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Polyhedron (v.29, #5)

prelims, contents pages (pp. iii-viii).

CTAB-Mn3O4 nanocomposites: Synthesis, NMR and low temperature EPR studies by H. Kavas; Z. Durmus; M. Şenel; S. Kazan; A. Baykal; M.S. Toprak (pp. 1375-1380).
TEM analysis was performed to investigate the morphology and size of CTAB-Mn3O4 nanocomposites and a micrograph is presented in figure (a). The average particle size DTEM was calculated as 107.5±1.4nm for the CTAB-Mn3O4 nanocomposites using a log-normal fitting to the histograms obtained from several TEM micrographs.We are reporting on the synthesis of Mn3O4 nanoparticles and CTAB-Mn3O4 nanocomposites via a sonochemical route using MnCl2, ethanol, NaOH and CTAB. The crystalline phase was identified as Mn3O4. The crystallite size of the CTAB-Mn3O4 nanocomposite was identified as 13±5nm from X-ray line profile fitting and the particle size from TEM was 107.5±1.4nm. The interaction between CTAB and the Mn3O4 nanoparticles was investigated by FTIR and1H NMR spectroscopies. Two different magnetic phase transitions were observed for both samples below the Curie temperature (43°C) by using a low temperature Electron Paramagnetic Resonance (EPR) technique. Also we determined the effect of the capping with CTAB on the reduction in absorbed power.

Keywords: Nanostructures; Sonochemical synthesis; Nanocomposite; Mn; 3; O; 4; NMR; EPR


Barium bis(5,5-dimethyl-1,1,1-trifluorohexane-2,4-dionate)(crown-ether) complexes: Synthesis, characterization and crystal structure by Tatjana S. Pochekutova; Vyacheslav K. Khamylov; Yury A. Kurskii; Georgy K. Fukin; Boris I. Petrov (pp. 1381-1386).
The preparation of the barium β-diketonate complexes with crown-ethers [Ba(pta)2(18-crown-6)] (1), [Ba(pta)2(18-crown-6)] (THF) (2), [Ba(pta)2(18-dibenzocrown-6)](C6H5CH3) (3), [Ba(pta)2(18-dibenzocrown-6)] (4) (pta=1,1,1-trifluoro-5,5-dimethylhexanedionato-2,4 ; 18-crown-6=1,4,7,10,13,16-hexaoxacyclooctadecane; 18-dibenzocrown-6 = 6,7,9,10,17,18,20,21-octahydrodibenzo[b,k][1,4,7,10,13,16]- hexaoxacyclooctadecane) is described. The complexes were characterized by elemental analyses, IR-spectroscopy,1H NMR spectroscopy. The crystal structures of2,3 were determined by means of single-crystal X-ray diffraction methods.The preparation of the barium β-diketonate complexes with crown-ethers [Ba(pta)2(18-crown-6)] (1), [Ba(pta)2(18-crown-6)] (THF) (2), [Ba(pta)2(18-dibenzocrown-6)](C6H5CH3) (3), [Ba(pta)2(18-dibenzocrown-6)] (4) (pta=1,1,1-trifluoro-5,5-dimethylhexanedionato-2,4; 18-crown-6=1,4,7,10,13,16-hexaoxacyclooctadecane; 18-dibenzocrown-6=6,7,9,10,17,18,20,21-octahydrodibenzo[b,k][1,4,7,10,13,16]-hexaoxacyclooctadecane) is described. The complexes1 and2 have been synthesized from reaction of metallic barium with 2molar equiv. of Hpta and 1molar equiv. of 18-crown-6 in toluene; the complexes3 and4 from reaction of Ba(OH)2·8H2O with 1molar equiv. 18-dibenzocrown-6 and 2molar equiv. Hpta. The complexes were characterized by elemental analyses, IR-spectroscopy,1H NMR spectroscopy. The crystal structures of2 and3 were determined by means of single-crystal X-ray diffraction methods. A single-crystal X-ray study of2 and3 has shown it be monomeric. The coordination number of Barium cation in2 and3 is nine owing to nine oxygen atoms from two pta ligands and crown-ether molecule.

Keywords: Barium; β-Diketonate; Crown-ethers; Syntheses; X-ray diffraction


Synthesis, structures and magnetic properties of copper (II) and cobalt (II) complexes containing pyridyl-substituted nitronyl nitroxide and 3,5-dinitrobenzoate by Chen-Xi Zhang; Yu-Ying Zhang; Ya-Qiu Sun (pp. 1387-1392).
Four new metal-radical complexes have been synthesized by using transition metal ions and nitronyl nitroxide radicals as spin carriers, and incorporating 3,5-dinitrobenzoic acid (DTB) as a coligand. All the complexes show antiferromagnetic interactions. The correlation of crystal structures and magnetic properties in connection with the magnetic exchange mechanism is discussed.Four new metal-radical complexes - [Cu(NIT3Py)2(DTB)2]1, [Co(NIT3Py)2(DTB)2(CH3OH)2]2, [Cu(NIT4Py)2(DTB)2(H2O)2]3, [Co(NIT4Py)2(DTB)2(H2O)2]4, (NIT3Py=2-(3-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide], NIT4Py=2-(4-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide], DTB=3,5-dinitrobenzoic anion) have been synthesized by using transition metal ions, nitronyl nitroxide radicals as spin carriers, and incorporating 3,5-dinitrobenzoic acid (DTB) as a coligand.The structures of14 were determined by X-ray single-crystal analyses. Complex1 has a square planar geometry, where the Cu(II) ion is located in the central site of the rectangle and two radicals and two DTBA ligands are trans-coordinated to the Cu(II) ion. The other three complexes (2-4) have similar structures, in which two radicals, two DTBA ligands and two solvent molecules act as terminal ligands to form six coordinate distorted octahedrons. The magnetic behaviors of these compounds indicate that antiferromagnetic exchanges exist between the radical ligands and the metal ions, and their magnetic properties are explained by their structures and a magnetic exchange mechanism.

