bis(2′-benzimidazolylmethyl) amine]-1,3,5-triazine), have been synthesized and characterized. Both complexes bind to DNA and cleave the supercoiled pUC19 plasmid DNA into its nicked and linear forms at micromolar concentrations and physiologically relevant conditions. The DNA cleavage efficacy of 1 is higher than that of 2 though its DNA binding ability is lower than the latter. The cleavage mechanism in the presence of hydrogen peroxide appears to be different for 1 and 2.
Keywords: Copper complex; DNA binding; Cleavage; Nuclease; Benzimidazole derivatives;

Two new enantiopure oxazolines, (S)-4-isobutyl-2-methyl-2-oxazoline (HL-1) and (S)-2-(2,2-dimethylpropyl)-4-isopropyl-2-oxazoline (HL-2), reacted with Pd(OAc)2 followed by treatment with LiCl to form the corresponding coordination complexes PdCl2(HL)2 with no traces of cyclopalladated derivatives PdCl2L2.(S)-4-Isobutyl-2-methyl-2-oxazoline (1) was obtained from ethyl acetimidate hydrochloride and l-leucinol in 81% yield. (S)-2-(2,2-Dimethylpropyl)-4-isopropyl-2-oxazoline (2) was synthesized from 3,3-dimethylbutyryl chloride and l-valinol in two steps in a total yield of 44%. Reactions of oxazolines 1 and 2 with Pd(OAc)2 in AcOH or MeCN at different temperatures followed by treatment with LiCl resulted in the formation of the corresponding coordination complexes PdCl2(1)2 and PdCl2(2)2 with no traces of cyclopalladated complexes.
Keywords: Oxazolines; Coordination complexes; Cyclopalladated complexes; Six-membered palladacycles;

First donor stabilized-phosphenium rhodium complexes by Jacques Andrieu; Michèle Azouri; Philippe Richard (1401-1404).
Synthesis of first donor stabilized-phosphenium rhodium complexes, which exhibit electrostatic interactions between the chloride atom and the imidazolium rings as well as a moderated basicity of the cationic P-ligand is described.The coordination properties of a donor stabilized-phosphenium adduct have been examined in rhodium chemistry. The preparation as well as the characterization of the first examples of donor stabilized-phosphenium rhodium(I) complexes is reported in this paper. Indeed, mono- and di-cationic rhodium complexes were obtained in quantitative yield by the direct addition of this imidazolium P(III)-ligand to [RhCl(1,5-COD)]2 in CH2Cl2 solution with a 1:1 P/Rh ratio under argon and 2:1 P/Rh ratio under CO atmosphere, respectively. Crystal structure of the bis-cationic donor stabilized-phosphenium rhodium(I) complex has been obtained from an acetone/pentane mixture. Its molecular structure has revealed a particular arrangement in which the chloride atom is sandwiched between both imidazolium rings as a result of the electrostatic attractive interactions between the electron-deficient heterocarbene moieties and the electron rich halide atom. On the other hand, the basicity of N-donor-phosphenium adducts has been evaluated by measure of the CO stretching frequency in one rhodium complex, and was found halfway between the phosphites and the strong π-acceptor phosphines.
Keywords: Phosphenium; Donor–acceptor ligand; Rhodium; Phosphine and electronic properties;

Reactions of ZnII nitrate with a rigid ligand tetrabromoterephthalic acid (H2TBTA) under different solvents afford a 1-D chain complex and a 2-D coordination framework with kgm network topology, which reveals the critical role of solvents on tuning the network structures of coordination polymers.Two distinct coordination polymers [Zn(TBTA)(DMF)2(CH3OH)2] n (1) and {[Zn(TBTA)0.5(DMF)(OH)]-(H2O)} n (2) have been prepared from the vapor diffusion reactions of ZnII nitrate with a rigid ligand tetrabromoterephthalic acid (H2TBTA) under different solvent atmospheres. Both complexes have been characterized by elemental analysis, IR, powder X-ray diffraction, and TG-DTA techniques. Single crystal-X-ray diffraction studies reveal that 1 displays a 1-D linear motif with TBTA spacers whereas 2 presents a 2-D kgm network with the aid of hydroxyl spacers and 4-connected TBTA linkers.
Keywords: Coordination polymer; Solvent-controlled synthesis; ZnII tetrabromoterephthalate; Network topology;

