inorganic-community

Synthesis, structures, spectral and electrochemical properties of copper(II) complexes of sterically hindered Schiff base ligands

2009-05-25T20:27:00.003+07:00

Karuppasamy Sundaravel a, Eringathodi Suresh b, Mallayan Palaniandavar a,*
a School of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, Tamilnadu, India
b Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, Bhavnagar 364 002, India

a r t i c l e i n f o
Article history:
Received 28 July 2007
Received in revised form 6 March 2008
Accepted 17 March 2008
Available online 25 March 2008
Keywords:
Schiff base ligands
Copper(II) bis-ligand complexes
X-ray structures
Steric hindrance
Square planar geometry
EPR spectra

a b s t r a c t
The Schiff base ligands 2-(2,6-diisopropylphenyliminomethyl)phenol H(L1), 5-diethylamino-2-(2,6-diisopropylphenyliminomethyl)phenol H(L2), 2,4-di-tert-butyl-6-(2,6-diisopropylphenyliminomethyl) phenol H(L3), 3-(2,6-diisopropylphenyliminomethyl)naphthalen-2-ol H(L4) and 4-(2,6-diisopropylphenyliminomethyl)-5-hydroxymethyl-2-methylpyridin-3-ol H(L5) have been synthesized by the condensation, respectively, of salicylaldehyde, 4-(diethylamino)salicylaldehyde, 3,5-di-tert-butylsalicylaldehyde, 2-hydroxy-1-napthaldehyde and pyridoxal with 2,6-diisopropylaniline. The copper(II) bisligand complexes [Cu(L1)2] 1, [Cu(L2)2] 2, [Cu(L3)2] 3, [Cu(L4)2] 4 and [Cu(L5)2].CH3OH 5 of these ligands have been isolated and characterized. The X-ray crystal structures of two of the complexes [Cu(L1)2] 1 and [Cu(L5)2].CH3OH 5 have been successfully determined, and the centrosymmetric complexes possess a CuN2O2 chromophore with square planar coordination geometry.

The frozen solution EPR spectra of the complexes reveal a square-based CuN2O2 chromophore, and the values of gll and gll/All index reveal enhanced electron delocalization by incorporating the strongly electron-releasing –NEt2 group (2) and fusing a benzene ring on sal-ring (4). The Cu(II)/Cu(I) redox potentials of the Cu(II) complexes reveal that the incorporation of electron-releasing –NEt2 group and fusion of a benzene ring lead to enhanced stabilization of Cu(II) oxidation state supporting the EPR spectral results. The hydrogen bonding interactions between the two molecules present in the unit cell of 5a generate an interesting two-dimensional hydrogen-bonded network topology.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis, structure, and catalytic ethylene oligomerization of nickel(II) and cobalt(II) complexes with symmetrical and unsymmetrical 2,9-diaryl-1,10

2009-05-25T20:24:00.002+07:00

Peiju Yang a, Yue Yang a,d, Cui Zhang a,d, Xiao-Juan Yang a,*, Huai-Ming Hub, Yici Gao c, Biao Wua,*
a State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China
b Department of Chemistry, Northwest University, Xi’an 710069, China
c College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China
d Graduate University of Chinese Academy of Sciences, Beijing 100049, China
a r t i c l e i n f o

Article history:
Received 27 April 2007
Received in revised form 28 February 2008
Accepted 5 March 2008
Available online 18 March 2008
Keywords:
Nickel(II)
Cobalt(II)
1,10-Phenanthroline
Ethylene oligomerization

a b s t r a c t
A series of nickel(II) and cobalt(II) complexes, NiX2L (X = Cl, Br; 1–6) and CoCl2L (7–9), with 2,9-diaryl- 1,10-phenanthroline ligands (L1–L3) have been synthesized and characterized by elemental analysis, UV–Vis, IR spectroscopy, and X-ray crystal structural study (for 1, 4–7, 9). The solid-state structures of
1, 5–7 and 9 show four-coordinate, slightly .attened tetrahedral geometry at the Ni(II) or Co(II) center, while 4 is five-coordinated (square-pyramidal), containing a THF molecule as an auxiliary ligand. The title complexes (1–9) display good catalytic activities in ethylene oligomerization when activated with methylaluminoxane (MAO). While the Co(II) precatalysts produce primarily C4 isomers, the Ni(II) complexes give ethylene dimers and trimers at normal pressure. The activities and yields of linear a-ole.ns increase with increasing ethylene pressure for the Ni(II) complexes, leading to more high-molar-mass products (C8–C18). Complex 6 displays the best catalytic activity among the complexes studied (up to 1518 kg/ mol[Ni] h at 10 atm).
_ 2008 Elsevier B.V. All rights reserved
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Synthesis, spectral properties and supramolecular dimerisation of heteroleptic triple-decker phthalocyaninato complexes with one outer crown-substitut

2009-05-25T20:23:00.004+07:00

Alexander G. Martynov a,b, Olga V. Zubareva b, Yulia G. Gorbunova a,b,*,
Sergey G. Sakharov a, Aslan Yu. Tsivadze a,b
a N.S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Science, Leninskiy pr. 31, 119991 Moscow, Russia
b A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Science, Leninskiy pr. 31, 119991 Moscow, Russia

Received 29 August 2007; received in revised form 10 January 2008; accepted 14 January 2008
Available online 19 January 2008

Abstract
Four complexes – [(15C5)4Pc]M(Pc)M(Pc), (Pc2-– phthalocyaninato-dianion, [(15C5)4Pc]2-– 2,3,9,10,16,17,24,25-tetrakis(15-crown-5)phthalocyaninato-dianion, M = Sm, Dy, Tm, Y) were obtained via the reaction of M(Pc)2,H2[(15C5)4Pc] and M(acac)3. The influence of the stability of starting M(Pc)2 on the yields of target compounds was investigated. Increasing the stability of M(Pc)2 leads to higher yields of [(15C5)4Pc]M(Pc)M(Pc) and lower yields of scrambling products. All complexes were characterized by 1H NMR, UV–Vis and FT-IR spectroscopy as well as MALDI TOF mass-spectrometry. The analysis of 1H NMR spectra was performed in terms of lanthanide-induced shifts. Cation-induced dimerisation was studied by means of spectrophotometric titration. Supramolecular dimers {2[(15C5)4Pc]M(Pc)M(Pc).4K+} are the largest discrete cofacial supramolecular assemblies built of phthalocyanine building blocks reported up-to-date. The observed increase of the intermolecular excitonic interaction between building blocks with the increase of REE(III) size is tentatively explained in terms of metal-size dependent deformation of phthalocyanine ligands in sandwich complexes.
_ 2008 Elsevier B.V. All rights reserved.
Keywords: Rare earths; Macrocyclic ligands; Phthalocyanines; Heteroleptic complexes; Supramolecular dimerisation

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Synthesis, crystal structures and spectroscopic properties of copper(I) complexes containing b-dialdiminato supporting ligands

2009-05-25T20:22:00.003+07:00

Xiaowei Li a,b,c, Junqiao Ding b,c, Weiqun Jin a, Yanxiang Cheng b,c,*
a Department of Chemistry, Jilin University, Changchun 130012, PR China
b State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences,
Changchun 130022, PR China
c Graduate School of the Chinese Academy of Sciences, Beijing 100039, PR China

Received 11 January 2007; received in revised form 4 June 2007; accepted 12 June 2007
Available online 29 June 2007
Dedicated to Professor Michael F. Lappert

Abstract
Two mononuclear neutral copper(I) complexes, Cu(L1)PPh3 (1), Cu(L2)(PPh3)2 (2) ([L1]- = [{N(C6H3iPr2-2,6)C(H)}2CPh]-;[L2]- = [{N(C6H5)C(H)}2CPh]-) have been synthesized and structurally characterized by X-ray crystallography. In complex 1, the copper(I) atom is in a distorted three-coordinate trigonal planar environment, whereas in complex 2 with the less sterically hindered b-dialdiminato ligand, the copper(I) atom is the centre of a four-coordinate distorted tetrahedron. At room temperature complexes 1 and 2 in a .lm of PMMA exhibit green emission at 543 and 549 nm with lifetimes of 5.28 and 5.32 ns, respectively.
_ 2007 Elsevier B.V. All rights reserved.
Keywords: Copper(I) complexes; Crystal structures; b-Dialdiminatoes; Triphenylphosphine; Photoluminescence

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Synthesis, crystal structure, and properties of supramolecular CuII, ZnII, and CdII complexes with Salen-type bisoxime ligands

2009-05-25T20:17:00.003+07:00

Wen-Kui Dong *, Yin-Xia Sun, Yan-Ping Zhang, Li Li, Xue-Ni He, Xiao-Lu Tang
School of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China

a r t i c l e i n f o
Article history:
Received 31 January 2008
Received in revised form 10 March 2008
Accepted 10 March 2008
Available online 1 October 2008
Keywords:
Salen-type ligand
Transition metal complex
Synthesis
Crystal structure
Properties

a b s t r a c t
Three new supramolecular complexes, [Cu(L1)H2O]n (1), [Zn(L2)(H2O)2]n (2), and [Cd(L2)(H2O)2]n (3), have been synthesized and characterized by FT-IR spectra, fluorescence spectra, and thermal analyses. And the structures of complexes 1–3 have been elucidated by X-ray analyses. Complex 1 is square pyramidal geometry with an unusually long bond (2.262 Å) from penta-coodinated CuII center to the oxygen atom of the apical coordinated water molecule. Molecules are linked by hydrogen bonding between the coordinated water and the phenolic oxygen atoms of adjacent molecules, thus formed a self-assembling continual
zigzag chain supramolecular structure. The crystal structure of complex 2 (or 3) has indicated that the complex consists of one ZnII (or CdII) atom, one L2- unit and two coordinated water molecules, the coordination number of the ZnII (or CdII) atom is six, and formed an in.nite metal–water chain supramolecular
structure by intermolecular hydrogen bonds and π–π stacking of neighboring benzene rings. Meanwhile, the thermal and photophysical properties of the resulted complexes have also been discussed.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis, characterizations, and crystal structure of a novel layered phosphonate: Zn2Cl[O3PCH2N(CH2CH2)2O][O3PCH2NH(CH2CH2)2O]