Keywords: Crystal structure; Nitronyl nitroxide metal complexes; Copper(II)/3,5-dinitrobenzoate complexes; Cobalt(II)/3,5-dinitrobenzoate complexes; Magnetism


Synthesis and characterization of some organotin(IV) adducts containing a related series of pyridines: Crystal structure of [SnMe2Cl2(bu2bpy)] by Badri Z. Momeni; Soheila Shahbazi; Hamid Reza Khavasi (pp. 1393-1398).
The synthesis and characterization of some penta- and hexa-coordinated organotin(IV) complexes obtained from the reaction of a series of pyridines, 4,4′-di-tert-butyl-2,2′-bipyridine, 4-tert-butylpyridine and 4,4′-trimethylenedipyridine, with SnR2Cl2 (R=Me, nBu) and SnPh3Cl are reported. The crystal structure of [SnMe2Cl2(bu2bpy)] shows that the coordination geometry about the tin atom is octahedral, with a trans-[SnMe2] moiety.Organotin(IV) complexes of [SnR(4− n)Cl n] ( n=2, R=Me, nBu; n=1, R=Ph) react with the bidentate pyridyl ligand 4,4′-di- tert-butyl-2,2′-bipyridine (bu2bpy) to give hexa-coordinated adducts with the general formula [SnR(4− n)Cl n(bu2bpy)]. However, the reaction of these organotin(IV) complexes with the corresponding monodentate ligand 4- tert-butylpyridine (bupy) resulted in the formation of the hexa-coordinated complex [SnMe2Cl2(bupy)2] and the penta-coordinated complexes [SnR(4− n)Cl n(bupy)] ( n=2, R= nBu; n=1, R=Ph). Moreover, the reaction of the above organotin(IV) complexes with 4,4′-trimethylenedipyridine (tmdp) yields hexa-coordinated adducts with the general formula [SnR2Cl2(tmdp)] (R=Me, nBu) and the penta-coordinated complex [ClPh3Sn-μ-(tmdp)SnPh3Cl] in the solid state. The resulting complexes have been characterized by multinuclear NMR (1H,13C,119Sn) spectroscopy and elemental analysis. NMR data shows that the triphenyltin(IV) adducts are not stable in solution and dissociate to give tetra-coordinated tin(IV) complexes. The X-ray crystal structure determination of [SnMe2Cl2(bu2bpy)] reveals that the tin atom is hexa-coordinated in an octahedral geometry with a trans-[SnMe2] configuration.

Keywords: Organotin; Adduct; Spectroscopy; Crystal structure; Geometry


Unsymmetrically substituted triazacyclohexanes and their chromium complexes by Saïda Latreche; Abdelhamid Mousser; Gabriele Kociok-Köhn; Randolf D. Köhn; Frank Schaper (pp. 1399-1404).
Unsymmetrically substituted alkyl-bis(aryl) triazacyclohexanes were obtained by selective crystallisation from equilibrated mixtures. Reactions of these ligands with chromium trichloride afforded pure, but insoluble (TAC)CrCl3 complexes.The unsymmetrically N-substituted N,N′-Ar2-N″-R-1,3,5-triazacyclohexanes14 (Ar= ortho- or para-fluorophenyl, R= n- or iso-propyl) can be obtained in good yields from a one-step condensation reaction with excess amine. Solid state structures of14 resemble closely those of their triaryl-substituted analogues. The condensation reaction to4 was looked at by detailed NMR investigations and revealed that amine/aniline exchange is occurring in solutions containing free aniline even at ambient conditions setting up an equilibrium between all possible symmetrical and unsymmetrical triazacylcohexanes. Selective crystallisation of4 from the solution drives the reaction to high yields of4. Complexes14 react readily with CrCl3 or CrCl3(THF)3 to form the corresponding CrCl3 complexes. The complexes are insoluble in non-polar solvents and decompose under decomplexation in coordinating solvents.

