bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adolf Butenandt und sein Wirken an der Technischen Hochschule Danzig
Authors: Piosik Romuald 
Published: July 2003

AbstractDAS JAHR 2003 ist in Deutschland das Jahr der Chemie. Es ist auch ein Jahr, in dem wir drei der berühmtesten Chemiker der Welt gedenken: Justus Liebig, Wilhelm Ostwald und Adolf Butenandt. Letzterem verdanken wir die Isolierung und Aufklärung der Sexualhormone und einer Vielzahl weiterer Naturstoffe. Einen wesentlichen Teil seiner Forschungsergebnisse hat er an der Technischen Hochschule zu Danzig gewonnen.
Theory of magnetic islands in tokamaks with accenting neoclassicaltearing modes
Authors: Mikhailovskii A.B. 
Published: July 2003

AbstractKey aspects of existing theory of magnetic islands in tokamaks are overviewed. The threshold models of neoclassical tearing modes (NTMs) are discussed. It is found that though the NTM theory is often used for interpreting MHD data observed in experimental devices and for designing next‐step machines, the existing NTM theory is imperfect and the use of it is questionable. The main reason for such conclusion is a tangle of problems related to polarization current effect. Analytical approaches in the magnetic island theory are presented.
What really happens with the electron gas in the famous Franck‐Hertz experiment?
Authors: Sigeneger F. , Winkler R. , Robson R. E. 
Published: July 2003

AbstractThe interpretation of the anode current characteristics obtained in the famous Franck‐Hertz experiment of 1914 led to the verification of Bohr's predictions of quantised atomic states. This fundamental experiment has been often repeated, and nowadays is generally part of the curriculum in modern physics education. However, the interpretation of the experiment is typically based upon significant simplifying assumptions, some quite unrealistic. This is the case especially in relation to the kinetics of the electron gas, which is in reality quite complex, due mainly to non‐uniformities in the electric field, caused by a combination of accelerating and retarding components. This non‐uniformity leads to a potential energy valley in which the electrons are trapped. The present state of understanding of such effects, and their influence upon the anode characteristics, is quite unsatisfactory. In this article a rigorous study of a cylindrical Franck‐Hertz experiment is presented, using mercury vapour, the aim being to reveal and explain what really happens with the electrons under realistic experimental conditions. In particular, the anode current characteristics are investigated over a range of mercury vapour pressures appropriate to the experiment to clearly elaborate the effects of elastic collisions (ignored in typical discussions) on the power budget, and the trapping of electrons in the potential energy valley.
Polar recombination as the main process explaining the M‐effect
Authors: Musa G. , Baltog A. 
Published: July 2003

AbstractA full explanation of the M‐effect, namely the reduction of the neon emission spectra practically to only one line of wavelength λ1 = 585.3 nm, when the filling gas is a mixture Ne + Ar + H2 or Ne + Xe + H2 is presented. The M‐effect is explained by ion‐ion recombination according to the reaction Ne+ H– = Ne*(2p1)+H, which feeds selectively the level 2p1 of neon. All observed behavior of the M‐effect is explained by polar recombination. Extension of the M‐effect to other gas mixtures containing at least one electronegative component is also underlined.
Synthesis and Structures of Compounds Based on Chalcocyanide Tetranuclear Rhenium Clusters: Bonding Cluster Complexes by diene‐Bridged CuII Units
Authors: Mironov Yuri V. , Efremova Olga A. , Naumov Dmitry Yu. , Sheldrick William S. , Fedorov Vladimir E. 
Published: July 2003

AbstractSix new tetrahedral chalcocyanide cluster compounds, [{Cu2(dien)3}Re4S4(CN)12] (1), [{Cu(dien)(NH3)}2Re4Se4(CN)12]·2.5H2O (2), [{Cu2(dien)3}Re4Q4(CN)12]·nH2O (Q = Se (3), Te (4)] and [K(H2O)2]2[{Cu3(dien)4}{Re4Q4(CN)12}2]·8H2O where Q = Se (5), Te (6) (dien = diethylenetriamine), have been synthesized by treating aqueous solutions of the salt‐like cluster compounds K4Re4Q4(CN)12·nH2O with solutions of copper(II) chloride in aqueous ammonia containing diethylenetriamine. All six compounds have been characterized by single‐crystal X‐ray diffraction analysis. Compound 1 has a chain‐like polymeric structure; orthorhombic, space group Pmn21. Compound 2 has a molecular structure; triclinic, space group P
. Compounds 3 and 4 are isostructural and also exhibit molecular structures; monoclinic, space group P21/n. Compounds 5 and 6 are isostructural and display a cross‐bridged chain‐like polymeric structure; triclinic, space group P
. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Mono‐Dithiolene Molybdenum(IV) Complexes of cis‐1,2‐Dicyano‐1,2‐ethylenedithiolate (mnt2−): New Models for Molybdenum Enzymes
Authors: Sugimoto Hideki , Siren Kazushi , Tsukube Hiroshi , Tanaka Koji 
Published: July 2003