2009-05-25T20:14:00.001+07:00

Yan-Yu Zhu, Jing Li, Zhen-Gang Sun *, Jing Zhang, Yan Zhao, Na Zhang, Lei Liu, Xin Lu
Institute of Chemistry for Functionalized Materials, Faculty of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, PR China

a r t i c l e i n f o
Article history:
Received 29 August 2008
Accepted 22 October 2008
Available online 31 October 2008
Keywords:
Metal phosphonates
Crystal structure
Hydrothermal synthesis
Zinc

a b s t r a c t
A novel layered zinc phosphonate, Zn2Cl[O3PCH2N(CH2CH2)2O][O3PCH2NH(CH2CH2)2O] 1 has been synthesized by hydrothermal reaction at 180oC and structurally characterized by single crystal X-ray diffraction as well as with infrared spectroscopy, elemental analysis and thermogravimetric analysis. The interconnection of Zn(1)O4, Zn(2)O2NCl and CPO3 tetrahedra via corner-sharing forms a double layer structure with a channel system along b-axis direction. The result of connections in this manner is the formation of 8- and 16-atom windows that are parallel to one another and run in the a-axis direction. The morpholinyl groups of the ligands are orientated toward the interlayer space.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis, characterization, and cytotoxicity of trimethylplatinum(IV) complexes with 2-thiocytosine and 1-methyl-2-thiocytosine ligands

2009-05-25T20:13:00.001+07:00

Cornelia Vetter a, Christoph Wagner a, Goran N. Kaluderovic´ a,b, Reinhard Paschke c, Dirk Steinborn a,*
a Institut für Chemie, Anorganische Chemie, Martin-Luther-Universität Halle-Wittenberg, D-06120 Halle, Kurt-Mothes-Straße 2, Germany
b Department of Chemistry, Institute of Chemistry, Technology and Metallurgy, Studentski trg 14, 11000 Belgrad, Serbia
c Biozentrum, Martin-Luther-Universität Halle-Wittenberg, D-06120 Halle, Weinbergweg 22, Germany

a r t i c l e i n f o
Article history:
Received 7 January 2008
Received in revised form 12 March 2008
Accepted 17 March 2008
Available online 24 March 2008
Keywords:
Platinum complexes
Thionucleobases
Single-crystal X-ray diffraction analysis
In vitro cytotoxic studies
DFT calculations

a b s t r a c t
The reaction of [PtMe3(MeOH)(bpy)][BF4] (1) with the thionucleobases 2-thiocytosine (SCy, 2) and 1- methyl-2-thiocytosine (1-MeSCy, 3) resulted in the formation of the complexes [PtMe3(bpy)(SCyjS)][ BF4] (4) and [PtMe3(bpy)(1-MeSCy-jS)] [BF4] (5), respectively. The complexes were characterized by 1H and 13C NMR spectroscopy as well as by single-crystal X-ray analyses of 4MeOH and 5. In 4MeOH two strong hydrogen bonds (N4–H…N30: N4…N30 2.976(7) Å) between the thiocytosine ligands give rise to base pairing thus forming dinuclear cations [{PtMe3(bpy)(SCy-jS)}2]2+. In both complexes the platinum atom is octahedrally coordinated [PtC3N2S] by three methyl ligands, the 2,20-bipyridine ligand and the jS coordinated nucleobase (con.guration index: OC-6-33).

The structural investigations gave evidence that the sulfur atoms of the nucleobase ligands in 4MeOH and 5 have to be regarded as sp3 and sp2 hybridized, respectively. Thus, the ligand in 4MeOH has to be considered as the deprotonated thiol-amino form of thiocytosine being reprotonated at N1. In complex 5 the 1-MeSCy is coordinated in its thione-amino form. DFT-calculations of the base-paired dinuclear cation in 4 as well as of 4 itself gave proof of the strength of the hydrogen bond (8.5 kcal/mol) and exhibited that cation–anion interactions infuence the conformation of the complex. In vitro cytotoxicity studies of 4 and 5 using nine different human tumor cell lines revealed moderate cytotoxic activity.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis and structures of the novel triple-decker complexes with 9-nickelafluorenyl ring

2009-05-25T20:09:00.006+07:00

Piotr Buchalski a,*, Jolanta Zbrzezna a, Kinga Suwin´ ska b
a Warsaw University of Technology, Faculty of Chemistry, Koszykowa 75, 00-662 Warsaw, Poland
b Institute of Physical Chemistry of the Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland

a r t i c l e i n f o
Article history:
Received 17 July 2008
Accepted 11 October 2008
Available online 18 October 2008
Keywords:
Nickel
Triple-decker
Clusters
Cyclopentadienyl
Metallacyclic compounds

a b s t r a c t
The new triple-decker compounds 2 (C32H33Ni3PF6) and 2a (C42H53Ni3PF6) were synthesised in the reaction of the oxidized 9-nickelfluorenyl sandwich complexes of Nickel (II) 1 (C27H28Ni2PF6) and 1a (C32H38Ni2PF6) in acetone. Decomposition of 1 and 1a followed by the stacking of {CpNi} species on the compounds 1 and 1a, respectively, resulted in the formation of the triple-decker complexes. The compound
2 was characterized by X-ray single crystal analysis. It crystallises from dichloromethane and diethyl ether mixture in the orthorhombic crystal system and the Pna21 space group.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis, characterization and catalytic study of a novel iron(III)-tridentate Schiff base complex in sulfide oxidation by UHP

2009-05-25T20:09:00.005+07:00

Mojtaba Bagherzadeh *, Mojtaba Amini
Chemistry Department, Sharif University of Technology, Azadi Avenue, P.O. Box 11155-3615, Tehran, Iran

a r t i c l e i n f o
Article history:
Received 26 July 2008
Accepted 26 October 2008
Available online 5 November 2008
Keywords:
Sulfoxide
Iron complex
Schiff base
Catalytic oxidation
UHP

a b s t r a c t
An hydrazone Schiff base-iron(III) complex using salicylidene benzoyl hydrazine (L) as ligand has been synthesized and characterized by elemental analyses, IR, 1H and 13C NMR and UV–Vis spectroscopy. Oxidation of sulfides to sulfoxides in one-step was conducted by this complex catalyst using urea hydrogen
peroxide (UHP) in mixture of CH2Cl2/CH3OH (1:1) under air at room temperature. The effect of the reaction conditions on the oxidation of methylphenylsul.de was studied by varying the amount of the catalyst, reaction temperature, reaction time and the amount of UHP. The results showed that using this system in the oxidation of sulfides, sulfoxides were obtained as the main products, together with variable amounts of sulfones (69%), depending on the nature of the substrate.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis, characterization and photostability of several soluble tetra(quinolin-8-yloxy)metallophthalocyanines

2009-05-25T20:09:00.004+07:00

Fangdi Cong a,b, Dongliang Tian b, Junshan Gao a, Wenjuan Duan b,
Chunyu Ma b, Xiguang Du a,b,*
a College of Material Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu, 210016, China
b Faculty of Chemistry, Northeast Normal University, Changchun 130024, China
Received 27 March 2007; received in revised form 4 July 2007; accepted 4 July 2007

Available online 17 July 2007

Abstract
Five tetra(quinolin-8-yloxy)metallophthalocyanines 4a–4e were synthesized from 4-(quinolinyloxy)phthalonitrile in the presence of 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU) as the catalyst, and characterized by MS, 1H NMR, UV–Vis, IR and elemental analysis, which were consistent with the proposed structures. The Q band wavelength of them is related to the metal species in center of Pc rings and follows an order: MnZn≈CuNi≈Co. They all possess excellent solubility in several polar organic solvents, such as chloroform and dichloromethane. But the stability of them, especially that with zinc as coordinated center, is very poor in solutions.
_ 2007 Elsevier B.V. All rights reserved.
Keywords: Phthalocyanine; Synthesis; Characterization; Solubility; Photostability

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Synthesis and structural investigation of vanadocene(IV) complexes of non-linear pseudohalides

2009-05-25T20:06:00.002+07:00

Jan Honzíc¡ek a, Jaromír Vinklárek a,*, Ivana Císar¡ová b, Milan Erben a
a The Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, nám. C¡ s. legií 565, 532 10 Pardubice, Czech Republic
b The Department of Inorganic Chemistry, Charles University, Hlavova 2030, 128 40 Prague 2, Czech Republic

a r t i c l e i n f o
Article history:
Received 10 October 2007
Received in revised form 25 February 2008
Accepted 5 March 2008
Available online 18 March 2008
Keywords:
Bent metallocenes
Pseudohalide complexes
EPR spectroscopy
X-ray crystallography

a b s t r a c t
Two series of vanadocene complexes of the type Cp’2VX2 (Cp’ = ή5-C5H5, ή 5-C5H4Me; X = dicyanamide, tricyanomethanide, dicyanonitrosomethanide) were prepared by the reaction of appropriate vanadocene dichloride complex with alkali salt of non-linear pseudohalide. The bonding mode of pseudohalide ligands was determined by spectroscopic measurements and X-ray diffraction analyses.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis and structural characterization of mixed-ligand silver(I) complexes containing diphosphazanes and bidentate N-donor ligands

2009-05-25T20:05:00.001+07:00

Heera Krishna, Setharampattu S. Krishnamurthy *,1, Munirathinam Nethaji
Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India

a r t i c l e i n f o
Article history:
Received 31 October 2007
Accepted 27 February 2008
Available online 18 March 2008
Keywords:
Phosphorus(III) ligands
N-donor ligands
Silver(I) complexes
NMR spectroscopy
X-ray crystallography

a b s t r a c t
The reactions of a self-assembled silver(I) coordination polymer, [Ag2{l-PriN(PPh2)2}(l-NO3)2]n (1) with various bidentate N-donor ligands such as DABCO, 2,2’-bipyridyl and 1,1’-phenanthroline yield 1-D helices or p–p stacked polymers, depending on the chelate vector of the N-donor ligand. The molecular
structures of the resultant complexes, [Ag2{l-PriN(PPh2)2}(DABCO)(NO3)2]n (2), [Ag2{l-PriN(PPh2)2}- (2,2’-bipy)2(NO3)2] (3) and [Ag2{l-PriN(PPh2)2}(1,1’-phen)2](NO3)2 (4) have been confirmed by singlecrystal X-ray diffraction. Complex 2 exists as an infinite helical polymer because of the exo-bidentate
nature of DABCO. Complex 3 assumes a 2D grid motif as a result of intermolecular p–p stacking among adjacent bipyridine moieties. The phenanthroline complex 4 exhibits strong inter- and intramolecular p–p stacking interactions.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis and structural characterization of a mixed-ligand diiron(II) complex formed by a linked bitopic tris(pyrazolyl)methane ligand: {HC(3,5-Me2pz