Keywords: Triazacyclohexane; Chromium complexes; Chromium(III); Selective crystallisation


XRD structure of two heptacoordinated Mn(II) complexes containing 2,9-dimethyl-1,10-phenanthroline (phen), nitrato and nicotinato bidentate anions: [Mn(phen)(nicot)(NO3)(H2O)]·EtOH·H2O and [Mn(phen)(NO3)2(H2O)] by Nabila El-Azzouzi; Francisco Hueso-Ureña; Nuria A. Illán-Cabeza; Miguel N. Moreno-Carretero (pp. 1405-1410).
The structure of two seven-coordinated Mn(II) complexes with the formula [Mn(phen)(nicot)(NO3)(H2O)] and [Mn(phen)(NO3)2(H2O)] (phen=2,9-dimethyl-1,10-phenanthroline) are reported. Both coordination polyhedra are intermediate between pentagonal bipyramidal (apical sites occupied by a nitrogen from phen and the water molecule) and square-capped trigonal prismatic, the capping site being occupied by the water molecule.The XRD structure of two seven-coordinated Mn(II) complexes with the formula [Mn(phen)(nicot)(NO3)(H2O)]·EtOH·H2O (1) and [Mn(phen)(NO3)2(H2O)] (2) are reported. The 2,9-dimethyl-1,10-phenanthroline, nitrato and nicotinato anions act as bidentate ligands, with Mn–N distances of 2.21–2.29Å and Mn–O distances of 2.17–2.40Å. In both compounds, the water molecule seems to be the strongest coordinated ligand, with bond distances of 2.139(2)Å in1 and 2.195(2)Å in2. The average ratio between coordinated unidentate and bidentate bond lengths less than the unity justifies, from an energetical point of view, the shape of the coordination polyhedra. In the structure of1, the coordination polyhedron may be best-described as a distorted pentagonal bipyramid with a nitrogen from phenanthroline and the water molecule occupying the apical sites. The polyhedron shape for2 is close to a square-capped trigonal prism, the capping site being occupied by the water molecule. The crystal structures are built by H-bonded bidimensional sheets piled up by ππ stacking of the partially interpenetrated aromatic moieties of adjacent layers.

Keywords: Crystal structure; DNA intercalators; Manganese complexes; Nicotinic acid; Phenanthroline


The synthesis and characterization of aluminum, gallium and zinc formamidinates by Leslie A. Lesikar; Anne F. Richards (pp. 1411-1422).
Nine aluminum, gallium and zinc complexes with the bulky formamidinate ligand RN(H)C(H)NR, (R=2,6-diisopropylphenyl), have been synthesized and characterized. The monodentate, bidentate chelating, and bimetallic bridging coordination modes of the ligand are observed, as well as mono- and di-oxygenated tetranuclear zinc clusters and an Al3 hydroxide cluster supported by two formamidinate ligands.Reactions of the formamidinate ligand, RN(H)C(H)NR, LH, (R=2,6-diisopropylphenyl), with AlMe3, AlMe2Cl, GaMe3 and ZnEt2 were investigated to examine potential coordination modes of the ligand and the effect of hydrolysis on the products. Nine new complexes have been fully characterized by X-ray crystallography and other spectroscopic techniques and highlight the diverse coordination modes of the formamidinate ligand.

Keywords: Formamidinate; Aluminum and zinc alkyls; Crystal structures


Rhenium(I), (III) and (V) complexes of tridentate ONX (X=O, N, S)-donor Schiff bases by P. Mayer; K.C. Potgieter; T.I.A. Gerber (pp. 1423-1430).
Complexes of rhenium(I), (III) and (V) with tridentate ONX-donor Schiff bases (X = O, N, S) have been synthesized from [ReOBr3(PPh3)2] and [Re(CO)5Br].The reactions of the potentially tridentate Schiff bases 2-[(2-hydroxyphenyl)iminomethyl]phenol (H2ono) and 2-(2-aminobenzylideneimino)phenol (H3onn) with trans-[ReOBr3(PPh3)2] were studied, and the complexes [ReIIIBr(PPh3)2(ono)] (1) and [ReVBr(PPh3)2(onn)]Br (2) were isolated. In1 ono acts as a dianionic tridentate ligand, and in2 onn is coordinated as a tridentate trianionic imido-imino-phenolate. The complex [ReI(CO)3(ons)(Hno)] was isolated from the reaction of [Re(CO)5Br] with 2-[(2-methylthio)benzylideneimino]phenol (Hons; Hno=2-aminophenol), with ons coordinated as a bidentate chelate with a free SCH3 group. These complexes were characterized by X-ray crystallography, NMR and IR spectroscopy.

Keywords: Rhenium(I, III, V); Tridentate Schiff bases; Multidentate imido chelate; X-ray structures


Synthesis and characterization of metal complexes of N-alkyl- N-phenyl dithiocarbamates by Damian C. Onwudiwe; Peter A. Ajibade (pp. 1431-1436).
Zn(II), Cd(II) and Hg(II) complexes of N-ethyl- N-phenyl dithiocarbamate and N-butyl- N-phenyl dithiocarbamate have been synthesized and characterized by analytical and spectroscopic techniques. Single crystal X-ray structures of the zinc complexes are also reported. The dimeric molecules revealed a distorted trigonal bipyramidal and tetrahedral coordination geometry respectively around the zinc metal ions.Ammonium N-ethyl- N-phenyl dithiocarbamate (L1) and N-butyl- N-phenyl dithiocarbamate (L2), and their group 12 metal complexes formulated asZn2L14,CdL12,HgL12,Zn2L24,CdL22,HgL22 have been synthesized and characterized by elemental analyses, IR,1H and13C NMR spectroscopy. The crystal structures of the zinc complexes (Zn2L14 andZn2L24) are also reported. Single crystal analyses of the two complexes revealed the presence of distorted trigonal bipyramidal and tetrahedral coordination geometry about the metal ions. The dithiocarbamate acts as bidentate chelating and bidentate bridging ligands between the metal ions giving centrosymmetric dimeric molecules. The apparent substitution of the ethyl substituents inL1 by the butyl groups inL2 results in profound change in structure.