Construction of three isostructural 3d–4f microporous coordination frameworks based on mixed nicotinate and oxalate ligands by Guo Peng; Yong-Cai Qiu; Zhi-Hui Liu; Ying-Hua Li; Biao Liu; Hong Deng (1409-1411).
Three unusual 3D 3d–4f coordination polymer, [LnCu(nic)2(ox)] ·  xH2O [Ln = La, x  = 1 (1); Ln = Eu, x  = 2 (2); Ln = Gd, x  = 2 (3)] [ox = oxalate, nic = nicotinate] have been successfully synthesized. All three structures exhibit same unusual 3D microporous heterometallic coordination frameworks that are built up by rare tetranuclear Ln2Cu2 clusters and mixed ox and nic linkers. Furthermore, the fluorescent property of complex 2 has been investigated.The self-assembly of nicotinic acid and sodium oxalate with mixed 3d–4f metal salts under hydrothermal conditions gave three isostructural 3D 3d–4f coordination polymers, [LnCu(nic)2(ox)] ·  xH2O [Ln = La, x  = 1 (1); Ln = Eu, x  = 2 (2); Ln = Gd, x  = 2 (3)] [ox = oxalate, nic = nicotinate]. All three structures exhibit same unusual 3D microporous heterometallic coordination frameworks that are built up by rare tetranuclear Ln2Cu2 clusters and mixed ox and nic linkers. Furthermore, the luminescent property of complex 2 has also been investigated.
Keywords: Hydrothermal synthesis; Isostructures; Ln2Cu2 cluster; Luminescence;

Metal–organic hybrid networks constructed with the 4,4′-bisimidazolylbiphenyl ligand by Liangming Hu; Brian E. Hanson; Carla Slebodnick; Elinor C. Spencer (1412-1416).
The ligand 4,4′-bisimidazolylbiphenyl has been used to prepare three new 2D hybrid networks. Compound 1 is a copper(II) network, whereas compounds 2 and 3 are nickel-based hybrid networks of different topologies. The crystal structures for all three complexes are reported.The ligand 4,4′-bisimidazolylbiphenyl has been used to prepare three new 2D hybrid networks: (C18H14N4)CuSO4  · H2O (1), (C18H14N4)2Ni(H2PO3)2 (2), and (C18H14N4)3Ni3(H2PO4)2(HPO4)2  · 4H2O (3). All structures have been fully elucidated by single-crystal X-ray diffraction. The 2D hybrid sheets in crystal structures of complexes 1 and 2 are packed in simple AAA stacking arrangement. Conversely, in 3 the sheets are interdigitated. The topologies of the two nickel-based networks are strongly dependant on the nature of the acid employed in the synthesis procedure.
Keywords: Hybrid materials; Copper(II); Nickel (II); Hydrothermal synthesis; Metal–organic network;

Unsymmetrical 3- and 5-substituted bis(pyrazolyl)borate system by H.V.Rasika Dias; Giancarlo Gioia Lobbia; Grazia Papini; Maura Pellei; Carlo Santini (1417-1418).
An unsymmetrical 3- and 5-substituted bis(azolyl)borate system, the sodium dihydrobis(3-trifluoromethyl-pyrazol-1-yl)(5-trifluoromethyl-pyrazol-1-yl)borate, Na[H2B(3-(CF3)pz)(5-(CF3)pz)], has been synthesized by the reaction of 3-trifuoromethyl-pyrazole with Na[H3B(5-(CF3)pz)] in toluene solution. Na[H2B(3-(CF3)pz)(5-(CF3)pz)] reacts with AgNO3 in the presence of triphenylphosphine to afford the silver(I) bis(phosphane) adduct {[H2B(3-(CF3)pz)(5-(CF3)pz)]Ag[P(C6H5)3]2}. Solid state structure of {[H2B(3-(CF3)pz)(5-(CF3)pz)]Ag[P(C6H5)3]2} features a κ2-N,N′ bonded bis(pyrazolyl)borate ligand and a pseudo-tetrahedral silver center.An unsymmetrical 3- and 5-substituted bis(azolyl)borate system, the sodium dihydrobis(3-trifluoromethyl-pyrazol-1-yl)(5-trifluoromethyl-pyrazol-1-yl)borate, Na[H2B(3-(CF3)pz)(5-(CF3)pz)], has been synthesized by the reaction of 3-trifuoromethyl-pyrazole with Na[H3B(5-(CF3)pz)] in toluene solution. Na[H2B(3-(CF3)pz)(5-(CF3)pz)] reacts with AgNO3 in the presence of triphenylphosphine to afford the silver(I) bis(phosphane) adduct {[H2B(3-(CF3)pz)(5-(CF3)pz)]Ag[P(C6H5)3]2}. These compounds have been characterized by elemental analyses, FT-IR, ESI-MS and multinuclear NMR spectroscopy. Solid state structure of {[H2B(3-(CF3)pz)(5-(CF3)pz)]Ag[P(C6H5)3]2} is also reported. It features a κ2-N,N′ bonded bis(pyrazolyl)borate ligand and a pseudo-tetrahedral silver center.
Keywords: Silver(I); Scorpionates; X-ray; Phosphanes; Spectroscopy;