2009-05-25T20:03:00.001+07:00

Daniel L. Reger *, Christine A. Little, Radu F. Semeniuc, Mark D. Smith
Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA

a r t i c l e i n f o
Article history:
Received 26 November 2007
Received in revised form 27 March 2008
Accepted 27 March 2008
Available online 7 April 2008
Keywords:
Crystal structure
Tris(pyrazolyl)methane ligands
Low-spin
Iron(II)

a b s t r a c t
The structure of {HC(3,5-Me2pz)3Fe[l-p-C6H4(CH2OCH2C(pz)3)2]Fe(3,5-Me2pz)3CH}(BF4)4 (pz = pyrazolylring) contains two octahedral iron(II) centers linked by a semirigid, bitopic tris(pyrazolyl)methane ligand.The solid-state structure shows the two heteroleptic-bonded iron(II) centers are low-spin at 200 K and situated in a trans orientation with respect to the central linking arene ring.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis and spectroscopic and electrochemical properties of new ligand 1,3-bis(40-methyl-2,20-bipyridin-4-yl)propan-2-one and its ruthenium(II) complexes

2009-05-25T20:01:00.001+07:00

Zhao-Yong Bian a,b,*, Masaoki Furue b
a Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China
b Department of Environmental Systems Engineering, Kochi University of Technology, Tosayamada, Kochi 782-8502, Japan

a r t i c l e i n f o
Article history:
Received 2 September 2008
Accepted 22 October 2008
Available online 29 October 2008
Keywords:
Mono- and dinuclear Ru(II) complexes
Carbonyl group
NMR
Spectroscopic properties
Electrochemistry

a b s t r a c t
A new bridging ligand, 1,3-bis(40-methyl-2,20-bipyridin-4-yl)propan-2-one (L) and its mono- and dinuclear Ru(II) complexes have been synthesized and characterized. The carbonyl group in L keeps its character and does not affect the Ru(II) moieties. In addition, the two Ru(II) terminuses of the dinuclear complex have no interaction through the bridging linkage.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis and solvent dependency study of a novel iron complex with mono-cyanide and mono-carbonyl coordination

2009-05-25T19:57:00.001+07:00

J. Jiang a,*, A. Raytman a, W. Lob, A.M. Etra a, J. Chouake a
a Department of Chemistry, Yeshiva University, New York, NY 10033, United States
b Department of Chemistry, Boston College, Chestnut Hill, MA 02467, United States

a r t i c l e i n f o
Article history:
Received 19 November 2007
Received in revised form 13 March 2008
Accepted 17 March 2008
Available online 23 March 2008
Keywords:
Crystal structure
Iron complex
Cyanide
Carbonyl
IR
Hydrogen bond
Solvent dependency

a b s t r a c t
A novel iron complex [(1,5,8,12-tetraazadodecane)-cyano-iron carbonyl] (1), in which the iron center is coordinated with one cyanide (CN) and one carbonyl (CO), was synthesized. 1’s X-ray crystallographic structure was determined. The structure shows that cyanide and carbonyl are in the cis-isomeric position.
Further infrared study of 1 in a DMF/H2O system has shown that the both CN and CO stretching frequencies are very sensitive to the hydrogen bonding ability of the solvent system.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis and electronic properties of double pincer-type cyclometalated iridium complexes

2009-05-25T19:50:00.001+07:00

Daehyuk Choi a,c, Taehyung Kim b, Samala Malla Reddy a, Jahyo Kang a,*
a Department of Chemistry, Sogang University, Mapoku, Seoul 121-742, Republic of Korea
b Doosan Electromaterials OLED Team, Sungbokdong, Yonginsi, Gyeonggido 449-795, Republic of Korea
c LUDIS Electronic Material Development Team, Baekhyundong, Bundanggu, Sungnamsi, Gyeonggido 463-420, Republic of Korea

a r t i c l e i n f o
Article history:
Received 2 October 2008
Accepted 30 October 2008
Available online 7 November 2008
Keywords:
Double pincer
Spiro Ir complex
Iridium complex
Ancillary electron-carrier
Bis(imidazole)ligand

a b s t r a c t
Double pincer-type cyclometalated iridium complexes were prepared based upon a few assumptions and
their photophysical properties were examined.
Crown Copyright _ 2008 Published by Elsevier B.V. All rights reserved.

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Synthesis and electrochemical studies of octahedral nickel b-diketonate complexes

2009-05-25T19:46:00.003+07:00

Phimphaka Harding a,*, David J. Harding a,*, Wasinee Phonsri b, Saowanit Saithong b, Hirihattaya Phetmung c
a Molecular Technology Unit Cell, Department of Chemistry, Walailak University, Thasala, Nakhon Si Thammarat 80161, Thailand
b Department of Chemistry, Faculty of Science, Prince of Songkhla University, Hat Yai, Songkhla 90112, Thailand
c Department of Chemistry, Faculty of Science, Taksin University, Songkhla 90000, Thailand

a r t i c l e i n f o
Article history:
Received 29 November 2007
Received in revised form 28 February 2008
Accepted 5 March 2008
Available online 18 March 2008
Keywords:
Ni(II) and Ni(III)
b-Diketonates
Cyclic voltammetry
Crystal structure
Octahedral

a b s t r a c t
The reaction of [Ni(tmhd)2] and [Ni(dbm)2] with N-donor chelating ligands in dichloromethane and acetone, respectively, yields the complexes [Ni(tmhd)2(L–L)] (L–L = 2,2’-bpy 1, phen 2 and dmae 3) and [Ni(dbm)2(L–L)] (L–L = 2,2’-bpy 4, phen 5, dmae 6). UV–Vis spectroscopy shows very strong bands in the UV region consistent with ligand centred π→π* transitions. The electrochemical studies of 1–6 reveal oxidation to Ni(III). The [Ni(tmhd)2(L–L)] 1–3 are more easily oxidized by ca. 300 mV and are quasireversible whereas for the [Ni(dbm)2(L–L)] series only complex 6 shows signi.cant reversibility. X-ray crystallographic studies have been conducted in the case of [Ni(dbm)2(phen)] 5 and [Ni(dbm)2(dmae)] 6. The structures both show that the nickel metal centre is octahedral with an O4N2 coordination environment. In the structures the b-diketonate ligands exhibit a cis-arrangement, with the metal displaced out of the planar chelate ring.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis and crystal structure of the singly tucked-in derivative of bis(phenyltetramethylcyclopentadienyl)titanium

2009-05-25T19:45:00.002+07:00

Jir¡í Pinkas a, Ivana Císar¡ová b, Ana Conde c, Rosa Fandos c, Michal Horác¡ek a, Jir¡í Kubišta a, Karel Mach a,*
a J. Heyrovsky´ Institute of Physical Chemistry, v.v.i., Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23 Prague 8, Czech Republic
b Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 128 40 Prague 2, Czech Republic
c Departamento de Química Inorgánica, Orgánica y Bioquímica, Facultad de Ciencias del Medio Ambiente, Universidad de Castilla-La Mancha, Avd. Carlos III, s/n, 45071 Toledo, Spain

a r t i c l e i n f o
Article history:
Received 22 September 2008
Accepted 23 October 2008
Available online 5 November 2008
Keywords:
Titanium
Titanocene
Tucked-in
Phenyltetramethylcyclopentadienyl ligand
Thermolysis
X-ray crystallography
NMR spectra
EPR spectra

a b s t r a c t
Thermolysis of [TiMe2(ή5-C5Me4Ph)2] (4) at 145 _C for 5 h afforded the singly tucked-in paramagnetic titanocene [Ti(III)(ή5-C5Me4Ph){ή5:g1-C5Me3Ph(CH2)}] (9). In distinction to the singly tucked-in permethyltitanocene [Ti(III)(ή5-C5Me5){ή5:ή1-C5Me4(CH2)}] (1) which was found crystallographically disordered [J.M. Fischer, W.E. Piers, V.G. Young, Jr., Organometallics 15 (1996) 2410] the single crystal X-ray diffraction analysis of 9 afforded molecular parameters with nearly by one order better precision as measured by esd-values.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis and characterization of new ruthenium(II) complexes containing coupled di(2-pyridyl) and 1,3-dithiole units

2009-05-25T19:43:00.002+07:00

Ya Chen a, Wei Liu a, Bin Liu b, Xin-Hui Zhou a, Zhi-Gang Zou b, Jing-Lin Zuo a,*, Xiao-Zeng You a
a Coordination Chemistry Institute and the State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering,
Nanjing University, Nanjing 210093, PR China
b National Laboratory of Solid State Microstructure, Nanjing University, Nanjing 210093, PR China

a r t i c l e i n f o
Article history:
Received 21 October 2007
Received in revised form 21 February 2008
Accepted 12 March 2008
Available online 16 March 2008
Keywords:
Ruthenium(II) complexes
1,3-Dithiole
Crystal structures
Dye sensitizer
Solar cells

a b s t r a c t
Two new ruthenium (II) complexes containing coupled di(2-pyridyl) and 1,3-dithiole units, cis-[Ru(Medpydt)2(NCS)2] (2, Medpydt = dimethyl 2-(di(2-pyridyl)methylene)-1,3-dithiole-4,5-dicarboxylate) and cis-[Ru(H2dpydt)2(NCS)2] (3, H2dpydt = 2-(di(2-pyridyl)methylene)-1,3-dithiole-4,5-dicarboxylate), have
been synthesized and characterized. The structure of complex 2 has been determined by X-ray crystallography. There exist intermolecular H-bonding interactions between carbomethoxy groups on neighboring pyridine rings giving rise to 2D H-bonded arrays. The metal-to-ligand charge-transfer (MLCT) absorptions were observed around 480 nm. Redox properties of ruthenium complexes have been investigated by cyclic voltammetry. Solar cells involving thin .lms of anatase TiO2 impregnated with cis-[Ru(H2d-pydt)2(NCS)2] were prepared, and the photovoltaic performance was preliminarily investigated.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis and characterization of binuclear mercury(II) complexes of phosphorus ylides, X-ray analysis and multinuclear NMR measurements

