Inorganic Chemistry Communications (v.10, #8)

Contents List (iii-x).

Phenylcalcium iodides with silyl substituents in para-position by Jens Langer; Helmar Görls; Matthias Westerhausen (853-855).
Arylcalcium halides, which may be regarded as heavy Grignard reagents, are gaining on importance and generality which is a requirement for the implementation of these highly reactive compounds in synthetic organic and organometallic chemistry.The reduction of silyl substituted iodobenzenes 4-Ph3Si–C6H4–I (1) and Me2Si(–C6H4–4–I)2 (2) with activated calcium yields sparingly soluble 4-Ph3Si–C6H4–Ca(thf)4I (3) and moderate soluble Me2Si[–C6H4–4-Ca(thf)4I]2 (4). The molecular structures of 1 and 2 and a structural motif of 4 are presented.
Keywords: Calcium; Direct synthesis; Grignard reagents; Organocalcium compounds; Phenylcalcium iodide;

Six-, seven- and eight-coordinated Cd(II) ions with N-heterocyclic multicarboxylic acids by Hong-Sheng Wang; Wei Shi; Jun Xia; Hai-Bin Song; Hong-Gen Wang; Peng Cheng (856-859).
Cd(II) ions in two complexes with 2,4,6-pyridinetricarboxylic acid and 2,3,5,6-pyrazinetetracarboxylic acid showed three different coordination numbers of six, seven and eight, respectively. The unusual high coordination numbers were rare to be found in transition metal ions.Two novel cadmium complexes [Cd3(pta)2(H2O)4] n (1) (H3pta = 2,4,6-pyridinetricarboxylic acid) and {[Cd(H2pza)(H2O)2] · 2H2O} n (2) (H4pza = 2,3,5,6-pyrazinetetracarboxylic acid) were synthesized. In both complexes, Cd(II) ions show three different coordination numbers of six and seven in 1 and eight in 2, respectively. Complex 1 displays a three-dimensional network structure and 2 shows a one-dimensional chain structure. The one-dimensional chains in 2 are vertical or parallel to each other and form a three-dimensional network structure by hydrogen bonds. In addition, 1 emits intense fluorescence on excitation of 342 nm.
Keywords: 2,4,6-Pyridinetricarboxylic acid; 2,3,5,6-Pyrazinetetracarboxylic acid; Cadmium complex; Crystal structure;

A new hydrogen-bonded charge-transfer complex [Ni(Hpydt)2]TNAP: Synthesis, structure and electrical conductivity by Sota Shibahara; Hiroshi Kitagawa; Takashi Kubo; Kazuhiro Nakasuji (860-862).
Bis(2,3-pyridinedithiolate)nickel(II) complex gives a hydrogen-bonded charge-transfer (HBCT) complex with 11,11,12,12-tetracyanonaphtho-2,6-quinodimethane (TNAP), [Ni(Hpydt)2]TNAP. This is the first example of an HBCT complex composed of TNAP. The electrical resistivity of the complex at 298 K is 640 Ω cm and the activation energy of 137 meV.Bis(2,3-pyridinedithiolate)nickel(II) complex gives a hydrogen-bonded charge-transfer (HBCT) complex with 11,11,12,12-tetracyanonaphtho-2,6-quinodimethane (TNAP), [Ni(Hpydt)2]TNAP. This is the first example of an HBCT complex composed of TNAP. The donor and acceptor components alternate within each stack. The ionicity of the each component is estimated to be ±1.0. The electrical resistivity of the complex at 298 K is 640 Ω cm and the activation energy of 137 meV.
Keywords: Hydrogen-bonded charge-transfer complex; Crystal structure; Electrical conductivity; Semiconductors; Band calculation;