AbstractNew mono‐dithiolene molybdenum(IV) complexes of cis‐1,2‐dicyano‐1,2‐ethylenedithiolato [(mnt)2−] have been synthesized as models for molybdenum enzymes, with 4,4′‐di‐tert‐butyl‐2,2′‐bipyridine (Bu2bpy) and, N,N′‐tetraethylethylenediamine (Et4en) as ancillary ligands, and characterized by IR, UV/Vis, elemental analysis, ESI‐mass and electrochemical techniques. The temperature‐dependent 1H NMR spectra, recorded in CD3CN solution, indicated that [MoO(mnt)(Bu2bpy)] (1) has a rigid structure but [MoO(mnt)(Et4en)] (2) showed dynamic conformational inversion processes involving the chelating ethylenediamine unit. The complexes exhibited different reactivities toward molecular oxygen: 1 gave a single oxo‐bridged dimolybdenum dimer complex [Mo2O3(mnt)2(Bu2bpy)2] (3), while 2 did not react with O2 and kept its mononuclear structure. Both complexes have almost the same redox potential for MoIV/V, and so the steric bulkiness and conformational dynamics were thought to cause this marked contrast. The obtained dimolybdenum complex 3 was also structurally characterized and investigated, and found to be a new dimolybdenum complex with one dithiolene per molybdenum. The crystal structure of the starting complex 4 was also reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
New 1,3,4‐Oxadiazolecopper(II) Derivatives Obtained from Thiosemicarbazone Complexes
Authors: Gómez‐Saiz Patricia , García‐Tojal Javier , Maestro Miguel A. , Mahía José , Arnaiz Francisco J. , Lezama Luis , Rojo Teófilo 
Published: July 2003

AbstractPyridine‐2‐carbaldehyde thiosemicarbazone and pyridine‐2‐carbaldehyde 4N‐methyl thiosemicarbazone ligands (HLI and HLImm respectively) undergo an oxidative cyclization when treated with bromate or iodate, leading to 2‐amino‐5‐pyridin‐2‐yl‐1,3,4‐oxadiazole and 2‐methylamino‐5‐pyridin‐2‐yl‐1,3,4‐oxadiazole (HLII and HLIImm). This reaction occurs either with free ligands or when coordinated to copper(II). Some of the starting ([{Cu(LImm)(NO3)}2] (3), intermediate Cu(LI)(IO3)·(H2O) (1), [{Cu(LI)I}2] (2), [{Cu(LImm)Br}2] (4), and final compounds [{Cu(HLII)(H2O)3}2](SO4)2 (5), [{Cu(HLIImm)(H2O)2(SO4)}2]·2H2O (6), (HLII) (7), [HLIImm]·3H2O (8) have been isolated and characterized by elemental analyses, IR, UV‐visible, NMR, and EPR spectroscopy. The structures of 2, 3, 4, 5, 6, and 8, solved by X‐ray diffraction methods, contain dinuclear entities with either square‐pyramidal (2, 3, 4) or octahedral (5, 6) copper(II) ions. Structural and spectroscopic results suggest that ligand‐to‐metal charge transfer occurs in these compounds. The EPR spectra at 120 K exhibit rhombic (1, 3, 4), isotropic (2), and axial (5, 6) signals. Magnetic measurements show antiferromagnetic couplings for 2, 4, 5, and 6. The susceptibility data were fitted by the Bleaney−Bowers equation for copper(II) dimers. The obtained J/k values are −20.20, −8.85, −2.75, and −2.78 K for 2, 4, 5, and 6, respectively. However, ferromagnetic intradimeric interactions are present in 3 (J/k = +9.90 K) together with antiferromagnetic interdimer coupling (z′J′/k = −1.70 K). Magneto‐structural studies show the influence of the non‐thiosemicarbazone coligand in the magnetic behaviour of these complexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Syntheses, Reactivity Studies and the Catalytic Properties of a Series of Tetraosmium−Gold Mixed‐Metal Clusters
Authors: Li Yat , Wong Wing‐Tak 
Published: July 2003

