bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigations on 1‐Metallaindanes
Authors: Goedheijt Marcel Schreuder , Nijbacker Tom , Horton Andrew D. , Kanter Franciscus J. J. de , Akkerman Otto S. , Bickelhaupt Friedrich 
Published: February 2003

Abstract1‐Mercuraindane (6) was prepared in three steps from 1‐bromo‐2‐(2‐bromoethyl)benzene (3) and converted into 1‐magnesaindane (1) by reaction with magnesium. In solution,6was observed to occur in a remarkable dimer/trimer equilibrium, whereas1forms a dimer. From1and dichlorozirconocene, the 1‐zirconaindane2was obtained, which reacted with B(C6F5)3to form the adduct13. According to spectroscopic data,13is formed by attack of the β‐methylene carbon atom at the boron atom and has a zwitterionic structure with weak interactions between the zirconium ion and one of theortho‐fluorine atoms. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
A Complex‐Based Soft Template Route to PbSe Nanowires
Authors: Liu Yuanfang , Cao Jinbo , Zeng Jinghui , Li Cun , Qian Yitai , Zhang Shuyuan 
Published: February 2003

AbstractPbSe nanowires with an average size of 8 × 350 nm were synthesized by the reaction of Pb(NO3)2 and Se powder at 60 °C under ambient pressure. A mixture of arachidic acid (AA, n‐C19H39COOH) and octadecylamine (ODA), which could form a complex with Pb2+, was employed as a soft template to control the morphology of the resultant PbSe nanowires. The products were characterized by X‐ray powder diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and transmission electron microscopy. The photoluminescence (PL) spectrum of the PbSe nanowires is presented. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Cobalt Chloride Complexes of N3 and N4 Donor Ligands
Authors: Kooistra T. Martijn , Hekking Koen F. W. , Knijnenburg Quinten , de Bruin Bas , Budzelaar Peter H. M. , de Gelder René , Smits Jan M. M. , Gal Anton W. 
Published: February 2003

AbstractA number of cobalt(II) chloride complexes of pyridine/amine N3 and N4 donors have been prepared and structurally characterised. Even though they are paramagnetic, assignment of the 1H NMR signals was possible in several cases. With the exception of tpa, which formed a cationic monochloride complex, all new complexes have cis‐coordinated chlorides. Nevertheless, only the relatively rigid pyp ligands gave rise to (low) ethene polymerisation activity on activation with MAO. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Reactions of cis‐2,3‐Dimethylaziridine, 3‐Pyrroline and Pyrrolidine with Me3Al and Me3Ga: Adducts and Dimeric Amides
Authors: Zhang Yuankui , Budzelaar Peter H. M. , Smits Jan M. M. , Gelder René de , Hageman Paul R. , Gal Anton W. 
Published: February 2003

AbstractThe reactions of Me3Al and Me3Ga with cis‐2,3‐dimethylaziridine (1‐H), 3‐pyrroline (2‐H) and pyrrolidine (3‐H) have been investigated. At room temperature, monomeric adducts [Me3M·LH] are obtained (M = Al, Ga; L = 1−3). [Me3Al·1‐H] is the first example of a structurally characterized adduct of an aziridine and a group 13 metal. On heating in mesitylene, all adducts except [Me3Ga·2‐H] evolve methane to form the corresponding amides; the Ga complexes require somewhat higher temperatures for this reaction. In contrast to the unsubstituted aziridine derivatives (which are trimers), dimethylaziridine amides Me2M‐1 are dimers, as shown by X‐ray crystallography. NMR spectroscopic data suggest the occurrence of a cis‐trans equilibrium for these dimers in solution. For the pyrroline and pyrrolidine derivatives, the X‐ray structures suggested large changes in the C−C and C−N bond lengths on formation of the adducts and amides. However, DFT calculations reveal that these changes are artefacts, and that the real bond length changes are fairly modest. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis and Structures of Alkaline‐Earth Metal Supersilanides: tBu3SiMX and tBu3Si−M−SitBu3 (M = Be, Mg; X = Cl, Br)
Authors: Lerner Hans‐Wolfram , Scholz Stefan , Bolte Michael , Wiberg Nils , Nöth Heinrich , Krossing Ingo 
Published: February 2003

AbstractThe alkaline‐earth metal silanides, (tBu3Si)2Be and (tBu3Si)2Mg, have been synthesized from the reaction of the sodium silanide tBu3SiNa with BeCl2 in Bu2O and MgBr2 in THF. The bissupersilylmagnesium THF adduct [(tBu3Si)2Mg(THF)2] reacts with GaBr3 in benzene at ambient temperature to form tBu3SiGaBr2 and tBu3SiMgBr(THF). The structures of bissupersilyl silanides, (tBu3Si)2Be and (tBu3Si)2Mg(THF)2, and the Grignard analogue, tBu3SiMgBr(THF), have been determined by X‐ray structure analysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
The Chelating Ligand 1,3‐Bis(pyrazol‐1′‐yl)propane (Bpp) Enforces a Tetrahedral Geometry in Both CuII and CuI Species
Authors: Flinzner Kristel , Stassen Arno F. , Mills Allison M. , Spek Anthony L. , Haasnoot Jaap G. , Reedijk Jan 
Published: February 2003