Synthesis, solid-state and in-solution structures of a new seven coordinated manganese(II) complex via X-ray diffraction and electrospray ionization mass spectrometry by Josane A. Lessa; Adolfo Horn; Carlos B. Pinheiro; Lorena L. Farah; Marcos N. Eberlin; Mario Benassi; Rodrigo R. Catharino; Christiane Fernandes (863-866).
The new compound [Mn(HPClNOL)(η1-NO3)(η2-NO3)] 1 posses a seven-coordinated manganese(II) ion in solid-state, showing a N3O4 coordination environment. ESI(+)–MS/MS studies of this water soluble compound reveals that in water:methanol (1:1) solutions, the solid-state structure is not preserved, since at least four other structures were detected.The structure of the [Mn(HPClNOL)(η1-NO3)(η2-NO3)] 1 complex [HPClNOL = 1-(bis-pyridin-2-ylmethyl-amino)-3-chloropropan-2-ol] in the solid-state and in H2O/MeOH solution was investigated by monocrystal X-ray diffraction and ESI(+)–MS/MS. X-ray reveals that 1 is a seven-coordinated complex with a discrete mononuclear structure in which the manganese(II) ion is coordinated by the tripodal HPClNOL ligand and two nitrate ions, one monodentate and the other bidentate. ESI(+)–MS/MS shows that mononuclear, dinuclear and trinuclear manganese cationic species are present in solution, probably in equilibrium with neutral 1. This contrasting scenario illustrates for 1 the importance of both solid-state and in-solution characterizations of coordination compounds with potential bioinorganic interest.
Keywords: ESI(+)–MS/MS; Seven-coordinated manganese; Manganese enzyme; Synthetic model; In-solution characterization; Water soluble manganese compound;

Novel unexpected Tb3+ coordination polymer containing two carboxylate ligands: Syntheses, structure and photoluminescent properties by Ercules E.S. Teotonio; Gerson M. Fett; Hermi F. Brito; Antônio C. Trindade; Maria Cláudia F.C. Felinto (867-872).
Novel unexpected coordination polymer [Tb(PHTHGLY)(CBGLY)(H2O)2](H2O)3 complex containing simultaneously N-phthaloylglycinate and N-(2-carboxybenzoyl)glycinate ligands has been prepared. The X-ray crystal diffraction indicates that the Tb3+-complex crystallizes in a triclinic crystal system and space group P 1 ¯ , forming a 1D polymer where carboxylate groups bridge the Tb3+ ions. Photoluminescence data revel that the ligands act as efficient “antennas” sensitizing the luminescence of the Tb3+ ion.Novel unexpected coordination polymer [Tb(PHTHGLY)(CBGLY)(H2O)2](H2O)3 complex containing simultaneously N-phthaloylglycinate and N-(2-carboxybenzoyl)glycinate ligands has been prepared and characterized by single crystal X-ray structure, thermogravimetric analysis and infrared spectroscopy. The X-ray crystal diffraction indicates that the Tb3+-complex crystallizes in a triclinic crystal system and space group P 1 ¯ , forming a 1D polymer where carboxylate groups bridge the Tb3+ ions. The photoluminescence data revel that the ligands act as efficient “antennas” sensitizing the luminescence of the Tb3+ ion showing a strong green emission color arising from intraconfigurational 5D4  →  7F J transitions (J  = 0–6).
Keywords: Phthaloylcarboxylates; Terbium; Syntheses; Photoluminescence; X-ray structure;

A functionalized derivative of the Zn 7 O 2 10 + cluster compound has been synthesized and structurally characterized. It represents the first time that this cluster complex has been synthesized with pendent functionality for further reaction.A heptanuclear zinc cluster has been synthesized based on the rarely seen M 7 O 2 10 + double tetrahedron. This new cluster is monomeric in nature and is the first of its kind to display the added functionality of uncoordinated hydroxyl groups. These reactive functional groups will allow it to be used to construct designed frameworks.
Keywords: Zn clusters; Metal carboxylate; X-ray diffraction;

Solvothermal synthesis, crystal structure and photoluminescent property of a novel 3-D magnesium metal–organic framework Mg1.5(μ5-btec)(H2O)2] · [H2N(CH3)2] · H2O by Dao-Jun Zhang; Tian-You Song; Ping Zhang; Jing Shi; Ying Wang; Li Wang; Kui-Rong Ma; Wei-Rong Yin; Jie Zhao; Yong Fan; Jia-Ning Xu (876-879).
A novel 3-D magnesium metal–organic framework [Mg1.5(μ5-btec)(H2O)2] · [H2N(CH3)2] · H2O (btec = 1,2,4,5-benzenetetracarboxylic acid) has been synthesized under solvothermal conditions, and characterized by single-crystal X-ray structure determination, thermogravimetric analysis, X-ray powder diffraction, IR, and photoluminescent studies.A novel 3-D magnesium metal–organic framework [Mg1.5(μ5-btec) (H2O)2] · [H2N(CH3) 2] · H2O (btec = 1,2,4,5-benzenetetracarboxylic acid) has been synthesized under solvothermal conditions, and characterized by single-crystal X-ray structure determination, thermogravimetric analysis, X-ray powder diffraction, IR, and photoluminescent studies.
Keywords: Metal–organic framework; Crystal structure; Magnesium; Photoluminescence;