2009-05-25T19:37:00.000+07:00

Seyyed Javad Sabounchei a,*, Hassan Nemattalab a, Sadegh Salehzadeh a, Sima Khani a, Mehdi Bayat a,
Harry Adams b, Michael D. Ward b
a Faculty of Chemistry, Bu-Ali Sina University, Hamedan 65174, Iran
b Department of Chemistry, University of Shef.eld, Shef.eld S3 7HF, UK

a r t i c l e i n f o
Article history:
Received 25 December 2007
Received in revised form 26 February 2008
Accepted 5 March 2008
Available online 18 March 2008
Keywords:
Phosphorus ylide
Mercury(II) halide
Binuclear complex
C-Coordination

a b s t r a c t
The reactions of phosphorus ylide (p-tolyl)3PCHC(O)CH3 (Y1) with HgX2 (X = Cl and Br) and (p-tolyl)3- PCHC(O)C6H4NO2 (Y2) with HgX2 (X = Cl, Br and I) in equimolar ratios using methanol as a solvent are reported. These reactions led to binuclear complexes. C-Coordination of ylides and trans-like structure of complexes [(Y1).HgBr2]2 and [(Y2).HgBr2]2.2DMSO are demonstrated by single crystal X-ray analyses. The IR, 1H, 13C and 31P NMR data for the other synthesized compounds are similar to the latter complexes, indicating similar structures. Elemental analyses indicate a 1:1 stoichiometry between the ylide
and Hg(II) halide in all the products. The ab initio studies indicated that for all dimeric compounds, the observed trans-like structures are 7–10 kcal/mol more stable than the alternative possible cis-like isomers. Although the calculated bond lengths are slightly longer than the measured ones, the similarity of calculated and measured bond angles re.ects the similar geometrical structures for these compounds in both the solid state and the gas phase.
_ 2008 Elsevier B.V. All rights reserved.
http://www.ziddu.com/download/5206208/andcharacterizationofbinuclearmercuryIIcomplexes.pdf.html

Hydrothermal synthesis, structure and rare ferromagnetic property of a 3-D Nd(III) metal–organic framework based on mixed pyridine-2,5-dicarboxylic acid

2009-05-25T11:13:00.032+07:00

Dao-Jun Zhang, Tian-You Song, Li Wang, Jing Shi, Jia-Ning Xu, Ying Wang, Kui-Rong Ma,
Wei-Rong Yin, Li-Rong Zhang *, Yong Fan *
State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, PR China

a r t i c l e i n f o
Article history:
Received 8 October 2007
Received in revised form 20 March 2008
Accepted 20 March 2008
Available online 31 March 2008
Keywords:
Metal–organic framework
Magnetic
Hydrothermal synthesis
Mixed ligands

a b s t r a c t
A novel 3-D metal–organic framework Nd(2,5-pydc)(nic)(H2O) (1, 2,5-pydc = pyridine-2,5-dicarboxylic acid, nic = nicotinic acid) has been hydrothermally synthesized and characterized by elemental analyses, IR, and X-ray single-crystal diffraction. Compound 1 is the first MOF based on mixed 2,5-pydc/nic ligands. The title compound displays an interseting 3-D (6,3)-connected network with the topology of (4.62)2(42 _ 610 _ 83). Magnetic susceptibility measurements show that compound presents a rare ferromagnetic interaction between two adjacent Nd(III) ions.
_ 2008 Elsevier B.V. All rights reserved.

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In vitro and in vivo studies of the dermally absorbed Cu(II) complexes of N5O2 donor ligands – Potential anti-inflammatory drugs

2009-05-25T11:13:00.031+07:00

Sebusi Odisitse, Graham E. Jackson *
Department of Chemistry, University of Cape Town, Private Bag Rondebosch, 7701, Cape Town, South Africa

a r t i c l e i n f o
Article history:
Received 30 October 2007
Received in revised form 15 February 2008
Accepted 11 March 2008
Available online 24 March 2008
Keywords:
Rheumatoid arthritis
Copper(II)
Speciation
Potentiometry
Spectroscopy
Bio-modelling
Bio-distribution

a b s t r a c t
Copper complexes of N,N0-di(aminoethylene)-2,6-pyridinedicarbonylamine and bis-(N,N-dimethylethyl)- 2,6-pyridinedicarboxamide have been studied by glass electrode potentiometry, NMR, UV and IR spectroscopy as potential anti-inflammatory agents for the alleviation of inflammation associated with rheumatoid arthritis. The protonation and formation constants with Cu(II), Zn(II) and Ca(II), determined at 25 _C and an ionic strength of 0.15 mol dm3 were used to calculate the copper plasma mobilizing index of the ligands. Spectroscopic studies suggested that metal ion complexation promotes deprotonation and coordination of the amide nitrogens resulting in overall tetragonal distorted copper complexes. Bio-distribution and dermal absorption studies showed the complexes to have relatively long biological half-lives with 50% of the injected dose remaining in the body 24 h after administration.
_ 2008 Elsevier B.V. All rights reserved.

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Luminescence and photoreactivity of Ag(8-quinolinol)(8-quinolinolate)

2009-05-25T11:13:00.030+07:00

Horst Kunkely, Arnd Vogler *

Institut für Anorganische Chemie, Universität Regensburg, D-93040 Regensburg, Germany

a r t i c l e i n f o

Article history:

Received 9 January 2008

Received in revised form 12 March 2008

Accepted 17 March 2008

Available online 24 March 2008

Keywords:

Luminescence

Photochemistry

Silver

Quinolinolate

a b s t r a c t

The complex Ag(8-quinolinol)(8-quinolinolate) shows an IL fluorescence while an IL phosphorescence does not appear. The IL triplet is deactivated to a reactive LMCT state. A subsequent photoredox reaction leads to generation of elemental silver.

_ 2008 Elsevier B.V. All rights reserved.

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Mercury(II) acetate/thiocyanate coordination polymers with n-donor ligands, spectroscopic, thermal and structural studies

2009-05-25T11:13:00.029+07:00

Ghodrat Mahmoudi a, Ali Morsali a,*, Matthias Zeller b
a Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, P.O. Box 14155-4838, Tehran, Islamic Republic of Iran
b Department of Chemistry, Youngstown State University, One University Plaza, P.O. Box 44555-3663, Youngstown, OH, USA

a r t i c l e i n f o
Article history:
Received 29 October 2007
Received in revised form 16 March 2008
Accepted 18 March 2008
Available online 25 March 2008
Keywords:
Mercury(II)
Coordination polymer
1,2-Bis(4-pyridyl)ethane
1,4-Bis(4-pyridyl)-2,3-diaza-1,3- butadiene
1,4-Bis(3-pyridyl)-2,3-diaza-1,3-butadiene

a b s t r a c t
Three new mercury(II) coordination polymers, [Hg2(l-bpa)(l-SCN)2(l-CH3COO)2]n (1), [Hg2(l-4-bpdb)1.5-(l-CH3COO)(l1,1- SCN)(l1,3-SCN)(SCN)]n _ CH3CN (2) and [Hg(l-3-bpdb)(CH3COO)2]n (3) {(bpa = 1,2-bis(4-
pyridyl)ethane, 4-bpdb) = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene and 3-bpdb = 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene, have been synthesized and characterized by CHN elemental analysis and IR spectroscopy. The single crystal X-ray data show the compound 1 is two-dimensional coordination polymer
as a result of simultaneously bridging 1,2-bis(4-pyridyl)ethane, acetate and thiocyanate ligands. The single-crystal X-ray data of the compound 2 show that the complex to be a two-dimensional polymer, one of Hg atoms has four-coordinate and one of them has seven-coordinate. Three SCN_ anions show
three different coordination modes with terminal, l1,1-bridge and l1,3-bridge fashions. The structural studies of compound 3 show the structure may be considered a one-dimensional coordination polymer of mercury(II) consisting of linear chains formed by a bridging 3-bpdb ligand. The thermal stabilities of
these compounds were studied by thermal gravimetric (TG) and differential thermal analyses (DTA).
_ 2008 Elsevier B.V. All rights reserved.

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Mixed-ligand silver(I) complexes containing bis[2-(diphenylphosphino)phenyl]ether and pyridyl ligands

2009-05-25T11:13:00.028+07:00

Maravanji S. Balakrishna a,*, Ramalingam Venkateswaran a, Shaikh M. Mobin b
a Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400 076, India
b National Single Crystal X-ray Di.raction Facility, Indian Institute of Technology Bombay, Mumbai 400 076, India

Received 13 December 2007; received in revised form 8 February 2008; accepted 19 February 2008
Available online 26 February 2008

Abstract
The reaction of [Ag2(j2-P,P0-DPEphos)2(l-OTf)2] (1) (DPEphos = bis(2-(diphenylphosphino)phenyl]ether) with 1,10-phenanthroline (phen) and 4,40-bipyridine in equimolar ratios afford, respectively, the mononuclear complex [Ag(j2-P,P0-DPEphos)(phen)][OTf] (2) and the coordination polymer [Ag(j2-P,P0-DPEphos)(l-4,40-bpy)]n[OTf]n (3). In complex 3, the silver atoms are bridged by 4,40-bipyridine units to form a zigzag metallopolymer.
_ 2008 Elsevier B.V. All rights reserved.
Keywords: Mixed-ligand silver complexes; DPEphos; Polypyridyl; Zigzag polymer; p-Stacking; Chelate mode of coordination

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Nickel(II) complexes bearing pyrazolylimine ligands: Synthesis, characterization, and catalytic properties for ethylene oligomerization

2009-05-25T11:13:00.027+07:00

Yuan-yuan Wang, Shang-an Lin, Fang-ming Zhu *, Hai-yang Gao, Qing Wu
Institute of Polymer Science, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China

a r t i c l e i n f o
Article history:
Received 30 October 2007
Accepted 14 March 2008
Available online 20 March 2008
Keywords:
Pyrazolylimine nickel complexes
X-ray single-crystal analyses
Ethylene oligomerization
Methylaluminoxane

a b s t r a c t
Four phenyl-substituted pyrazolylimine ligands 2-(C3HN2Me2-3,5)(C(Ph)=N(4-R2C6H2(R1)2-2,6)) (L1:R1 = iPr, R2 = H; L2: R1 = H,R2 = NO2; L3: R1 = R2 = H; L4: R1 = H,R2 = OCH3) were synthesized. The influences of steric bulk and electronic effect of pyrazolylimine ligands on the structures of their corresponding nickel complexes were investigated. Ligands with more bulky and electron withdrawing substituents on N-phenyl ring produced four-coordinate nickel complexes (2-(C3HN2Me2-3,5))(C(Ph)=(4-R2C6H2(R1)2-2,6)NiBr2
(1, R1 = iPr, R2 = H; 2, R1 = H, R2 = NO2)), whereas the ligands with less bulky and electron donating substituents on N-phenyl ring formed bis-pyrazolylimine dinickel tetrahalides (bis-2-(C3HN2Me2-3,5)) (C(Ph)=N(4-R2C6H2 (R1)2-2,6)Ni2Br4 (3, R1 = R2 = H; 4, R1 = H, R2 = OCH3)) and six-coordinate nickel dihalides (bis-2-(C3HN2Me2-3,5))(C(Ph)=N(4-R2C6H2(R1)2-2,6) NiBr2 (5, R1 = R2 = H; 6, R1 = H, R2 = OCH3)).The solid-state structures of complexes 1, 4 and 5 have been confirmed by X-ray single-crystal analyses. Activated by methylaluminoxane (MAO), complexes 1, 2, 5 and 6 showed moderate to high activity for ethylene oligomerization, and complex 5 revealed the highest activity up to 8.96 _ 105 g oligomer/(mol Ni _ h).The proportions of resultant oligomers were mainly C4–C8 and a little C10–C14 determined by gas chromatography/ mass spectrometry.
_ 2008 Elsevier B.V. All rights reserved.