Keywords: Crystal structures; Dithiocarbamates; Metal complexes; X-ray diffraction


Dimeric and polymeric silver(I) saccharinato complexes of two bis(pyridine) ligands: Synthesis, structural, spectroscopic, fluorescent and thermal properties by Emel Guney; Veysel T. Yilmaz; Orhan Buyukgungor (pp. 1437-1442).
Two new silver(I) complexes [Ag2(sac)2(bpeh)] (1) and [Ag(sac)(bpma)] n (2) have been synthesized and structurally characterized. Complex1 shows a binuclear composition, while2 is a one-dimensional helical polymer. Both complexes show conformational chirality.The reaction of silver(I) with 1,2-bis[1-(pyridin-2-yl)ethylidene]hydrazine (bpeh) and N, N-bis(pyridin-2-ylmethyl)amine (bpma) in the presence of Na(sac) (sac=saccharinate) yielded [Ag2(sac)2(bpeh)] (1) and [Ag(sac)(bpma)] n (2) with conformational chirality. Both complexes have been characterized by elemental analysis, IR, thermal analysis and X-ray single crystal diffraction. Complex1 displays a binuclear composition, in which each silver(I) ion is bound to one monodentate sac ligand and one of the bidentate pyridylimino groups of the bpeh ligand in a distorted trigonal coordination geometry. Complex2 is a one-dimensional helical polymer, in which silver(I) centers are bridged by tridentate bpma ligands, and each silver(I) ion is coordinated in a distorted tetrahedral geometry by one monodentate sac ligand, a bidentate pyridylamine group of one bpma ligand, and a py group of another bpma ligand. Weak intermolecular C–H⋯O hydrogen bonds and C–H⋯π interactions lead to assembly of1 and2 into three-dimensional supramolecular frameworks. Spectral and thermal analysis data for1 and2 are in agreement with the crystal structures. In addition, both complexes in the solid state display intraligand π–π∗ fluorescence.

Keywords: Saccharinate; 1,2-Bis[1-(pyridin-2-yl)ethylidene]hydrazine; N; ,; N; -bis(pyridin-2-ylmethyl)amine; Chirality; Coordination polymer; Silver(I)


Osmium(VIII) catalysed and uncatalysed oxidation of aspirin drug by diperiodatocuprate(III) complex in aqueous alkaline medium: A mechanistic approach by Ragunatharaddi R. Hosamani; R.T. Mahesh; Sharanappa T. Nandibewoor (pp. 1443-1452).
The kinetics of oxidation of aspirin drug by diperiodatocuprate(III) (DPC) in presence and absence of osmium(VIII) catalyst has been studied in aqueous alkaline medium. Where as DPC is considered to be the active species and active species of Os(VIII) is [OsO4(OH)2]2−.The kinetics of oxidation of a non-steroidal analgesic drug, aspirin (ASP) by diperiodatocuprate(III)(DPC) in the presence and absence of osmium(VIII) have been investigated at 298K in alkaline medium at a constant ionic strength of 0.10moldm−3 spectrophotometrically. The reaction showed a first-order in [DPC] and less than unit order in [ASP] and [alkali] for both the osmium(VIII) catalysed and uncatalysed reactions. The order with respect to Os(VIII) concentration was unity. The effects of added products, ionic strength, periodate and dielectric constant have been studied. The stoichiometry of the reaction was found to be 1:4 (ASP:DPC) for both the cases. The main oxidation product of aspirin was identified by spot test, IR, NMR and GC–MS. The reaction constants involved in the different steps of the mechanisms were calculated for both reactions. Activation parameters with respect to slow step of the mechanisms were computed and discussed for both the cases. The thermodynamic quantities were also determined for both reactions. The catalytic constant ( KC) was also calculated for catalysed reaction at different temperatures and the corresponding activation parameters were determined.

Keywords: Aspirin; Os(VIII) catalysis; Diperiodatocuprate(III); Oxidation; Mechanistic