A spin gap transition around 230 K observed in a new Ni(mnt)2-based molecular solid containing 1-(4′-nitrobenzyl)isoquinolinium by Chunlin Ni; Jiarong Zhou; Zhengfang Tian; Zhaoping Ni; Yizhi Li; Qingjin Meng (880-883).
In the novel molecular solid, [ NO 2 BzIQl ] [ Ni ( mnt ) 2 - ] ( [ NO 2 BzIQl ] + = 4 -nitrobenzylisoquinolinium, mnt 2 - = maleonitriledithiolate ) , the anions and cations stack into columns in the solid state and the Ni(III) ions form a 1D zigzag alternating chain with the Ni⋯Ni distances of 3.907 Å and 3.977 Å within a Ni(mnt)2 column. Magnetic susceptibility measurements show that 1 exhibits a spin gap transition with a second-order characteristic by DSC determination around 230 K.A organic cation, [NO2BzIQl]+([NO2BzIQl]+  = 4-nitrobenzylisoquinolinium), that acts as a courterion in assembling Ni ( mnt ) 2 - (mnt2−  = maleonitriledithiolate), results in the forming of a new molecular solid [NO2BzIQl][Ni(mnt)2] (1) in which the anions and cations stack into columns in the solid state and the Ni(III) ions form a 1D zigzag alternating chain through Ni⋯S and π⋯π interactions between anions with the Ni⋯Ni distances of 3.907 Å and 3.977 Å within a Ni(mnt)2 column. Magnetic susceptibility measurements show that 1 exhibits a spin gap transition with a second-order characteristic by DSC determination around 230 K.
Keywords: Maleonitriledithiolate; 1-(4′-Nitrobenzyl)isoquinolinium; Nickel(III) complex; Crystal structure; Spin gap transition;

The crystal structures of 3,3′-bi-1,2,4-oxadiazole, a mononuclear complex with palladium(II) chloride and a 1D coordination polymer with silver(I) nitrate are reported. In both complexes coordination occurs through the N4 nitrogen atoms.The crystal structure of 3,3′-bi-1,2,4-oxadiazole (1) reveals a planar centrosymmetric structure for this molecule in the solid state. It forms a mononuclear complex (3) with palladium(II) chloride, which is shown by X-ray crystallography to contain the ligand chelated through the two N4 nitrogens. The X-ray structure of the complex (5) with silver(I) nitrate shows a one-dimensional coordination polymer in which the ligand acts in a bridging mode, again with coordination through the N4 nitrogen atoms.
Keywords: 1,2,4-Oxadiazole; Palladium; Silver; N Ligands;

Benzotriazole controlled unusual building blocks in two zinc complexes and their fluorescence properties by Yi-Cheng Shen; Zhao-Ji Li; Jian-Kai Cheng; Ye-Yan Qin; Yuan-Gen Yao (888-890).
Two novel zinc coordination polymers with unusual planar hexa-nuclear zinc unit and tetranuclear zinc(II) metallamacrocycle unit acting as building blocks, respectively, have been successfully synthesized and characterized.Two novel zinc coordination polymers with unusual planar hexa-nuclear zinc unit and tetranuclear zinc(II) metallamacrocycle acting as building blocks, respectively, have been successfully synthesized and characterized by elemental analysis, IR spectra and X-ray diffraction. The presences of quinolinecarboxylate ligand in both structures result in rich π–π interactions and strong blue fluorescent emissions at 400 nm and 397 nm, respectively at room temperature.
Keywords: Quinolinecarboxylic acid; Benzotriazole; Zinc; Metal–organic coordination polymers; Fluorescence properties;

The title compound was obtained by treatment of [UO2Cl2(THF)2]2 with NaBH4, followed by addition of hmpa; this thermally unstable complex is a catalyst in the hydroboration of substituted alkenes by NaBH4.Reaction of [UO2Cl2(THF)2]2 with NaBH4 in THF led to the formation of [UO2Cl2−x (BH4) x (THF) n ], and addition of hmpa induced the crystallization of [UO2(BH4)2(hmpa)2], whose structure exhibits the bidentate ligation mode of the borohydride ligand; this uranyl borohydride, which is thermally unstable with respect to elimination of borane, is a catalyst in the hydroboration of substituted alkenes by NaBH4.
Keywords: Uranyl; Borohydride ligands; Hydroboration; Crystal structure;