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Novel luminescent europium(III) complexes covalently bonded to bis(phosphino)amine oxide functionalized MCM-41

2009-05-25T11:13:00.026+07:00

Qian-Yong Cao *, Yan-Hui Chen, Jiang-Hua Liu, Xi-Cun Gao *
Department of Chemistry, Nanchang University, Nanchang 330031, China

a r t i c l e i n f o
Article history:
Received 21 July 2008
Accepted 25 October 2008
Available online 5 November 2008
Keywords:
MCM-41
Luminescence hybrid materials
Covalently bonded
Europium complex

a b s t r a c t
A novel organo-functionalized mesoporous MCM-41 type of hybrid materials MCM–Si–DPBB was synthesized by co-condensation of bidentate Si(OR)3 substituted N,N-2-diphenyloxyphosphine-4-bromomethyl- benzenamine (Si–DPBB) and tetraethoxysilane (TEOS) in the presence of the cetyltrimethylammonium bromide (CTAB) surfactant as template. Its ternary europium complex covalently bonded to the silica-based network MCM–Si–DPBB–Eu was also prepared by introduction the Eu(DBM)3(H2O)2 into the hybrid materials. The hybrid material MCM–Si–DPBB–Eu has strong luminescence, and when excited by the ligands absorption wavelength (386 nm), it displays the emission of the Eu3+ 5D0-7FJ (J = 0, 1, 2, 3 and 4) transition lines due to the ef.cient energy transfer from the ligands to Eu3+.
_ 2008 Elsevier B.V. All rights reserved.

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One-dimensional channels constructed from hydrogen bonding networks among 4,40-bipyridine units and water molecules available for accommodation

2009-05-25T11:13:00.025+07:00

Hidekazu Kobayashi a, Kazuya Ikarashi a, Kazuyoshi Uematsu a, Kenji Toda a,
Hirokazu Okawa b, Zhu Taoyun a, Mineo Sato a,*
a Department of Chemistry and Chemical Engineering, Faculty of Engineering, Niigata University, Ikarashi 2-no-cho, Niigata 950-2181, Japan
b Department of Earth Science and Technology, Faculty of Engineering and Resource Science, Akita University, Tegata Gakuen-machi,
Akita 010-8502, Japan

Received 26 April 2007; received in revised form 19 July 2007; accepted 25 July 2007
Available online 23 August 2007

Abstract
A hybrid coordination complex, [(H5O2)(H2bpy)(bpy)4][NaMo8O26] Æ 2H2O (bpy = 4,4-bipyridine), was synthesized via hydrothermal reactions at 150 _C. The structure consists of two moieties; one is an infinite chain of b-[Mo8O26] clusters, each of which is inter-linked up by a sodium ion, and the other a two-dimensional network constructed from doubly protonated bpy ions and its neutral molecules,
which are linked with water molecules by hydrogen bonds. The stacking of the networks provides one-dimensional tunnels suitable
for Na–b-[Mo8O26] chains.
_ 2007 Published by Elsevier B.V.
Keywords: Polyoxometalate; Octamolybdate; Inorganic–organic hybrid material; Hydrothermal synthesis; Crystal engineering

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Optical and EPR spectra of the thionitrosyl complex [Cr(OH2)5(NS)]2+

2009-05-25T11:13:00.024+07:00

Johannes W. Dethlefsen, Anders Døssing *
Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark

Received 3 October 2007; received in revised form 4 February 2008; accepted 8 February 2008
Available online 15 February 2008

Abstract
The green thionitrosyl complex [Cr(OH2)5(NS)]2+ was isolated in solution by the hydrolysis of [Cr(NCCH3)5(NS)]2+. The optical absorption spectra of both compounds are dominated by a band with vibrational progression around 600 nm assigned as a {dyz,zx,π*(NS)} →{ π *(NS),dyz,zx}* transition. The optical data indicate that the NS ligand is a weaker p-acceptor than the NO ligand.
The EPR parameters of [Cr(OH2)5(NS)]2+ were determined: giso, gll and g┴: 1.96515, 1.92686(5) and 1.986860(8); Aiso(53Cr), All(53Cr) and A┴ (53Cr): 25.3 _ 10-4, 38x10-4 and 18.5 x 10-4 cm-1; Aiso(14N), All(14N) and A┴(14N): 6.5 x 10-4, 2.81 _ 10_4 and 8.346(12) x 10-4 cm-1.
_ 2008 Elsevier B.V. All rights reserved.
Keywords: Thionitrosyl; Chromium; Hydrolysis; EPR spectra; UV–Vis

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Oxotungsten(VI) complexes with amino(phenolate)alcoholate ligand

2009-05-25T11:13:00.023+07:00

Oula Wichmann a, Ari Lehtonen b,*
a Laboratory of Inorganic Chemistry, Department of Chemistry, University of Jyväskylä, FIN-40351 Jyväskylä, Finland
b Laboratory of Materials Chemistry and Chemical Analysis, Department of Chemistry, University of Turku, FIN-20014, Turku, Finland

a r t i c l e i n f o
Article history:
Received 11 September 2008
Accepted 23 October 2008
Available online 30 October 2008
Keywords:
Alkoxide complexes
Oxo complexes
Phenolate ligands
Tungsten

a b s t r a c t
The reaction between tungsten(VI) complex [W(eg)3] (eg = 1,2-ethanediolato dianion) and a phenolic ligand precursor 2,4-di-tert-butyl-6-(((2-hydroxyethyl)(methyl)amino)methyl)phenol (H2L) affords a monomeric oxotungsten complex [WO(eg)(L)]. This complex reacts further with Me3SiCl, which leads to the displacement of ethanediolato ligand from the complex unit and formation of cis- and trans-isomers of corresponding dichloro complex [WOCl2(L)]. Identical dichloro complexes were also prepared by the reaction between H2L and WOCl4. Molecular structure of [WO(eg)(L)] was veri.ed by X-ray crystallography.
_ 2008 Elsevier B.V. All rights reserved.

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Silver(I) cis-diphenylphosphinoethylene complexes: Spectroscopic and structural characterization

2009-05-25T11:13:00.021+07:00

Claudio Pettinari a,*, Alessandro Marinelli a, Adriano Pizzabiocca a, Effendy b,c,
Brian W. Skelton c, Allan H. White c
a Dipartimento di Scienze Chimiche, Università di Camerino, via S. Agostino 1, 62032 Camerino (MC), Italy
b Chemistry M313, SBBCS, University of Western Australia, Crawley, WA 6009, Australia
c Jurusan Pendidikan Kimia, FMIPA Universitas Negeri Malang, Jalan Surabayah, Malang 65145, Indonesia

a r t i c l e i n f o
Article history:
Received 25 September 2008
Accepted 6 November 2008
Available online 13 November 2008
Keywords:
Ag(I) complexes
Diphosphine ligands
X-ray
Spectroscopy

a b s t r a c t
Adducts of the diphosphine cis-Ph2P(CH=CH)PPh2 (L) with AgX (X = NO3, BF4, ClO4 or CF3SO3) have been synthesized and characterized both in solution (1H, 31P NMR) and in the solid state (IR, single crystal Xray structure analysis). The topologies of the structures in the solid state were found to depend on the
nature of the counter-ion X. The adduct AgNO3:L (2:1)2 is tetranuclear, derivative of the chair form, the bidentate ligands bridging peripheral silver centers, the nitrates being coordinated through two oxygen atoms, the first O,O’-bridging, the second bridging bidentate.
_ 2008 Elsevier B.V. All rights reserved.

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Synthesis and characterization of a chiral Schiff base containing α-D-altropyranoside unit and its zinc(II) complex*

2009-05-25T11:13:00.020+07:00

Pei Liu, Ji-cheng Shi *, Qingsong Tong, Yangfang Feng, Hua Huang, Li Jia
College of Chemistry and Materials Science, Fujian Normal University, Fuzhou 350007, China

a r t i c l e i n f o
Article history:
Received 25 January 2008
Received in revised form 11 March 2008
Accepted 20 March 2008
Available online 7 April 2008
Keywords:
Schiff base
Zinc(II) complex
Carbohydrate
Tetradentate chelate

a b s t r a c t
A novel chiral Schiff base containing α-D-altropyranoside unit, methyl 4,6-O-benzylidene-3-deoxy-3-(2- salicylideneaminoethylamino)-a-D-altropyranoside (3, Me-Alt-NNOH), has been prepared. Treatment of zinc chloride with 3 in the presence of triethylamine afforded a .ve-coordinated zinc(II) complex [Zn(Me-Alt-NNO)Cl] (4). Both 3 and 4 have been characterized by infrared, 1H NMR, 13C NMR, MS, and elemental analysis. The crystal structure of 4 has been determined by X-ray diffraction. Crystal structure analysis shows that the complex 4 exits a distorted triangular bipyramid geometry and the Schiff base motif acts as a uninegatively charged tetradentate chelating agent. The methoxy and amino groups cischelate to the zinc atom and the pyrano-ring is in an ideal 4C1 chair conformation.
_ 2008 Elsevier B.V. All rights reserved.