Piperazinediium, Zr(IV) and Ce(IV) pyridine-2,6-dicarboxylates: Syntheses, characterizations, crystal structures, ab initio HF, DFT calculations and solution studies by Hossein Aghabozorg; Elham Motieiyan; Ali R. Salimi; Masoud Mirzaei; Faranak Manteghi; Ardeshir Shokrollahi; Somayeh Derki; Mohammad Ghadermazi; Shabnam Sheshmani; Hossein Eshtiagh-Hosseini (pp. 1453-1464).
Three compounds, (pipzH2)1.5(pydcH)3·3.7H2O,1, (pipzH2)[Zr(pydc)3]·8H2O,2 and (pipzH2)[Ce(pydc)3]·8H2O,3 in which pydcH2 is pyridine-2,6-dicarboxylic acid and pipz is piperazine, are obtained in aqueous solution. The compounds are characterized by IR,1H NMR and13C NMR spectroscopy, elemental analyses, and X-ray crystallography. They are investigated by theoretical calculations and solution studies.The novel title compounds, (pipzH2)1.5(pydcH)3·3.7H2O,1, (pipzH2)[Zr(pydc)3]·8H2O,2 and (pipzH2)[Ce(pydc)3]·8H2O,3 in which pydcH2 is pyridine-2,6-dicarboxylic acid and pipz is piperazine were obtained in aqueous solution. The compounds were characterized by IR,1H NMR and13C NMR spectroscopy, elemental analyses, and X-ray crystallography. Compound1 is resulted from proton transfer between pydcH2 and pipz. However, compounds2 and3 are resulted from complexation of1 and corresponding metallic salts. Both compounds2 and3 contain three pyridine-2,6-dicarboxylate species as tridentate ligands, one piperazinediium as counter ion, and eight-uncoordinated water molecules in the asymmetric unit. In both structures each M(IV) is coordinated in a distorted tricapped trigonal prism geometry by three nitrogen and six oxygen atoms of carboxylate groups of three (pydc)2− fragments. In the crystal structures of1,2 and3, extensive O–H···O, N–H···O and C–H···O hydrogen bonds as well as electrostatic forces, C–H···π, C–O···π and π–π stacking play important roles in stabilizing structures. The geometrical parameters of the [M(pydc)3]2− anionic complexes, where M=Ce(IV), Zr(IV) have been optimized with the B3LYP method of density functional theory (DFT) and ab initio Hartree–Fock (HF) methods for comparison. In addition, we have studied the structures of (pydc)2− anion and its mono and doubly protonated forms, (pydcH) and pydcH2. The electronic properties of the anionic complexes and ligands have been investigated based on the natural bond orbital (NBO) analysis at the B3LYP method which verifies that the synergistic effect has been occurred in the title complexes. In solution study of2, the stoichiometry and stability constant of complexation of pipz, pydc, pydc–pipz proton transfer system and Zr(IV) ion in aqueous solution were investigated by potentiometric method.

Keywords: Zirconium; Cerium; Hydrogen bonds; Crystal structure; Ab initio; calculation; Solution studies


Synthesis and characterization of new air stable primary amido substituted diborane(4) derivatives by Erkan Fırıncı; H. Can Söyleyici; Emrah Giziroğlu; Ersin Temel; Orhan Büyükgüngör; Yüksel Şahin (pp. 1465-1468).
New air stable primary amido substituted diborane(4) derivatives were prepared and characterized by elemental analysis, IR,1H,13C and11B NMR spectroscopy. The structures of two compounds were determined by X-ray diffraction.Three new diborane(4) derivatives, 1,2-bis(2,4,6-trimethylanilide)-1,2-bis(dimethyamido)diborane(4) (1), 1,2-bis(2,4,6-trimethylanilide)-1,2-bis(duryl)diborane(4) (2) and 1,2-bis(anilide)-1,2-bis(duryl)diborane(4) (3), have been synthesized and characterized by means of elemental analysis, IR,1H,13C and11B NMR spectroscopy. Additionally, the structures of compounds1 and2 have been determined by the single crystal X-ray diffraction technique. The compounds1 and2 crystallize in the monoclinic P21/c space group. All of the compounds were found to be air stable.

Keywords: Boranes; Diborane(4); Air stable; X-ray structures


Spectroscopic studies of nanostructures of negatively charged free base porphyrin and positively charged tin porphyrins by Reama C. George; Gabriel O. Egharevba; Tebello Nyokong (pp. 1469-1474).
A mixture of negatively charged free base protonated meso-tetraphenylsulfonated porphyrin ([H4TPPS4]2−) and tin meso-tetra (N-methyl-4-pyridyl) porphyrin ([SnTMPyP]4+) forms heteroaggregates of the J type in acid media whose Raman microscopic image shows leaf-like structure.Spectroscopic studies were carried out on the homoaggregates of negatively charged free base meso-tetraphenylsulfonated porphyrin ([H2TPPS4]4−) and heteroaggregates of a mixture of protonated ([H4TPPS4]2−) and tin meso-tetra (N-methyl-4-pyridyl) porphyrin ([SnTMPyP]4+). The spectroscopic studies were done to determine the optimal conditions required for the fabrication of porphyrin nanorods by ionic self assembly of two oppositely charged porphyrins. In addition, the various spectral changes of [H4TPPS4]2− with concurrent change in pH and concentration are also investigated. In acid media at pH <3, and at concentrations >1×10−5 M, [H4TPPS4]2− molecules form J aggregates. A mixture of [H4TPPS4]2− and [SnTMPyP]4+ forms heteroaggregates of the J type in acid media. At pH’s 2 to 3, the optimum ratio for the formation of J aggregates is 3:1 and for pH 1, the optimum ratio is 2:1. Transmission electron microscope images of the nanostructures formed show that they are of cylindrical shape.