An organic–inorganic hybrid uranyl nicotinate molybdate polymer and its fluorescent property by Xiangjian Kong; Yanping Ren; Lasheng Long; Rongbin Huang; Lansun Zheng (894-896).
The hydrothermal reaction of UO2(NO3)2  · 6H2O, phosphomolybolic acid (H3PMo12O40) and nicotinic acid [Hnicot = NC5H4CO2H] produces a first organic–inorganic uranyl nicotinate molybdate polymer, [UO2(nicot)(MoO3OH)] n , which represents a 1D chain structure with strong fluorescence. In the reaction, the phosphomolybolic acid decomposes into MO3OH anion, which connects uranyl cation and nicotinic anion to form 1D chain.A uranyl nicotinate molybdate polymer [UO2(nicot)(MoO3OH)] n (Hnicot = nicotinic acid, NC5H4CO2H) was synthesized by the hydrothermal reaction of uranyl nitrate [UO2(NO3)2  · 6H2O], phosphomolybolic acid (H3PMo12O40) and nicotinic acid. Its crystal structure and fluorescent property were measured. The results show that the crystal packs in the 1D chains of uranyl molybdates with strong fluorescence at the range of 470–520 nm.
Keywords: Uranyl nicotinate molybdate; Polymer; Crystal structure; Fluorescence;

Spin-canting in a 1D chain Mn(II) complex with alternating double end-on and double end-to-end azido bridging ligands by Jian-Ying Zhang; Cai-Ming Liu; De-Qing Zhang; Song Gao; Dao-Ben Zhu (897-901).
A new 1D manganese(II) complex containing alternating double EE- and double EO-azido ligands, [Mn(dpq)(N3)2] n [dpq = dipyrido-(3,2-d:2,3-f)-quinoxaline] was synthesized and characterized. EO- and EE-azido bridges exchange ferromagnetic and antiferromagnetic interactions, respectively, and a weak ferromagnetic property due to spin canting was observed below 6 K.A new one-dimensional (1D) azido-bridged manganese(II) complex, [Mn(dpq)(N3)2] n [dpq = dipyrido-(3,2-d:2′,3′-f)-quinoxaline] (1), was synthesized and characterized. Crystal structure study reveals that 1 contains a 1D manganese(II) chain bridged by alternating double end-to-end (EE) and double end-on (EO) azido ligands. The strong interchain π–π stacking interaction extends the structure into a 2D supramolecular array. The analysis of magnetic data indicates that the EO- and EE-azido bridges mediate the ferromagnetic and antiferromagnetic interactions, respectively. Interestingly, complex 1 exhibits a weak ferromagnetic property below 6 K probably due to spin canting.
Keywords: Manganese(II) complex; Azido ligand; Coordination polymer; Spin canting; Magnetic property; Crystal structure;

A trinuclear anionic trifluoroacetato derivative of iron(II) containing a central O(–I) ligand by Alberto Albinati; Fausto Calderazzo; Fabio Marchetti; Sax A. Mason; Bernardo Melai; Guido Pampaloni; Silvia Rizzato (902-905).
The reaction of Fe(CO)5 with CF3COOH/(CF3CO)2O, or with CF3COOH, in DMF at about 140 °C produces [Fe(DMF)6][Fe33-O)(CF3COO)6(DMF)3]2, characterized by a triangular disposition of the three iron atoms, the central substantially coplanar oxygen atom being formulated as a singly charged anion O(–I) stabilized by complexation to iron(II).The reaction of Fe(CO)5 with CF3COOH/(CF3CO)2O, or with CF3COOH, in DMF at about 140 °C produces the colourless compound 1, [Fe(DMF)6][Fe33-O) (CF3COO)6(DMF)3]2, constituted by the [Fe(DMF)6]2+ cation and by two [Fe33-O)(μ2-CF3COO)6(DMF)3] anions, with a triangular disposition of the three iron atoms, the central substantially coplanar oxygen atom being formulated as a singly charged anion O(–I) stabilized by complexation to iron(II).
Keywords: Neutron-diffraction; Single crystal; Iron(II); M3O system;