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Hydrogen exchange of rhenium(VII) heptahydridobis(triphenylphosphine) with water, aniline, methanol, and itself

2009-05-25T11:13:00.019+07:00

Janith A. Wazio a, Veronica Jimenez b, Santosh Soparawalla a, Sam John a, Gregory A. Moehring b,*
a Division of Science, Governors State University, University Park, IL 60466, United States
b Department of Chemistry, Texas A&M University – Kingsville, Kingsville, TX 78363, United States

a r t i c l e i n f o
Article history:
Received 5 February 2008
Received in revised form 13 March 2008
Accepted 13 March 2008
Available online 18 March 2008
Keywords:
Rhenium
Hydride
Polyhydride
Hydrogen exchange
NMR

a b s t r a c t
The hydride ligands of ReH7(PPh3)2 undergo fast hydrogen exchange with water at room temperature while exchanging with the hydrogen atoms of aromatic solvent molecules at a slower rate. The amount of time required for isotopomer peaks to appear in the 1H NMR hydride resonance of ReH7(PPh3)2 was used to distinguish fast hydrogen exchange from slow hydrogen exchange. The room temperature 1H NMR T1 values of adventitious water resonances were used to distinguish two rhenium heptahydride compounds that participate in fast hydrogen exchange with water, ReH7(PPh3)2 and ReH7(AsPh3)2, from
one compound that does not participate, ReH7(PCy3)2. Fast hydrogen exchange between ReH7(PPh3)2 and water is greatly slowed or stopped when the compound is dissolved in a solution that contains DMSO. The compound ReH6D(PPh3)2, an isotopomer of ReH7(PPh3)2 that was prepared in situ, exhibited an isotopomer shift in its 31P–{1H} NMR spectrum as well as D–P coupling when measured in the solvent anisole. In a solvent system containing deuteroaniline, nearly all of the hydride ligands were exchanged with deuterium, from aniline, in less than 2 h. Hydrogen exchange between the hydride ligands of ReH7(PPh3)2
and deuteroaniline was found to be reversible upon the addition of normal aniline. The distribution of hydrogen isotopes in the rhenium coordination spheres re.ected the overall composition of the exchangeable hydrogen isotopes present in the bulk sample. In a deuteromethanol-containing solvent system, the exchange of hydride ligands between separate ReH7(PPh3)2 isotopomers was evident. The presumed hydrogen exchange intermediate, [ReH6(H2)(PPh3)2]+, may be responsible for the evident exchange of hydride ligands and may also be important to the thermal loss of dihydrogen from ReH7(PPh3)2.
_ 2008 Elsevier B.V. All rights reserved.

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Excited state properties of dinaphthyl ditelluride

2009-05-25T11:13:00.018+07:00

Horst Kunkely, Arnd Vogler *
Institut für Anorganische Chemie, Universität Regensburg, D-93040 Regensburg, Germany

a r t i c l e i n f o
Article history:
Received 26 October 2007
Accepted 9 January 2008
Available online 9 July 2008
Keywords:
Electronic spectra
Photochemistry
Phosphorescence
Luminescence
Charge transfer
Tellurium

a b s t r a c t
Di-1-naphthyl ditelluride (Te2naphthyl2) is characterized by two low-energy excited states. The corresponding electronic transitions nTe→σ* Te–Te and nTe→π* naphthyl CT give rise to absorptions at kmax = 403 and 311 nm, respectively. In solution nTe→σ* excitation leads to the cleavage of the Te–Te
bond. In contrast to Te2naphthyl2 in the dissolved state the solid compound shows a luminescence (kmax = 576 nm) which originates from nTe→ π * naphthyl CT triplet.
_ 2008 Elsevier B.V. All rights reserved.

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Discrete and 1D coordination polymeric chloro-bridged copper(II) dimers exhibiting ferro- and antiferromagnetic exchange coupling: Magneto-structural

2009-05-25T11:13:00.016+07:00

Sukanta Mandal a, Francesc Lloret b, Rabindranath Mukherjee a,*
a Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
b Departament de Química Inorgànica, Instituto de Ciencia Molecular (ICMOL), Universitat de València, Polígono de la Coma, s/n, 46980-Paterna, València, Spain

a r t i c l e i n f o
Article history:
Received 7 January 2008
Accepted 26 February 2008
Available online 10 March 2008
Keywords:
Copper(II)
Tridentate 2-pyridylalkylamine ligand
m-Xylyl-based ligands with 2-
pyridylalkylamine and pyrazole
Crystal structure
Magnetic properties

a b s t r a c t
The synthesis and characterization of two 1D coordination polymers [Cu2(MHL)Cl2][ClO4]2.CH3CN .THF (2 CH3CN.THF) and [Cu2(MPyPz)Cl2][ClO4]2.CH3CN (3CH3CN), having repetitive {CuII2 (μ-Cl)2} units, of m-xylyl-based ligands with terminal tridentate (2-pyridyl)alkylamine (MHL = a,a0-bis[N-(2-pyridylethyl)-N-(2-pyridylmethyl)amino]-m-xylene) and (2-pyridyl)alkylamine/pyrazole (MPyPz = a,a0-bis[N-(2-pyridylethyl)-N-(pyrazol-1-ylmethyl)amino]-m-xylene) coordination have been accomplished. X-ray crystallographic studies reveal that the copper(II) centers in the recently reported dichloro-bridged discrete CuII2 (μ-Cl)2} complex [{Cu(MeL)Cl}2][ClO4]2 (1) of a tridentate (2-pyridyl)alkylamine ligand [MeL = methyl[2-(2-pyridyl)ethyl](2-pyridylmethyl)amine], 2 CH3CN.THF, and 3CH3CN have distorted square-pyramidal geometry, sharing a base-to-apex edge with parallel basal planes. Variabletemperature susceptibility measurements in the range of 2–300 K reveal antiferromagnetic for 1 [J(singlet–triplet energy gap) = -3.89 cm1] and 2CH3CN.THF (J =1.84 cm1), and ferromagnetic for 3CH3CN (J = +6.27 cm1) coupling. The complexes provide useful information for the magneto-structural correlations.
_ 2008 Elsevier B.V. All rights reserved.

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Platinum(II) and copper(I) 1-(2-diphenylphosphino-1-naphthyl) isoquinoline complexes: Synthesis and phosphorescence at ambient conditions

2009-05-23T11:50:00.001+07:00

Valeri Pawlowski, Horst Kunkely, Arnd Vogler *
Institut für Anorganische Chemie, Universität Regensburg, D-93040 Regensburg, Germany

a r t i c l e i n f o
Article history:
Received 12 February 2008
Received in revised form 19 March 2008
Accepted 20 March 2008
Available online 28 March 2008
Keywords:
Luminescence
Phosphorescence
Platinum(II)
Copper(I)
1-(2-Diphenylphosphino-1-
naphthyl)isoquinoline

a b s t r a c t
The compounds Pt(quinap)(CN)2, CuðquinapÞþ2 and [Cu(quinap)I]2 with quinap = 1-(2-diphenylphosphino-1-naphthyl)isoquinoline were synthesized. Quinap is a bidentate ligand which contains a isoquinoline and an arylphosphine group with CT acceptor properties. Accordingly, the Pt(II) and Cu(I) quinap complexes are characterized by a phosphorescence originating from the lowest-energy MLCT triplets with some IL admixture.
_ 2008 Elsevier B.V. All rights reserved.

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The Using of Immobilized Biosurfactant Into The Allophane for Cd Metal Ion Adsorbent

2009-05-23T11:16:00.005+07:00

By Setyo Nugroho
The Faculty of Chemistry, Sebelas Maret University

The using of immobilized biosurfactant into the allpohane for Cd metal ion adsorbent has been done. Purposes of this research were to know the capability of immobilized biosurfactant to adsorpt the capability of immobilized biosurfactant to adsorpt the Cd metal ion, the optimum condition of Cd metal ion adsorption by immobilized biosurfactant, and its adsorption capability compared to the adsorption capability of allophone. The biosurfactant was produced through biotransformation by P. aeruginosa using tapioca industrial wastewater (Biospapueiera). Meanwhile, the allophone was obtained from Mount Lawu, Central Java.
The research was carried out in the variation of pH, which were pH 2, 4, 6, and the variation of contact time were 0, 5, 10, 20, 30, and 45 minutes. They were used to get the optimum condition in adsorption process. The method used in the adsorption was batch method. The Atomic Adsorption Spectroscopy was used to determine the concentration of Cd metal ion in solution. The concentration of Cd metal ion was adsorpted was determined by differences of the concentration Cd metal ion before and after adsorpted.
The result showed that the immobilized biosurfactant could be used to adsorpt the Cd metal ion, while optimum condition reached at pH 6 and the time contact was 20 minutes with the values of capacity adsorption was 0,0420±0,0009mg/g. The result showed that the capability adsorption of the immobilized biosufactant was smaller than that of allophone. The adsorption capacity of Cd metal ion in model solution by the allophone and the immobilized biosurfactant was 0,0250±0,0003 and 0,0230±0,0049 mg/g, respectively. The adsorption capacity for Cd metal ion in electroplating waste water by the allophone and the immobilized biosurfactant was 0,0386±0,0008 and 0,0345±0,0016 mg/g, respectively.
Keyword : Cd metal ion, immobilization, biosurfactant, immobilized biosurfactant

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Remarkable chiral and luminescent properties of novel Yb(III) and Eu(III) complexes containing BINAPO ligand

2009-05-23T11:16:00.003+07:00

Md. Abdus Subhan a,*, Yasuchika Hasegawa b, Takayoshi Suzuki c, Sumio Kaizaki c, Yanagida Shozo b
a Department of Chemistry, Shah Jalal University of Science and Technology, Sylhet, Bangladesh
b Department of Material and Life Science, Faculty of Engineering, Osaka University, Osaka, Japan
c Department of Chemistry, Faculty of Science, Osaka University, Osaka, Japan

a r t i c l e i n f o
Article history:
Received 2 September 2007
Received in revised form 29 January 2008
Accepted 11 March 2008
Available online 23 March 2008
Keywords:
Circular dichroism
Dissymmetry factors
Red emission
Lanthanide
Chirality

a b s t r a c t
Lanthanide complexes are of great importance for their prospective applications in wide range of science and technology. Chiral lanthanide complexes can constitute stereo-discriminating probes in biological media, owing to the luminescent properties of the rare-earth ions. Sensitized emission with narrow bandwidth, having fast radiation rate and high emission quantum ef.ciency are the main perspective for synthesizing the complexes. Attention has been given on remarkable chirality with high dissymmetry factors (g = Deext/emax) of the complexes. For this purpose, beta-diketonato ligands with chiral BINAPO
(1,10-binapthyl phosphine oxide) ligand were chosen to achieve the goal. The complexes [Ln(TFN)3- (S-BINAPO)](TFN = 4,4,4-tri.uoro-1(2-napthyl)-1,3-butanedione), [Ln(HFT)3(S-BINAPO)] (HFT = 4,4,5,5,6,6,6-
heptafluoro-1-(2-thienyl)-1,3-hexanedione) and [Ln(HFA)3(S-BINAPO)](hfa = hexafluoroacetylacetonate) (where Ln = Yb, Eu) were synthesized. The complex, [Eu(TFN)3(S-BINAPO)] gives strong red emission at 615 nm with narrow emission band (<10 nm) when excited by 465 nm light with quantum efficiency 86%. The dissymmetry factors (g = ∆εext/εmax) corresponding to the 7F1→5D transition at 590 nm is 0.091 for [Eu(TFN)3(S-BINAPO)] and for [Yb(hfa)3(S-BINAPO)](hfa = hexafluoroacetylacetonate) corresponding to the 2F7/2→2F5/2 transitions is 0.12, are among the largest values for both Eu and Yb complexes to date, respectively. The Eu complexes, [Eu(HFT)3(S-BINAPO)] and [Eu(TFN)3(S-BINAPO)] are found to be spontaneously emissive, showing bright red emission, when placed in sunlight or even in the laboratory when light is switched on. _ 2008 Elsevier B.V. All rights reserved.