Keywords: Free base meso-tetraphenylsulfonated porphyrin; Tin meso-tetra (N-methyl-4-pyridyl) porphyrin; Electronic spectra; Raman microscope image; Transmission electron microscopy


Synthesis, electrochemical, in situ spectroelectrochemical and in situ electrocolorimetric characterization of new metal-free and metallophthalocyanines substituted with 4-{2-[2-(1-naphthyloxy)ethoxy]ethoxy} groups by Irfan Acar; Zekeriya Bıyıklıoğlu; Atıf Koca; Halit Kantekin (pp. 1475-1484).
The synthesis of novel metal-free and metallophthalocyanines [Ni(II), Zn(II), Co(II), Cu(II)] were prepared by cyclotetramerization of a novel 4-{2-[2-(1-naphthyloxy)ethoxy]ethoxy}phthalonitrile and the corresponding metal salts (NiCl2, Zn(CH3COO)2, CoCl2 and CuCl2). The structures of the target compounds were confirmed using elemental analysis, IR,1H NMR,13C NMR, UV–Vis and MS spectral data. Voltammetric and in situ spectroelectrochemical measurements show that while cobalt phthalocyanine complex gives both metal-based and ring-based redox processes, metal-free, and zinc phthalocyanines show only ring-based reduction and oxidation processes. All complexes decomposed and coated on the electrode as nonconductive film at positive potential window of the electrolyte. An in situ electrocolorimetric method has been applied to investigate color of the electro-generated anionic and cationic forms of the complexes.The synthesis of novel metal-free and metallophthalocyanines [Ni(II), Zn(II), Co(II), Cu(II)] were prepared by cyclotetramerization of a novel 4-{2-[2-(1-naphthyloxy)ethoxy]ethoxy}phthalonitrile and the corresponding metal salts (NiCl2, Zn(CH3COO)2, CoCl2 and CuCl2). The structures of the target compounds were confirmed using elemental analysis, IR,1H NMR,13C NMR, UV–Vis and MS spectral data. Voltammetric and in situ spectroelectrochemical measurements show that while cobalt phthalocyanine complex gives both metal-based and ring-based redox processes, metal-free, and zinc phthalocyanines show only ring-based reduction and oxidation processes. All complexes decomposed and coated on the electrode as nonconductive film at positive potential window of the electrolyte. An in situ electrocolorimetric method has been applied to investigate color of the electro-generated anionic and cationic forms of the complexes.

Keywords: Phthalocyanine; Phthalonitrile; Cyclic voltammetry; Synthesis; Spectroelectrochemistry; Chromaticity diagram


Anisotropy and magnetic properties of the bimetallic thiocyanate-bridged chains: Density-matrix renormalization approach by Artur Barasiński; Paweł Sobczak; Andrzej Drzewiński; Grzegorz Kamieniarz; Alina Bieńko; Jerzy Mroziński; Dante Gatteschi (pp. 1485-1491).
Crystal packing of {CuLα[Ni(NCS)4(H2O)2]}. This compound is isostructural with the complex {CuLα[Mn(NCS)4(H2O)2].Magnetic properties of bimetallic thiocyanate-bridged chains are numerically analyzed on the basis of the one-dimensional quantum anisotropic Heisenberg model without the mean-field corrections. The single-ion and g factor anisotropy of the metal ions (Co(II), Mn(II), Ni(II)) are taken into account. The thermodynamic properties are calculated using the DMRG technique, which is reliable in the entire temperature region, adapted to the molecular-based chains. The high accuracy results of our simulations are successfully fitted to the corresponding experimental susceptibility and magnetization data measured for a powder sample. Our analysis permitted determination of the microscopic parameters (the strength of magnetic couplings between the copper and metal ions and the single-ion anisotropy terms) as well as the corresponding g factors which are consistent with the values known for other compounds.

Keywords: Crystal structure; Heterobimetallic chain; Thiocyanate bridge; Magnetism; DMRG technique; Single-ion anisotropy of Co(II), Mn(II), Ni(II) ions


Meso-tetracinnamylporphyrin: Synthesis, characterization and the catalytic activity of its Mn(III) complex in olefin epoxidation with tetra-n-butylammonium hydrogen monopersulfate by Saeed Zakavi; Amir Salami Ashtiani; Saeed Rayati (pp. 1492-1496).
Synthesis and characterization of meso-tetracinnamylporphyrin (H2tcp) as a fully conjugated porphyrin is reported. The blue shift of the Q(0,0) band of H2tcp upon diprotonation with HCl shows evidence of a decrease in the efficiency of the π-electron donation to the porphyrin core in comparison with meso-tetraphenylporphyrin (H2tpp). Mntcp(OAc) shows greater catalytic activity than Mntpp(OAc) for the oxidation of olefins with tetra-n-butylammonium hydrogen monopersulfate. Meso-tetracinnamylporphyrin (H2tcp) has been synthesized and characterized by UV–Vis,1H NMR and IR spectroscopies. Protonation of H2tcp with HCl is accompanied by a blue shift (77cm−1) of the Q(0,0) band, probably indicating a decrease in the efficiency of the π-electron donation from the meso-substituents to the a2u orbital in comparison with the corresponding dication of meso-tetraphenylporphyrin (H2tpp). The unusual NH signal multiplicity observed in1H NMR spectrum of H2tcp shows evidence of a long distance coupling between the vinyl protons and NH ones. This long range coupling can occur between the remote centers using the a2u orbital as a connector. Mntcp(OAc) shows higher catalytic activity (ca. 1.2-fold higher) than Mntpp(OAc) in olefin epoxidation with tetra-n-butylammonium hydrogen monopersulfate (TBAO). The low ratio (∼1.5) of cis- to trans-stilbene oxide, in competitive oxidation of cis- and trans-stilbene with TBAO, strongly suggests the involvement a common high-valent manganese oxo complex as the reactive intermediate responsible for oxygen atom transfer.