The synthesis, reactivity, and the catalytic ability of an octahedrally coordinated vanadium(III) scorpionate analogue complex are reported. The title complex makes use of the monoanionic facially coordinating ligand, CpPOEtCo. (CpPOEtCo)VCl2(DMF) was found to be an effective catalyst in the oxidation of 3,5-di-tert-butyl catechol to the corresponding quinone. An X-ray crystal structure of (CpPOEtCo)VCl2(DMF) is also reported.Vanadium complexes are extensively used in the chemical industry as oxidation catalysts. During the course of our investigations into vanadium oxidation catalysis, the rich reactivity of a vanadium(III) scorpionate analogue complex, (CpPOEtCo)VCl2(DMF) (1), was investigated. The octahedrally coordinated 1 was prepared by mixing vanadium(III) chloride with Na(CpPOEtCo) in DMF. The crystal structure of 1 has been determined through X-ray diffraction. Complex 1, C20H42Cl2CoNO10P3V, crystallizes in the monoclinic space group P21/c with a  = 38.566(9) Å, b  = 9.499(2) Å, c  = 18.149(4) Å, and β  = 100.485(4)° with Z  = 8. Complex 1 was found to be an effective pre-catalyst for the oxidation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butylquinone. The reactivity studies, oxidative catalytic ability, as well as X-ray structural characterization of (CpPOEtCo)VCl2(DMF) will be discussed. ((CpPOEtCo) = [η5-cyclopentadienyltris(diethylphosphito-κ1P) cobaltate(III); DMF =  N,N-dimethylformamide).

The hydrothermal reaction of Co(NO3)2  · 6H2O and a new designed ligand H2DCNT yields a three-dimensional polymer [Co(DCNT)(H2O)] n (1), H2DCNT = 2,4-bis(4-carboxyphenylamino)-6-diethylamino-1,3,5-triazine. In the structure of 1, each DCNT2− has three coordination sites, one nitrogen atom in the triazine ring coordinating to Co(II) and two carboxylates adopting μ2-bridging mode, which make the infinite Co(II) chains array uniformly and evenly toward crystallographic c-axis. Luminescent and magnetic properties of 1 were also studied.The hydrothermal reaction of Co(NO3)2  · 6H2O and a new designed ligand H2DCNT yields a three-dimensional polymer [Co(DCNT)(H2O)] n (1), H2DCNT = 2,4-bis(4-carboxyphenylamino)-6-diethylamino-1,3,5-triazine. In the structure of 1, each DCNT2− has three coordination sites, one nitrogen atom in the triazine ring coordinating to Co(II) and two carboxylates adopting μ2-bridging mode, which make the infinite Co(II) chains array uniformly and evenly toward crystallographic c-axis. Luminescent and magnetic properties of 1 were also studied.
Keywords: Hydrothermal method; Coordination polymer; Luminescence; Magnetic property;

A polymer bound Schiff base ligand 1 was prepared and reacted with ethylene diamine. The functionalized polystyrene 2 was used to immobilize Mo(CO)6 and polymer bound molybdenum carbonyl Schiff base catalyst 3 was produced. This supported catalyst shows high activity in epoxidation of various alkenes in the presence of tert-buthylhydroperoxide (TBHP), which then can be recovered and reused for eight times without loss of its activity.Polymer-bound Schiff base ligand 2 was prepared by oxidation of chloromethylated polystyrene to aldehydic polystyrene 1 and then reaction with ethylene diamine. The functionalized polystyrene 2 was used to immobilize Mo(CO)6 and polymer-bound molybdenum carbonyl Schiff base catalyst 3 was produced. This supported catalyst shows high activity in epoxidation of various alkenes in the presence of tert-butylhydroperoxide (TBHP). The supported molybdenum catalyst can be recovered and reused for eight times without loss in its activity.
Keywords: Polymer-support; Molybdenum carbonyl; Schiff base complex; Epoxidation;

The reaction of the [ReOBr3(PPh3)2] complex with 2,2′:6′,2″-terpyridine (terpy) in the presence of tripenylphosphine has been examined and novel [ReBr(terpy)(PPh3)2]ReO4  · H2O · CH3OH complex – has been obtained. It has been studied by IR, UV–vis spectroscopy and X-ray crystallography.The reaction of the [ReOBr3(PPh3)2] complex with 2,2′:6′,2″-terpyridine (terpy) in the presence of tripenylphosphine has been examined and novel [ReBr(terpy)(PPh3)2]ReO4  · H2O · CH3OH complex – has been obtained. It has been studied by IR, UV–vis spectroscopy and X-ray crystallography.
Keywords: Rhenium(II) complexes; 2,2′:6′,2″-Terpyridine; X-ray structure; Electronic structure;