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A wide family of pyridoxal thiosemicarbazone ferric complexes: Syntheses, structures and magnetic properties

2009-05-11T13:09:00.028+07:00

Sébastien Floquet a,*, M. Carmen Muñoz b, Régis Guillot a, Eric Rivière a, Guillaume Blain a,
José-Antonio Réal c, Marie-Laure Boillot a
a ICMMO, Equipe Chimie Inorganique, UMR CNRS 8182, Univ. Paris-Sud, 91400 Orsay, France
b Departament de Fisica Aplicada, Universitat Politécnica de València, Cami de Vera s/n, 46022 València, Spain
c Universitat Valencia, Institut de Ciència Molecular/Departament de Quimica Inorganica, Edi.ci de Instituts de Paterna, Apartat de Correus 22085, València 46071, Spain

a b s t r a c t
This study reports the syntheses and the characterization of 12 ferric complexes of pyridoxal thiosemicarbazone. The richness of the coordination chemistry of this ligand is highlighted by the modulation of its charge from neutral H2L to anionic L2_, thus leading to a wide family of ferric compounds with charge varying from +3 to _1. The structures of complexes [Fe(HL)2]ClO4 _ 2H2O and [Fe(HL)L] _ 4.5H2O were solved and discussed with a particular attention brought to the intermolecular interactions occurring between the complexes. The investigation of magnetic properties of these compounds revealed that two of them are in the HS state at any temperature, whereas the others are in the LS state. These results are discussed in relation to the modulation of the electronic properties of the ligand.
_ 2008 Elsevier B.V. All rights reserved.

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Complexation thermodynamics and the formation of the binary and the ternary complexes of tetravalent plutonium with carboxylate and aminocarboxylate l

2009-05-11T13:09:00.027+07:00

P. Thakur, P.N. Pathak 1, G.R. Choppin *
Department of Chemistry and Biochemistry, Florida State University, Tallahassee 32306-4390, FL, USA

a r t i c l e i n f o
Article history:
Received 8 June 2007
Accepted 17 March 2008
Available online 7 July 2008
Keywords:
Plutonium (IV)
Ternary complex
High ionic strength
Complexation thermodynamics

a b s t r a c t
The stability constants of the binary and the ternary complexes of Pu4+ have been measured for certain carboxylate and aminocarboxylate ligands in aqueous solution of I = 5.0 M (1 M perchloric acid + 4 M ionic strength perchlorate media) and temperatures of 0–45oC by the solvent extraction technique. The stability constants of the binary and the ternary complexes increased with increased temperature. The complexation enthalpy and entropy of the binary Pu–Ox and the ternary Pu–EDTA–Ox and DGA complexes indicated the stability of these complexes is due to the highly favorable entropy contribution while complexation enthalpies either oppose complexation or are weakly favorable.
_ 2008 Published by Elsevier B.V.

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Syntheses, structures and antimicrobial activities of various metal complexes of hinokitiol

2009-05-11T13:09:00.026+07:00

Kenji Nomiya *, Kuniaki Onodera, Ken Tsukagoshi, Kouhei Shimada, Akira Yoshizawa, Tada-aki Itoyanagi,
Akiyoshi Sugie, Shinichiro Tsuruta, Ryo Sato, Noriko Chikaraishi Kasuga
Department of Materials Science, Faculty of Science, Kanagawa University, Tsuchiya, Hiratsuka, Kanagawa 259-1293, Japan

a b s t r a c t
Metal–oxygen bonding complexes (M = MgII, MnII, NiII, MoVI, WVI, PdII, SbIII, BiIII, FeIII, TiIV, KI, BaII, ZrIV and HfIV) with a hinokitiol (Hhino; 2-hydroxy-4-isopropylcyclohepta-2,4,6-trienone or b-thujaplicin) ligand, which has two unequivalent oxygen donor atoms, were synthesized and characterized by elemental analysis, TG/DTA, FT-IR and solution (1H and 13C) NMR spectroscopy. Single-crystal X-ray structure analysis revealed various molecular structures for the complexes, which were classi.ed into several families of family, i.e. type A [MII(hino)2(L)]2 (M = MgII, MnII, NiII; L = EtOH or MeOH), with a dimeric structure consisting of one bridging hino_ anion, one chelating hino_ anion and one alcohol or water molecule, type B, with the octahedral, cis-dioxo, bis-chelate complexes cis-[MVIO2(hino)2] (M=MoVI, WVI), type C, with
square planar complex [MII(hino)2] (M=PdII), type D, with tris-chelate, 7-coordinate complexes with one inert electron pair [MIII(hino)3] (M= SbIII, BiIII), type D0, with the bis-chelate, pseudo-6-coordinate complexes with one inert electron pair [MIII(hino)2X] (M = SbIII, X = Br), type E, with tris-chelate, 6-coordinate complexes with D and K isomers [MIII(hino)3] (M= FeIII), type E0 of bis-chelate, 6-coordinate complex [MIV(hino)2X2] (M= TiIV, X = Cl), type F, with water-soluble alkali metal salts [MI(hino)] (M = KI), and type H, with tetrakis-chelate, 8-coordinate complexes [MIV(hino)4](M = ZrIV, HfIV). These structural
features were compared with those of metal complexes with a related ligand, tropolone (Htrop). The antimicrobial activities of these complexes, evaluated in terms of minimum inhibitory concentration (MIC; lgmL_1) in two systems, were compared to elucidate the relationship between structure and antimicrobial
activity.
_ 2008 Elsevier B.V. All rights reserved.

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Copper(II) acetate-induced hydrolytic C–N bond cleavage of a topologically constrained tetraaza macrotricycle

2009-05-11T13:09:00.025+07:00

Shin-Geol Kang *, Gyeong Rok Jeong
Department of Chemistry, Daegu University, Gyeongsan 712-714, Republic of Korea

a r t i c l e i n f o
Article history:
Received 19 September 2008
Accepted 11 November 2008
Available online 18 November 2008
Keywords:
Adjacent-bridged macrocycle
Topologically constrained macrocycle
C–N cleavage
Copper(II) complex

a b s t r a c t
A topologically constrained tetraaza macrotricycle, 2,2,4,10,10,12-hexamethyl-1,5,9,13-tetraazatricyclo[11.3.2.25.9]eicosane (L2), has been prepared by the reaction of 5,7,7,12,14,14-hexaazamethyl-1,4,8,11-tetraazacyclotetradecane (L1) with 1,3-dibromopropane. Interestingly, L2 reacts with Cu(OAc)2 H2O to produce [CuL3]2+ (L3 = 2,2,4,10,10,12-hexamethyl-1,5,9,13-tetraazabicyclo[11.3.2]octadecane) as the only product under mild conditions, showing that the C–N bonds at one of the two N–CH2CH2–N linkages
of the macrotricycle are readily broken in the presence of the metal salt. The complex [CuL3]2+ exhibits stronger ligand field strength than other related copper(II) complexes with a 5-6-6-6 chelate ring sequence and is unusually inert against decomposition in acid solutions.
_ 2008 Elsevier B.V. All rights reserved.

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Co(II)(L-proline)2(H2O)2 solid complex: Characterization, magnetic properties, and DFT computations. Preliminary studies of its use as oxygen scavenge

2009-05-11T13:09:00.024+07:00

Ziad Damaj a, Aude Naveau a,b, Laurent Dupont a, Eric Hénon a, Guillaume Rogez c, Emmanuel Guillon a,b,*
a Institut de Chimie Moléculaire de Reims (ICMR), Université de Reims Champagne-Ardenne, UMR CNRS 6229, Faculté des Sciences, BP 1039, F-51687 Reims Cedex 2, France
b ESIEC (Ecole Supérieure d’Ingénieurs en Emballage et Conditionnement), Pôle Technologique Henri Farman, BP 1029, F-51686 Reims Cedex 2, France
c Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 CNRS-ULP, 23 rue du Loess, BP 43, 67034 Strasbourg Cedex 2, France

a r t i c l e i n f o
Article history:
Received 29 August 2008
Accepted 23 October 2008
Available online 30 October 2008
Keywords:
Cobalt
Proline
Aminoacid
Oxygen scavenger
DFT

a b s t r a c t
A solid CoII complex with L-proline as ligand was synthesized and fully characterized using spectroscopic studies, magnetic data, and DFT calculations. Dioxygen scavenging properties were investigated by UV/Vis spectroscopy and oxymetry techniques. The Co-proline system presented very interesting properties in matter of oxygen absorption capacity both in solution and incorporated in a polymer matrix.
_ 2008 Elsevier B.V. All rights reserved.

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C–N-palladacyclic-catalyzed Heck reaction in EGME/water: Rate and regioselectivity controlled by the solvents ratio

2009-05-11T13:09:00.023+07:00

Alessandro Del Zotto a,*, Francesca Iogna Prat a, Walter Baratta a, Ennio Zangrando b, Pierluigi Rigo a
a Dipartimento di Scienze e Tecnologie Chimiche, Università di Udine, via Cotoni.cio 108, I-33100 Udine, Italy
b Dipartimento di Scienze Chimiche, Università di Trieste, via L. Giorgieri 1, I-34127 Trieste, Italy

a r t i c l e i n f o
Article history:
Received 30 January 2008
Received in revised form 3 March 2008
Accepted 5 March 2008
Available online 18 March 2008
Keywords:
Palladium complexes
Cyclometalated ligands
Homogeneous catalysis
Heck reaction

a b s t r a c t
Novel as well as known C,N-palladacyclic neutral complexes were tested as precatalyst in the Heck reaction between bromobenzene and styrene under aerobic conditions. The catalytic system Pd(II) complex/ K2CO3/EGME–H2O (EGME = ethylene glycol monomethyl ether) showed to be highly efficient. Best performances of the catalysts were achieved by controlling the amount of water: generally a H2O content within the 25–50% v/v range resulted in the highest conversion of the substrates into trans-stilbene. As a matter of fact, bromobenzene and styrene can be converted quantitatively using only 0.01 mol% of precatalyst with very high regioselectivity for the trans product and with a TOF of 10000 h_1. In the absenceof water, all complexes were less efficient and differences in their activity were found, while such a differentiation
disappeared when water was added.
_ 2008 Elsevier B.V. All rights reserved.