AbstractTreatment of the mixture of [Os4(μ‐H)4(CO)12] and [AuPPh3Cl] with excess triethylamine afforded three novel tetraosmium−gold mixed‐metal clusters, [Os4Au2(μ‐H)2(CO)11(PPh3)3] (4), [Os4Au3(μ‐H)3(CO)11(PPh3)3] (5), and [Os4Au4(μ‐H)2(CO)11(PPh3)4] (6) in moderate yields. Cluster [Os4Au(μ‐H)3(CO)11(NMe3)(PPh3)] (2) was also obtained in a similar reaction in the presence of trimethylamineN‐oxide. They were fully characterized by different spectroscopic techniques, and the solid‐state structures were established by X‐ray analysis. These dimetallic clusters exhibit an osmium/gold ratio ranging from 1 to 4. Their electronic absorption properties, electrochemistry, and catalytic properties, as a result of the oxidative carbonylation of aniline, were investigated in terms of the Os/Au ratio. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Coordination of Actinide Ions in Wells−Dawson Heteropolyoxoanion Complexes
Authors: Chiang Ming‐Hsi , Williams Clayton W. , Soderholm L. , Antonio Mark R. 
Published: July 2003

AbstractAlthough many low‐valent (III, IV) actinide (An) ions are known to form coordination complexes with the α‐2 isomer of the lacunary Wells−Dawson polyoxoanion, [P2W17O61]10−, there is little structural information about the An−O interactions, particularly in solution. We have probed the An−O coordination environment for the series of clusters [An(α‐2‐P2W17O61)2]n− with An4+ (Th4+, U4+, Np4+, Pu4+) and An3+ (Np3+, Pu3+, Am3+) in both solution and solid phases using X‐ray absorption fine structure (XAFS). Comparisons are made with the lanthanide (Ln) coordination environments in the series of 4f‐ion clusters, [Lnn+(α‐2‐P2W17O61)2]n−20, and with the related monovacant Lindqvist anions, [Lnn+(W5O18)2]n−12, for n = 3, 4. The average An−O8 and Ln−O8 distances correlate with their cationic VIII‐coordinate ionic radii, indicating that the An and Ln ions have indistinguishable coordination behavior. Metrical details are consistent with simple charge and size considerations for both trivalent and tetravalent An ions as well as Ln ions coordinated with α‐2‐[P2W17O61]10− and [W5O18]6−. This result is contrasted to trends established for these f‐ions coordinated to the Preyssler anion [Lnn+P5W30O110]n−15. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Three Novel Polymeric Frameworks Assembled from CdII, CoII, and MnII with the Mixed Organic Ligands 3,4‐Pyridinedicarboxylate, 1,3‐Bis(4‐pyridyl)propane, or 1,2‐Bis(4‐pyridyl)ethane
Authors: Fu Zhi‐Yong , Hu Sheng‐Min , Dai Jing‐Cao , Zhang Jian‐Jun , Wu Xin‐Tao 
Published: July 2003

AbstractHydrothermal reactions of CdII, CoII, and MnII with the mixed ligands 3,4‐pyridinedicarboxylate (pydc), 1,3‐bis(4‐pyridyl)propane (bpp), or 1,2‐bis(4‐pyridyl)ethane (bpe) gave crystals of {[Cd(pydc)(bpp)]·0.5H2O}n (1), {[Co(pydc)(H2O)(bpe)0.5]·0.5H2O}n (2), and {[Mn(pydc)(H2O)(bpe)0.5]· 0.5H2O}n (3), respectively. Single‐crystal X‐ray analyses reveal that these are all three‐dimensional non‐interpenetrating coordination polymers. Their structures alter markedly with the conformation and the function of the ligands. In 1, the 3,4‐pyridinedicarboxylate acted as a three‐connector, a coordination topology of the type (3,5) [containing 3 and 5 connected centers] being generated through self‐assembly, while in 2 and 3, with the help of the four‐connector 3,4‐pyridinedicarboxylate and the terminal ligand water molecule, another three‐dimensional framework with a coordination topology of the type (4, 5) was obtained. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis and Molecular Structures of Nickel(II) and Cobalt(III) Complexes with 2‐(Arylimino)‐3‐(hydroxyimino)butane
Authors: Zangrando Ennio , Trani Manuela , Stabon Elisa , Carfagna Carla , Milani Barbara , Mestroni Giovanni 
Published: July 2003