Microwave assisted hydrothermal synthesis of a novel CuI-sulfate-pyrazine MOF by Pilar Amo-Ochoa; Gonzalo Givaja; Pablo J. Sanz Miguel; Oscar Castillo; Félix Zamora (921-924).
A very fast crystallization process of a novel 3D Cu(I) coordination polymer by using microwave irradiation is reported. The result is compared with that obtained under conventional hydrothermal conditions. These results could be valuable for the future preparations of MOFs in large scale.A new 3D coordination copper polymer has been synthesised under microwave heating hydrothermal conditions. Microwave irradiation reduces the time of reaction considerably, suggesting the effectiveness of this methodology in the synthesis of metal-organic frameworks. It is noteworthy that microwave assisted synthesis produces monocrystals suitable for X-ray diffraction studies, reducing reaction time and with higher yield than the classical hydrothermal procedures. The compound presented here, [Cu2(pyz)2(SO4)(H2O)2] n (pyz = pyrazine), has been crystallographically characterised to be a threefold interpenetrated three-dimensional coordination (10,3)-b network.
Keywords: Coordination polymer; Interpenetrating networks; Microwave synthesis; Hydrothermal synthesis; MOF;

Sensing metal ions with two new azomethine–thiophene pincer ligands (NSN): Fluorescence and MALDI-TOF-MS applications by Bruno Pedras; Hugo M. Santos; Luz Fernandes; Berta Covelo; Abel Tamayo; Emilia Bértolo; José Luis Capelo; Teresa Avilés; Carlos Lodeiro (925-929).
The two new pincer azomethine–thiophene ligands and their absorption, fluorescence and MALDI-TOF-MS spectroscopic studies are described. The two systems synthesised combine the emissive probes pyrene and naphthyl with the good chelating properties of a tridentate SN2 donor-atoms from a thiophene Schiff-base ligand. The bichromophoric pyrene derivative presents two emission bands in solution, one corresponding to the monomer species and a red-shifted band attributable to the intramolecular excimer. Ni(II) and Pd(II) complexation affects the conformation in solution, increasing the monomer emission at the expense of the excimer band; this effect could be explored in metal ion sensing. System L1 behaves as non emissive probe. In situ complexation reactions followed by MALDI-TOF-MS spectrometry without matrix support have also been performed; these experiments show that L1 could be a potential chemosensor for Ni(II) and Pd(II).The two new pincer azomethine–thiophene ligands (N,NE′,N,NE′)-N,N′-(thiophene-2,5-diylbis(methan-1-yl-1-ylidene))bis(naphathalen-2-ylmethanamine) (L1) and (E)-(4,6-dihydropyren-1-yl)-N-((5-((E)-(pyren-1-ylmethylimino)ethyl)thiophen-2-yl)methylene)methanamine (L2), their absorption, fluorescence and MALDI-TOF-MS spectroscopic studies are described. The two systems synthesised combine the emissive probes pyrene and naphthyl with the good chelating properties of a tridentate SN2 donor-set from a thiophene Schiff-base ligand. Both ligands gave analytically pure solid complexes with Ni(II) and Pd(II) salts. The bichromophoric pyrene derivative L2 presents two emission bands in solution, one corresponding to the monomer species and a red-shifted band attributable to the intramolecular excimer. Ni(II) and Pd(II) complexation affects the conformation in solution, increasing the monomer emission at the expense of the excimer band; this effect could be explored in metal ion sensing. System L1 behaves as a non emissive probe. In situ complexation reactions followed by MALDI-TOF-MS spectrometry without matrix support have also been performed; these experiments show that L1 could be a potential chemosensor for Ni(II) and Pd(II).
Keywords: Nickel(II); Palladium(II); Thiophene; Fluorescent chemosensors; MALDI-TOF-MS;

Synthesis and physico-chemical characterization of [Hf(NEt2)2Cl2(DME)] and its use as catalyst for ethylene polymerization by Giovanni Carta; Gilberto Rossetto; Franco Benetollo; Pierino Zanella; Gianni Cavinato (930-932).
The new solid-state complex [Hf(NEt2)2Cl2(DME)], intermediate in the synthesis of the new bis-diethylamide bis-isopropoxy hafnium (IV) complex [Hf(NEt2)2(O i Pr)2] has been synthesized and characterized by NMR spectroscopy and X-ray diffraction. The dichloride complex was tested as a catalyst for ethylene polymerization showing a low activity, but giving high density polyethylenes.The new solid-state complex {[Hf(NEt2)2Cl2(DME)] (DME = 1,2-dimethoxyethane)}, intermediate in the synthesis of the new bis-diethylamide bis-isopropoxy hafnium (IV) complex [Hf(NEt2)2(O i Pr)2], has been synthesized, isolated and characterized by NMR spectroscopy and X-ray diffraction. The crystal structure showed the metal to be hexa-coordinated with a distorted octahedral geometry. Catalytic tests for the polymerization of ethylene have been carried out using this intermediate with [(NHMe2Ph)B(C6F5)4] as cocatalyst. The obtained polymer had a high molecular weight and a high melting point, characteristic of a high density polyethylene (HDPE).
Keywords: Alkylamide-alkoxy hafnium complexes; Crystal structure; Polyethylene; HDPE;