Keywords: Meso; -tetracinnamylporphyrin; Epoxidation; Tetra-n-butylammonium hydrogen monopersulfate; Dication; Meso; -tetracinnamylporphyrinatomanganese(III) acetate


Chiral C1-symmetric 2,2′:6′,2′′-terpyridine ligands: Synthesis, characterization, complexation with copper(II), rhodium(III) and ruthenium(II) ions and use of the complexes in catalytic cyclopropanation of styrene by Chi-Tung Yeung; Wing-Sze Lee; Chui-Shan Tsang; Shek-Man Yiu; Wing-Tak Wong; Wai-Yeung Wong; Hoi-Lun Kwong (pp. 1497-1507).
Three new optically pure C1-terpyridine ligands (L13) were prepared and the copper(II) complexes, of formula [Cu(L)Cl2], the rhodium(III) complexes, of formula [Rh(L)Cl3], and the ruthenium(II) complexes, of formula cis- or trans-[Ru(L)(X)Cl2] ( X=DMSO or CO), were synthesized. Structures of a chiral C1-ligand, a copper complex, a rhodium complex and a ruthenium DMSO complex were analysed using X-ray crystal structure analysis. The copper, rhodium and ruthenium complexes were shown to be precursors of catalysts for cyclopropanation.Three new optically pure C1-terpyridine ligands (L13) were prepared and the copper(II) complexes, of formula [Cu(L)Cl2], the rhodium(III) complexes, of formula [Rh(L)Cl3], and the ruthenium(II) complexes, of formula cis- or trans-[Ru(L)(X)Cl2] (X=DMSO or CO), were synthesized. Structures of a chiral C1-ligand, a copper complex, a rhodium complex and a ruthenium DMSO complex were analysed using X-ray crystal structure analysis. The copper, rhodium and ruthenium complexes were shown to be precursors of catalysts for cyclopropanation. Reaction of [Cu(L)Cl2], [Rh(L)Cl3] or cis- or trans-[Ru(L)(X)Cl2] with AgOTf converted the complex to catalyst, which in the case of trans-[Ru(L)(CO)Cl2] gave enantioselectivities of up to 67% ee for the cis-isomers of styrene cyclopropanes with t-butyl diazoacetate. Comparisons with C2-analog of copper, rhodium and ruthenium catalysts were made.

Keywords: Chiral terpyridine; Copper; Rhodium; Ruthenium; Metal-catalyzed cyclopropanation; Asymmetric catalysis


Synthesis and structural characterization of novel ruthenium(II) complexes featuring an N, N, O-scorpionate ligand: A versatile synthetic precursor for open-face scorpionatoruthenium(II) complexes by Akira Yogi; Jae-Hwan Oh; Takanori Nishioka; Rika Tanaka; Eiji Asato; Isamu Kinoshita; Satoshi Takara (pp. 1508-1514).
Syntheses and characterization of novel ruthenium(II) complexes bearing bis(3,5-dimethylpyrazol-1-yl)acetato (bdmpza), a new class of scorpionate ligands, are described. [RuCl(bdmpza)(η4-1,5-cyclooctadiene)] is a versatile precursor that allows us a new synthetic route to obtain a wide variety of ruthenium(II) complexes with the bdmpza ligand.The syntheses and characterization of novel ruthenium(II) complexes containing bis(3,5-dimethylpyrazol-1-yl)acetato (bdmpza), a new class of scorpionate ligands, are reported herein. [RuCl(bdmpza)(η4-1,5-cyclooctadiene)] (1) was found to be a versatile precursor to synthesize a wide range of new ruthenium(II) complexes with the bdmpza ligand. The treatment of1 with pyridine (py), diphenylphosphinoethane (dppe), 2,2′-bipyridyl (bpy), 1,10-phenanethroline (phen), or bispicolylamine (Hbpica) in refluxing N, N-dimethylformamide resulted in displacement of the 1,5-cyclooctadiene ligand to afford [RuCl(bdmpza)(py)2] (2), [RuCl(bdmpza)(dppe)] (3), [RuCl(bdmpza)(bpy)] (4), [RuCl(bdmpza)(phen)] (5), and [Ru(bdmpza)(Hbpica)]Cl (6Cl) in good yields, respectively. The structures of14, and6 were determined by X-ray structure analyses.