AbstractWe report new series of NiII and CoIII complexes with nitrogen‐donor chelating ligands of the (E,E)‐2‐(arylimino)‐3‐(hydroxyimino)butane type (Ar−N∩N−OH). These ligands are characterized by a hydrophilic (OH group) and a hydrophobic region (aryl group). NiII derivatives were obtained either as trimers of formula [Ni3(Ar−N∩N−OH)3Br4(OH)][Br], with the hydrophobic groups oriented on the same side, or as bis(chelated) derivatives with cis geometry, depending on the steric hindrance of the aryl groups. CoIII complexes were obtained only as bis(chelated) derivatives, with the two ligands coplanar. The “iso‐oriented” arrangement of ligands in bis(chelated) CoIII complexes is favored by weak interactions between the two ligands, namely O−H···O hydrogen bond and stacking interactions between the aryl groups. CoIII complexes might find application as catalysts for living or controlled radical polymerization of polar olefins, and preliminary results are reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
NMR Investigation and Dynamic Behaviour of [2,2′‐Bipyridylbis(pyridine)platinum(II)]2+ and Related Cationic Complexes − Crystal Structure of [Pt(bipy)(py)2](PF6)2
Authors: Rotondo Enrico , Bruschetta Giuseppe , Bruno Giuseppe , Rotondo Archimede , Di Pietro Maria Letizia , Cusumano Matteo 
Published: July 2003

AbstractDetailed 1H and 13C{1H} NMR analysis has been carried out on complexes with the general formulae [Pt(bipy)(n‐Rpy)2](PF6)2 and [Pt(4‐Phbipy)(n‐Rpy)2](PF6)2 [bipy = 2,2′‐bipyridyl; 4‐Phbipy = 4,4′‐diphenyl‐2,2′‐dipyridyl; n‐Rpy = pyridine or substituted pyridines]. The resonance assignments and X‐ray structures of these complexes are important steps on our route to: (i) interpretation of the intercalative geometry on the basis of the magnetic changes produced on interaction with DNA, (ii) rational design of new intercalators. The X‐ray structure of the parent complex [Pt(bipy)(py)2](PF6)2 (py = pyridine) shows pyridine rings quasiperpendicular to the coordination plane. In solution, because of the hindered rotation about Pt−N bonds of ortho‐ and meta‐monosubstituted pyridines, this arrangement leads to “head‐to‐head” s‐cis Cs and “head‐to‐tail” s‐trans C2 rotamers in equilibrium. NMR line shape and 13C relaxation time constant measurements were carried out in order to evaluate activation energies and anisotropic rotational motion of n‐Rpy. In some of these complexes a second dynamic process could be frozen on the 13C NMR timescale below 265 K. This lower activation energy process can reasonably be attributed to minimal bipyridyl torsion angle flipping driving a concerted molecular motion about the core of the four N‐donors. Indeed, the X‐ray structure of 1 proves distortion with a slight alternate up and down shift of the four nitrogen atoms about the coordination plane. Significantly, the fast rotation of unhindered pyridine rings does not allow NMR detection of this molecular distortion. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Bis(2‐aminobutanol)dichloroplatinum(II) Complexes and Their Singly and Doubly Ring‐Closed Butanolato Species − Novel Prodrugs for Platinum‐Based Antitumour Chemotherapy?
Authors: Galanski Mathea Sophia , Baumgartner Christian , Arion Vladimir , Keppler Bernhard K. 
Published: July 2003