A Dawson structure cluster anion based on VVO4 tetrahedra has been isolated from an aqueous solution and was characterized by single-crystal X-ray structure analysis, XRD, IR, 51V NMR, and TG. The electrochemical behaviors of this compound have been investigated.A conventional Dawson structure polyoxomolybdovanadate cluster anion based on VVO4 tetrahedra, [Mo18O54(VO4)2]6− (1a), has been isolated from an acidified aqueous solution with the presence of triethanolamine (TEA) in the condition of heated refluence, and was characterized by single-crystal X-ray structure analysis, XRD, IR, and TG. The 51V NMR spectrum indicates that the two V atoms in 1a have the same coordination environments. The electrochemical behaviors of this compound have been investigated.
Keywords: Polyoxomolybdovanadates; Polyoxometalates; Dawson; 51V NMR spectrum; Electrochemical behaviors;

New water and orotate bridged polynuclear seven-coordinated potassium complex, [K(μ5-H2Or)(μ-H2O)] n (H3Or = orotic acid), with unprecedented coordination mode of orotic acid has been prepared and characterized.Novel polynuclear seven-coordinated potassium complex, [K(μ5-H2Or)(μ-H2O)] n (H3Or = orotic acid), with the new coordination mode of orotic acid has been prepared and characterized by elemental analysis, FT-IR spectra, X-ray diffraction. The orotate ligand exhibits new coordination mode of μ5-κO, O: κO′, O′: O″ for H2Or.
Keywords: Orotic acid; New coordination mode; Potassium orotate; Vitamin B13;

A novel three-dimensional cyano-bridged complex {Ni(Me6-[14]ane-N4)}2[W(CN)8] · 6H2O was synthesized and characterized by IR, elemental analysis, ICP, TGA and SC-XRD. Magnetic behavior of the complex shows a characteristic of combination of zero-filed splitting of Ni2+ in axially distorted octahedral surrounding and a weak antiferromagnetic interaction between Ni2+ ions through the diamagnetic [W(CN)8]4− bridges.Self-assembly of [W(CN)8]4− and {Ni(Me6-[14]ane-N4)}2+ (Me6-[14]ane-N4  = 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) leads to a novel three-dimensional cyano-bridged complex {Ni(Me6-[14]ane-N4)}2[W(CN)8] · 6H2O (1), which was characterized by IR, elemental analysis, ICP, TGA and SC-XRD. Magnetic behavior of the complex shows a characteristic of combination of zero-field splitting of Ni2+ in an axially distorted octahedral surrounding and a weak antiferromagnetic interaction between Ni2+ ions through the diamagnetic [W(CN)8]4− bridges.
Keywords: Octacyanotungstate; Nickel(II) complex; Crystal structure; Magnetic properties;

Despite the antiferromagnetic interaction, the tilts of local distortion axes around cobalt(II) ions caused an increase in magnetic susceptibility below 20 K, which had been assumed to be caused by a paramagnetic impurity.A pair of dinucleating ligands sym-hmp [sym-hmp: 2,6-bis[(2-hydroxyethyl)methylaminomethyl]-4-methylphenolate] incorporated two cobalt(II) ions to form a dinuclear cobalt(II) complex [Co2(sym-hmp)2](BPh4)2 (1). Magnetic susceptibility indicated the antiferromagnetic exchange interaction; however, the susceptibility increased again below 20 K. Usually, such an increase is assumed to be caused by a paramagnetic impurity. However, the tilts of local distortion axes around cobalt(II) ions were found to cause the increase despite the antiferromagnetic interaction.
Keywords: Dinuclear cobalt(II) complex; Dinucleating ligand; Crystal structure; Magnetic studies;