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Binuclear copper and zinc complexes based on polypyridyl ligand 2,3,5,6-tetra(2-pyridyl)pyrazine (tppz): Synthesis, spectral and structural characterization

2009-05-11T13:09:00.022+07:00

Manoj Trivedi a,*, Daya Shankar Pandey a, Nigam P. Rath b,*
a Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi 221 005, U.P., India
b Department of Chemistry and Biochemistry and Centre for Nanoscience, University of Missouri – St. Louis, One University, Boulevard, St. Louis, MO 63121-4499, USA

a r t i c l e i n f o
Article history:
Received 29 November 2007
Received in revised form 28 February 2008
Accepted 28 February 2008
Available online 7 March 2008
Keywords:
Metal complexes
2,3,5,6-Tetra(2-pyridyl)pyrazine (tppz)
ligand
X-ray
Weak interactions

a b s t r a c t
The reaction of MCl2 _ 2H2O (M = Cu, Zn) with 2,3,5,6-tetra(2-pyridyl)pyrazine (tppz) (referred hereafter as L) in 2:1 molar ratio in acetonitrile at room temperature afforded binuclear complexes [M2(j3-L)Cl4][Cu (1), Zn (2)] where the ligand is bis-tridentate manner. The complexes have been characterized by elemental analyses, FAB-MS, IR, EPR, NMR and electronic spectral studies. Solid state structures of both the [Cu2(j3-L)Cl4] _ 5H2O (1), [Zn2(j3-L)Cl4] _ H2O (2) have been determined by single crystal X-ray analyses. A well-resolved uudd cyclic water tetramer and water monomer were reported in the crystal host of
[Cu2(j3-L)Cl4] _ 5H2O (1) and [Zn2(j3-L)Cl4] _ H2O (2) showing the contribution of the water cluster to the stability of the crystal host 1 and 2.
_ 2008 Elsevier B.V. All rights reserved.

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A wide family of pyridoxal thiosemicarbazone ferric complexes: Syntheses, structures and magnetic properties

2009-05-11T13:09:00.021+07:00

Sébastien Floquet a,*, M. Carmen Muñoz b, Régis Guillot a, Eric Rivière a, Guillaume Blain a,
José-Antonio Réal c, Marie-Laure Boillot a
a ICMMO, Equipe Chimie Inorganique, UMR CNRS 8182, Univ. Paris-Sud, 91400 Orsay, France
b Departament de Fisica Aplicada, Universitat Politécnica de València, Cami de Vera s/n, 46022 València, Spain
c Universitat Valencia, Institut de Ciència Molecular/Departament de Quimica Inorganica, Edi.ci de Instituts de Paterna, Apartat de Correus 22085, València 46071, Spain

a b s t r a c t
This study reports the syntheses and the characterization of 12 ferric complexes of pyridoxal thiosemicarbazone. The richness of the coordination chemistry of this ligand is highlighted by the modulation of its charge from neutral H2L to anionic L2_, thus leading to a wide family of ferric compounds with charge varying from +3 to _1. The structures of complexes [Fe(HL)2]ClO4 _ 2H2O and [Fe(HL)L] _ 4.5H2O
were solved and discussed with a particular attention brought to the intermolecular interactions occurring between the complexes. The investigation of magnetic properties of these compounds revealed that two of them are in the HS state at any temperature, whereas the others are in the LS state. These results are discussed in relation to the modulation of the electronic properties of the ligand.

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A unique coordination chemistry of sodium

2009-05-11T13:09:00.020+07:00

Tanmay Chattopadhyay a, Kazi Sabnam Banu a, Soubhik Chattopadhyay c, Arpita Banerjee a,
Sandip Mondal a, Eringathod Suresh b,*, Debasis Das a,*
a Department of Chemistry, University of Calcutta, 92 A.P.C. Road, Kolkata 700 009, India
b Analytical Science Discipline, Central Salt and Marine Chemicals Research Institute, G.B. Marg, Bhavnagar 364 002, India
c Department of Physics, University of Calcutta, 92 A.P.C. Road, Kolkata 700 009, India

a b s t r a c t
A new coordination chemistry of sodium has been developed by complexing it with a non-chelating neutral nitrogen donor ligand hexamethylenetetramine (urotropine) in presence of cadmium(II) iodide and the new coordination compound has been characterized by X-ray single crystal structural analysis.
_ 2008 Elsevier B.V. All rights reserved.

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A phenyl-salicyliden-imine as a suitable ligand to build functional materials

2009-05-11T13:09:00.019+07:00

Archimede Rotondo a,*, Giuseppe Bruno a, Giovanna Brancatelli a,
Francesco Nicolo` a, Donatella Armentano b
a Dipartimento di Chimica Inorganica, Analitica e Chimica Fisica, Universita` di Messina, Salita Sperone 31, Vill. S. Agata, 98166 Messina, Italy
b Dipartimento di Chimica, Universita` della Calabria, Campus Arcavacata, via Bucci-87036, Cosenza, Italy
Received 29 October 2007; received in revised form 29 January 2008; accepted 31 January 2008

Abstract
The synthesis and characterization of 1,4-dicarboxy-phenyl-2-salicyliden-imine (DPSI), a new multi-functional and tridentate ligand, is presented together with the crystal structure of its copper(II) complex. DPSI chemical groups result very attractive because of the straightforward crystal engineering applications, so that we believe this is the first among a wide gamma of materials with promising
features and properties.
_ 2008 Elsevier B.V. All rights reserved.
Keywords: Crystal engineering; Schi.-base; Structural properties; Inorganic complexes

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A novel 3D coordination polymer [Cd15(l4-Mtta)12(l3-Mtta)6(l3-SO4)4(l3-OH)4]: Synthesis, structure and solid properties

2009-05-11T13:09:00.018+07:00

You-Bang Ding, Ying Cheng, Zhi-Ling Zhang, Jing Zhang, Ye-Gao Yin *, Wen-Hua Gao
Department of Chemistry, Shantou University, 243 University Road, Shantou 515063, Guangdong, PR China

a b s t r a c t
A 3D coordination polymer, {[Cd15(l4-Mtta)12(l3-Mtta)6(l3-SO4)4(l3-OH)4] _ 6H2O}n (1) (Mtta =5-methyl-tetrazolate), which shows the rare multifunction of in situ formed Mtta and bright photoinduced blue emission, was isolated from a hydrothermal reaction of CdSO4 _ 8/3H2O, NaN3 in acetonitrile and water.
_ 2008 Elsevier B.V. All rights reserved.

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A new two-dimensional manganese(II) coordination polymer with alternating double end-on and single end-to-end azido bridges

2009-05-11T13:09:00.017+07:00

Bao-Lin Liu a, Hong-Ping Xiao a, Emmanuel N. Nfor b, You Song a,*, Xiao-Zeng You a
a State Key Labortory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering,
Nanjing University, Nanjing 210093, China
b Department of Chemistry, University of Buea, Buea, P.O. Box 63, S.W. Province, Cameroon

a b s t r a c t
A new azido-bridged Mn(II) coordination polymer, [MnL(N3)2]n (1) (L = (E)-3-(dimethylamino)-1-(pyridin-2-yl)prop-2-en-1-one), has been synthesized and characterized by elemental analysis, IR, single crystal X-ray diffraction and magnetic measurement. X-ray analysis shows that complex 1 is a 2D network
with (6, 3) layers, in which double end-on (EO) azido-bridged dimers are linked by single end-to-end
(EE) azido bridges. Magnetic susceptibilities of 1 were measured under a magnetic .eld of 2 KOe applied over the temperature range 300–1.8 K. The analysis of magnetic data indicates that the EO- and EE-azido bridges mediate the ferromagnetic and antiferromagnetic exchange interactions, respectively, with the antiferromagnetic coupling between Mn(II) ions dominating the magnetic properties of 1.
_ 2008 Elsevier B.V. All rights reserved.

Trinuclear cobalt(II) sandwiched polyoxotungstobismuthate with antennal copper(II)-complex: A new method to combine hetero–transition–metallic ions

2009-05-11T13:09:00.016+07:00

Hong Liu a,*, Yan Liu a, Haiyan Liu a, Chunhui Shi b, Fenghua Liu a, Hongli Liu c
a College of Chemistry and Pharmacy, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China
b Clinic Medical College, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China
c Material College, Jiamusi University, Jiamusi, Heilongjiang 154007, PR China

a b s t r a c t
A new sandwich-type hybrid complex, Na8{Cu(im)4(H2O)}[Cu(im)4 {Na(H2O)2Co(im)}3(Bi- W9O33)2] _ 11H2O (1) (im = imidazole), has been synthesized and structurally characterized. The polyoxoanion in 1 contains trinuclear Co2+ ions in the central belt and an antennal Cu(II)–imidazole supported complex, which firstly represents a copper(II)-complex mono-supported tungstobismuthate system containing sandwiched trinuclear cobalt(II) ions. Neighboring polyanions further connect each other by disodium ions to yield a dimeric complex. The successful synthesis of 1 opens a new approach to the combination of different kinds of transition–metal ions by virtue of lacunary Keggin-type polyoxoanions, [BiW9O33]9_, as effective linkages. The magnetic investigation for 1 indicate weak antiferromagnetic interactions for trinuclear Co(II) clusters located in the polyanions.
_ 2008 Elsevier B.V. All rights reserved.

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An enantiomeric pair of sodium(I) organic/inorganic frameworks having novel two-dimensional inorganic comb-like separating layers

2009-05-05T20:46:00.003+07:00

Li Wang a, Zhaolian Chu a, Wei Huang a,*, Shaohua Gou a,b
a State Key Laboratory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering, Nanjing University,
Nanjing 210093, PR China
b College of Sciences, Nanjing University of Technology, Nanjing 210009, PR China

a b s t r a c t
An enantiomeric pair of sodium(I) directed organic/inorganic frameworks have been obtained via the Schiff base condensation between
terephthaldicarboxaldehyde and sodium salts of D- or L-phenylalanine wherein two novel two-dimensional (2D) inorganic sodium(I) separating layers composed of fully fused twelve-membered [Na6(H2O)12] comb-like rings are constituted. To the best of our knowledge, they are the first structural examples of
terephthaldicarboxaldehyde-based chiral Schiff base compounds and 2D [Nax(H2O)y]n robust inorganic frameworks.
_ 2008 Elsevier B.V. All rights

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