AbstractCytotoxic hydroxyethyl‐substituted (amine)platinum(II) and ‐(IV) complexes have recently attracted attention because of the ability of their hydroxyethyl groups to coordinate through the oxygen atom to the platinum centre during oxidation with hydrogen peroxide or through intramolecular ligand exchange reactions in dichloroplatinum(II) complexes. The last point in particular is of great interest, because the intramolecular attack of the hydroxy group dramatically influences the mode of action of platinum(II) compounds. On the other hand, there is also the chance to use such reactions specifically for the synthesis of novel anticancer platinum‐based drugs for chemotherapy. We have therefore focused our chemistry program on the synthesis of dichloroplatinum(II) complexes that are in a position to form singly and, especially, doubly ring‐closed alcoholato species and on investigation of their structures by X‐ray crystallography. It was possible to determine the crystal structures of [Pt{(R)‐(−)‐HL}2Cl2], [Pt{(S)‐(+)‐HL}2Cl2], [Pt{(R)‐(−)‐HL}{(S)‐(+)‐HL}Cl2], [Pt{(S)‐(+)‐HL}{(S)‐(+)‐L}Cl], [Pt{(R)‐(−)‐L}2] and [Pt{(S)‐(+)‐L}2] (HL = 2‐aminobutanol‐κN, L = 2‐aminobutanolato‐κ2N,O). The results obtained may represent the first step towards novel prodrugs for platinum‐based antitumour chemotherapy. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Rhodium and Ruthenium Complexes of 1,1′‐Bis(phosphetano)ferrocenes: Structural Characterisation and Catalytic Behaviour
Authors: Marinetti Angela , Labrue Francis , Pons Bénédicte , Jus Sébastien , Ricard Louis , Genêt Jean‐Pierre 
Published: July 2003

AbstractThe first structural characterisation of ruthenium and rhodium complexes of the 1,1′‐bis(phosphetano)ferrocenes 1 (FerroTANEs) − namely [{(S,S)‐iPr‐1}RuCl2Py2] and [{(S,S)‐iPr‐1}Rh(COD)OTf] − is reported. X‐ray data show that the ruthenium complex and the rhodium chelate complex both adopt δ conformations, as a result of the (S,S) configuration of the phosphetane moiety. The ruthenium complexes promote the catalytic hydrogenation of β‐keto esters with moderate to high enantioselectivities. The behaviour of the rhodium complexes of 1 is compared with that of other phosphetane‐based catalysts in the hydrogenation of methyl N‐acetamidocinnamate. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Reactions of Dihydrogen(norbornadiene) Complexes
Authors: Jia Guochen , Lin Zhenyang , Lau Chak Po 
Published: July 2003

AbstractDihydrogen(olefin) complexes have been proposed as active species in catalytic hydrogenation reactions. We have studied the hydrogen‐transfer reactions of dihydrogen(olefin) complexes, especially those containing the norbornadiene (NBD) ligand, in order to address the following questions: (i) how the alignment of a H2 ligand relative to an olefin ligand may affect their reactivity; (ii) in general, what is the detailed pathway for intramolecular hydrogen transfer from an H2 ligand to an olefin ligand; and (iii) how will the hydrogen transfer reactions proceed in the presence of both an H2 and a hydride ligand. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Two‐ and Three‐Dimensional Frameworks Constructed From Bicapped Keggin Clusters
Authors: Duan Li‐Mei , Pan Cheng‐Ling , Xu Ji‐Qing , Cui Xiao‐Bing , Xie Feng‐Tong , Wang Tie‐Gang 
Published: July 2003

AbstractThe novel two‐ and three‐dimensional solid materials [Cu(en)2(H2O)]{PMoVI8VIV6O42[Cu(en)2][Cu0.5(en)]3}·5.5H2O and H3{VVMoVI8VIV6O42[Cu(en)2]4}[MoO4]2·14H2O (en = ethylenediamine) have been hydrothermally assembled and structurally characterized. Both networks are based on mixed Mo/V bicapped Keggin clusters interconnected through the transition metal complex moieties. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Diorganotin(IV) Complexes of a Cyclic Thiosemicarbazone Ligand: Crystal Structures of [SnPh2(C15H10N3S)Cl] and [SnMe2(C15H10N3S)2]
Authors: López‐Torres Elena , Mendiola M. Antonia , Pastor César J. , Procopio Jesús R. 
Published: July 2003