Keywords: N; ,; N; ,; O; -scorpionate ligand; Ru(II) complex; Ligand substitution; Crystal Structure


Synthesis and characterization of Zn(II), Cd(II) and Ni(II) complexes with N-thiophosphorylated thioureas RC(S)NP(S)(O iPr)2 (R=MeNH, 2-MeC6H4NH, 2,6-Me2C6H3NH, 2,4,6-Me3C6H2NH, 2-Py(6-Me)NH) by Maria G. Babashkina; Damir A. Safin; Michael Bolte; Axel Klein (pp. 1515-1519).
Reaction of the potassium salts of RC(S)NHP(S)(O iPr)2 (R=MeNH,HLI; 2-MeC6H4NH,HLII; 2,6-Me2C6H3NH,HLIII; 2,4,6-Me3C6H2NH,HLIV; 2-Py(6-Me)NH,HLV) with Zn(II) and Cd(II) in aqueous EtOH leads to the complexes [Zn(LI–V- S, S′)2] ([ZnLI–V2]) and [Cd(LI–V- S, S′)2] ([CdLI–V2]). Reaction ofKLV with Ni(II) in aqueous EtOH leads to the complex Ni[2-Py(6-Me)NHC(S)NP(S)(O iPr)2- N( Py), N( P), S]2 ([NiLV2]). The molecular structure of[ZnLV2] was elucidated by single crystal X-ray diffraction. Colorless and air/moisture stable chelate complexes of divalent zinc and cadmium show blue emission in the solid state when excited with UV light.Reaction of the potassium salts of N-thiophosphorylthioureas RC(S)NHP(S)(O iPr)2 (R=MeNH,HLI; 2-MeC6H4NH,HLII; 2,6-Me2C6H3NH,HLIII; 2,4,6-Me3C6H2NH,HLIV; 2-Py(6-Me)NH,HLV) with Zn(II) and Cd(II) in aqueous EtOH leads to the complexes [Zn(LI–V- S, S′)2] ([ZnLI–V2]) and [Cd(LI–V- S, S′)2] ([CdLI–V2]). Reaction of the potassium saltKLV with Ni(II) in aqueous EtOH leads to the complex [Ni(2-Py(6-Me)NHC(S)NP(S)(O iPr)2- N( Py), N( P), S)2] ([NiLV2]), where the metal cation is coordinated by two deprotonated ligandsLV through the pyridine and phosphorylamide nitrogen atoms, and the PS sulfur atoms. The structures of the new complexes were studied by NMR spectroscopy; their compositions were examined by microanalysis. The molecular structure of[ZnLV2] was elucidated by single crystal X-ray diffraction. The metal center is found in a tetrahedral S4 environment formed by the CS and PS sulfur atoms of two deprotonated ligandsLV. The colorless and air/moisture stable chelate complexes of divalent zinc and cadmium show blue emission in the solid state when excited with UV light.

Keywords: Zinc(II); Cadmium(II); Nickel(II); Coordination chemistry; Crystal structure; N; -Thiophosphorylthiourea; Luminescence


Sonochemical syntheses of a straw-like nano-structure two-dimensional mixed-ligand zinc(II) coordination polymer as precursor for preparation of nano-sized ZnO by Mojtaba Khanpour; Ali Morsali; Pascal Retailleau (pp. 1520-1524).
Straw-like nano-structure of a new mixed-ligand Zn(II) two-dimensional coordination polymer {[Zn(μ-4,4′-bipy)(μ-3-bpdb)(H2O)2](ClO4)2·4,4′-bipy·3-bpdb·H2O} n (1), {4,4′-bipy=4,4′-bipyridine and 3-bpdb=1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene} was synthesized by a sonochemical method. The new nano-structure was characterised by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses.Straw-like nano-structure of a new mixed-ligand Zn(II) two-dimensional coordination polymer, {[Zn(μ-4,4′-bipy)(μ-3-bpdb)(H2O)2](ClO4)2·4,4′-bipy·3-bpdb·H2O} n (1) {4,4′-bipy=4,4′-bipyridine and 3-bpdb=1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene}, was synthesized by a sonochemical method. The new nano-structure was characterised by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analyses. Compound1 was structurally characterised by single crystal X-ray diffraction and consists of two-dimensional polymeric units. ZnO nanoparticles were obtained by calcination of compound1 at 500°C under air atmosphere and were characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM).

Keywords: Nano-structure; 4,4′-Bipyridine; 1,4-Bis(3-pyridyl)-2,3-diaza-1,3-butadiene; Coordination polymer; Zinc(II); Zinc(II) oxide


Preparation of heterodinuclear complexes with phenol-based compartmental ligands containing hexa- and tetradentate coordination sites by Hamid Golchoubian; Leila Rostami; Benson Kariuki (pp. 1525-1533).
A series of mono- and heterodinuclear complexes of type ML nH2 and ML nM′ where M=CoIII, CrIII, ZnII and M′=CuII, ZnII have been synthesized and characterized. The crystal structure of [CrIIIL2H2]ClO4 was determined and discussed.A series of mono- and heterodinuclear complexes of type ML nH2 and ML nM′ where M=CoIII, CrIII, ZnII and M′=CuII, ZnII have been synthesized and characterized. The non-macrocyclic ligands L nH4 contain two geometrically distinct compartments, hexa- (N4O2) and tetradentate (O4) compartments which are bridged by phenolic oxygen atoms. The dinuclear complexes were prepared in stepwise reactions. The non-macrocyclic ligand showed a site specificity of metal ions upon the synthetic procedure. The results obtained reveals that in case of using ligand L2H4 only an isomer ( trans-pyridines and cis-phenolates) among three possible geometrical isomers is formed. The metal site scrambling in the prepared complexes were not also observed in the reaction conditions used. The crystal structure of [CrIIIL2H2]ClO4 was determined and discussed.

Keywords: Heterodinuclear complexes; Phenol-based ligand; Compartmental ligand; Site-specific; Metal site scrambling; Crystal structure

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