Two-way synthesis of a double-lantern heterobimetallic complex [Pd(μ-OOCMe)4Co]2(μ-OOCMe)2Pd(py)2 by Sergei E. Nefedov; Ilya A. Yakushev; Natalia Yu. Kozitsyna; Zhanna V. Dobrokhotova; Vladimir N. Ikorsky; Michael N. Vargaftik; Ilya I. Moiseev (948-951).
The lantern complex PdII(μ-OOCMe)4CoII(NCMe) (1) was transformed into the pentanuclear double-lantern acetate-bridged heterobimetallic complex [Pd(μ-OOCMe)4Co]2(μ-OOCMe)2Pd(py)2 (2) by two routes: (i) reaction of 1 with pyridine and (ii) reaction of 1 with trans-Pd(py)2(OOCMe)2. Complex 2 was characterised by the single-crystal X-ray diffraction, DTA-TG and magnetic susceptibility data.The lantern complex PdII(μ-OOCMe)4CoII(NCMe) (1) was transformed into the pentanuclear double-lantern acetate-bridged heterobimetallic complex [Pd(μ-OOCMe)4Co]2(μ-OOCMe)2Pd(py)2 (py is pyridine) (2) by two routes: (i) reaction of 1 with pyridine and (ii) reaction of 1 with trans-Pd(py)2(OOCMe)2. Complex 2  × 3C6H6 was characterised by single-crystal X-ray diffraction, DTA-TG and magnetic susceptibility data.
Keywords: Heterobimetallic acetate complexes; Palladium; Cobalt; Pyridine; X-ray structure; Magnetic susceptibility; Thermogravimetry;

2-Hydroxy-4-methylazobenzene (HO–C6H3-p-Me-o-N=N–C6H5, 1) reacts with SiCl4 to yield the [4+4]-coordinate silicon complex 2 [Si(O–C6H3-p-Me-o-N=N–C6H5)4]. Compound 2 represents the first structurally characterized Si-complex bearing o-diazophenoxy ligands. Its X-ray structure and 29Si NMR data indicate a capped tetrahedral coordination sphere of the Si-atom.2-Hydroxy-5-methylazobenzene (HO–C6H3-p-Me-o-N=N–C6H5, 1) reacts with SiCl4 in the presence of triethylamine to yield the [4+4]-coordinate silicon complex 2 [Si(O–C6H3-p-Me-o-N=N–C6H5)4]. Its molecular structure has been determined by X-ray crystallography, and 2 represents the first structurally characterized Si-complex bearing o-diazophenoxy ligands. 29Si NMR data suggest that the capped tetrahedral coordination sphere of the Si-atom is retained in solution. Even the difluorocompound 3 [F2Si(O–C6H3-p-Me-o-N=N–C6H5)2] still exhibits a tetracoordinate Si-atom, whereas 4 [F2B(O–C6H3-p-Me-o-N=N–C6H5)], the byproduct of the formation of 3 from 2, bears a bidentate chelating o-phenyldiazo-p-methylphenoxy ligand.
Keywords: Azobenzene; Boron; Chelate; Hypercoordination; Silicon;

A trinuclear platinum–cobalt acetate-bridged complex {PtII(acac)}2CoII(μ-OOCMe)4: Synthesis and structure by Natalia Yu. Kozitsyna; Alexander E. Gekhman; Sergei E. Nefedov; Michael N. Vargaftik; Ilya I. Moiseev (956-958).
Reaction of the platinum(II) acetylacetonate Pt(acac)2 with Co(OOCMe)2  · 4H2O in air produced the PtII–CoII heterodimetallic complex {PtII(acac)}2CoII(μ-OOCMe)4 as established by single-crystal X-ray diffraction.Reaction of the platinum(II) acetylacetonate Pt(acac)2 with Co(OOCMe)2  · 4H2O in air produced the PtII–CoII heterodimetallic complex {PtII(acac)}2CoII(μ-OOCMe)4 as established by single-crystal X-ray diffraction.
Keywords: Platinum; Cobalt; Heterodimetallic complex; Acetate-bridging complex; X-ray structure;

Role of nitro-substituent in pseudo-polymorphism and in synthesis of metal carboxylato complexes of copper, zinc and manganese by Anirban Karmakar; Kusum Bania; Abhilasha M. Baruah; Jubaraj B. Baruah (959-964).
The pseudo-polymorphism and synthesis of 2-nitrobenzoato complexes of copper(II) is demonstrated and the results are compared with analogous first row transition metal carboxylato complexes.The consequence of nitro-group attached to aromatic ring of 2-nitrobenzoato complexes of copper(II) on pseudo-polymorphism and in synthesis of metal carboxylato complexes is demonstrated and the results are compared with analogous first row transition metal carboxylato complexes.
Keywords: 3d-Metal carboxylates; 2-Nitrobenzoato ligand; Polymorphism; Crystal structure; Aqua-bridged complexes; Paddle-wheel structure;