AbstractTreatment of 5‐methoxy‐5,6‐diphenyl‐4,5‐dihydro‐2H‐[1,2,4]triazine‐3‐thione (LH2OCH3) with compounds SnR2X2 (R = Me and Ph; X = Cl and NO3) afforded, for the first time, metal derivatives of a cyclic thiosemicarbazone. Treatment of LH2OCH3 with the appropriate diorganotin(IV) chloride in dichloromethane provided 1:1 complexes, but 1:2 derivatives were isolated when the nitrate salts in distilled water were used. The complexes were studied by mass spectrometry, IR and multinuclear (1H, 13C and 119Sn) NMR in solution, and also by 119Sn CP/MAS NMR spectroscopy and by X‐ray diffraction in the solid state. In all the complexes, the thiosemicarbazone had been modified by formation of a new C=N bond. In addition, the ligand LH had lost a hydrogen atom, acting as an anion. The crystal structures of [SnPh2(C15H10N3S)Cl] (1) and [SnMe2(C15H10N3S)2] (4) each consist of discrete molecules with the tin atom bonded to the sulfur and amine nitrogen atoms to give a four‐membered chelate ring with the [1,2,4]triazine modified. For phenyl derivative 1, the tin atom is in a trigonal‐bipyramidal environment with the phenyl rings in equatorial positions, and for complex 4 it is in an octahedral arrangement, with the methyl groups in axial positions. The 119Sn CP/MAS NMR spectra of the complexes are in accordance with these structures. The values obtained indicate a five‐coordinate geometry for [SnMe2(C15H10N3S)Cl] (2) and suggest a coordination number of six for complex 3. The 119Sn spectra of complexes in solution depend on the coordinating capacity of the solvents. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis and Reactivity of Alkylzirconium Complexes Incorporating Asymmetrically Substituted ansa Ligands − X‐ray Crystal Structure of [Zr{Me2Si(η5‐C5Me4)(η5‐C5H3Me)}(CH2Ph)Cl]
Authors: Antiñolo Antonio , Fernández‐Galán Rafael , Gallego Beatriz , Otero Antonio , Prashar Sanjiv , Rodríguez Ana M. 
Published: July 2003

AbstractThe monoalkyl complexes [Zr{Me2Si(η5‐C5Me4)(η5‐C5H3R)}(R′)Cl] [R = Me, R′ = CH2Ph (1); R = Me, R′ = CH2SiMe3 (2); R = iPr, R′ = CH2Ph (3); R = iPr, R′ = CH2SiMe3 (4); R = SiMe3, R′ = CH2Ph (5); R = SiMe3, R′ = CH2SiMe3 (6)] have been synthesized by the reaction of the corresponding ansa‐metallocene dichloride complex and 1 equiv of the alkyl Grignard reagent. Dialkyl complexes with large alkyl groups only formed for the zirconocene complex containing the ansa ligand Me2Si(η5‐C5Me4)(η5‐C5H4) and with the benzyl substituent giving [Zr{Me2Si(η5‐C5Me4)(η5‐C5H4)}(CH2Ph)2] (7). When the alkyl substituent is CH2SiMe3 only the monoalkyl derivative, [Zr{Me2Si(η5‐C5Me4)(η5‐C5H4)}(CH2SiMe3)Cl] (8), was formed. The insertion reaction of the isocyanide reagent CNC6H3Me2‐2,6 into the zirconium−carbon σ‐bond of complexes 1−8 gave the corresponding η2‐iminoacyl compound [Zr{Me2Si(η5‐C5Me4)(η5‐C5H3R)}{η2‐R′C=NC6H3Me2‐2,6}Cl] [R = Me, R′ = CH2Ph (9); R = Me, R′ = CH2SiMe3 (10); R = iPr, R′ = CH2Ph (11); R = iPr, R′ = CH2SiMe3 (12); R = SiMe3, R′ = CH2Ph (13); R = SiMe3, R′ = CH2SiMe3 (14); R = H, R′ = CH2SiMe3 (16)] and [Zr{Me2Si(η5‐C5Me4)(η5‐C5H4)}{η2‐PhCH2C=NC6H3Me2‐2,6}(CH2Ph)] (15). The molecular structure of 1 has been determined by single‐crystal X‐ray diffraction studies. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
A Novel One‐Dimensional Chain Complex Composed of Oxo‐Centered Trinuclear Manganese Clusters
Authors: Kim Jinkwon , Lim Jin Mook , Do Youngkyu 
Published: July 2003

AbstractA new linear chain complex of oxo‐centered trinuclear manganese clusters, [{MnIII2MnIIO(O2CCHCl2)6(H2O)}{Mn(O2CCHCl2)2(H2O)4}]n (1), has been synthesized by treatment of a mixture of Mn(OAc)2·4H2O and dichloroacetic acid in dichloromethane with KMnO4. In this complex chains are formed by hydrogen bonding between carboxylate oxygens and coordinated water molecules, forming a two‐dimensional structure. Antiferromagnetic coupling was observed by variable‐temperature magnetic measurements. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)