AbstractThe ligand 1,3‐bis(pyrazol‐1′‐yl)propane (bpp) has been prepared by reacting 1,3‐dichloropropane with two equivalents of pyrazole. After reaction of bpp with copper(II) tetrafluoroborate, three different compounds were obtained, two with CuII and one with CuI as cation, depending on the preparative method. The formation of single crystals of these compounds was only observed when 1‐(3‐chloropropyl)pyrazole (ppc) was present in the solution. The single‐crystal X‐ray structures of [Cu(bpp)2](BF4)2 and [Cu(bpp)2](BF4) show that bpp acts as a didentate chelating ligand to form an uncommon eight‐atom chelate ring with the copper ion. Two polymorphs of the CuII complex were characterized. In each of them, the metal atoms possess a distorted tetrahedral geometry. In the copper(I) complex the metal center is present in a less‐distorted tetrahedral coordination sphere. The spectroscopic properties of the compounds are in agreement with the structural data. Cyclic voltammetry measurements showed a redox wave at 0.92 V vs. Ag/AgCl. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis and X‐ray Structures of Tin(IV) and Lead(II) Complexes with Heterocyclic Thiones
Authors: Sousa‐Pedrares Antonio , Casanova María I. , García‐Vázquez José A. , Durán María L. , Romero Jaime , Sousa Antonio , Silver Jack , Titler Philip J. 
Published: February 2003

AbstractTin(IV) and lead(II) complexes of 3‐(trifluoromethyl)pyridine‐2‐thione (3‐CF3‐pySH) and 5‐(trifluoromethyl)pyridine‐2‐thione (5‐CF3‐pySH) have been synthesised. The compounds [Sn(3‐CF3‐pyS)4] (1), [Sn(5‐CF3‐pyS)4] (2), [Pb(3‐CF3‐pyS)2] (3), and [Pb(5‐CF3‐pyS)2] (4) were obtained by addition of the appropriate ligand to a methanol solution of tin(II) chloride or lead acetate in the presence of triethylamine. The complex [Sn(5‐CF3‐pyS)4] was also prepared by electrochemical oxidation of a tin anode in a cell containing an acetonitrile solution of the ligand 5‐(trifluoromethyl)pyridine‐2‐thione. The X‐ray crystal structure of [Sn(3‐CF3‐pyS)4] reveals a dodecahedral coordination geometry around SnIV, with the four thionate ligands acting in a bidentate (N,S) manner. [Sn(5‐CF3‐pyS)4] also consists of monomeric neutral molecules with the tin(IV) atom in an octahedral geometry with two bidentate (N,S) ligands and two monodentate S ligands. The molecular structure of [Pb(3‐CF3‐pyS)2] shows the metal in a five‐coordinate geometry with the stereochemically active lead(II) lone pair in an equatorial position of a trigonal bipyramid. Spectroscopic data for the complexes (IR, NMR, FAB, and Mössbauer spectra) are discussed and related to the structural information. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis and Reactivity of the First η6‐Rhodium(I) and η6‐Iridium(I) Complexes of 2,6‐Bis(trimethylsilyl)phosphinines
Authors: Doux Marjolaine , Ricard Louis , Mathey François , Floch Pascal Le , Mézailles Nicolas 
Published: February 2003

AbstractIt has been shown that 2 equiv. of 2,3,5,6‐tetraphenylphosphinine (2) react with [Rh(COD)2][BF4] to yield the bis(η1‐phosphinine)RhI complex 6, whose X‐ray crystal structure is presented. On the other hand, 2,6‐bis(trimethylsilyl)phosphinines 4 and 5 react with Rh+ and Ir+ precursors to yield the first (η6‐phosphinine)RhI and ‐IrI complexes 7−10, and 11−12, respectively. The X‐ray crystal structure of complex 8 is presented. Reaction of these η6‐phosphinine complexes with water or ethanol yields the first (η5‐phosphacyclohexadienyl)RhI and ‐IrI complexes 13−17, resulting from the formal 1,1‐addition of RO− and H+. DFT calculations comparing isoelectronic (η6‐phosphinine)‐ and (η6‐benzene)Fe0 and ‐RhI complexes allows the rationalization of the large difference in reactivity of these complexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Electrospray Behavior of Lacunary Keggin‐Type Polyoxotungstates [XW11O39]p− (X = Si, P): Mass Spectrometric Evidence for a Concentration‐Dependent Incorporation of an MOn+ (M = WVI, MoVI, VV) Unit into the Polyoxometalate Vacancy
Authors: Bonchio Marcella , Bortolini Olga , Conte Valeria , Sartorel Andrea 
Published: February 2003

AbstractESI‐MS analysis provides a straightforward tool for the solution characterization of highly charged mono‐lacunary Keggin‐type polyoxotungstates α‐[XW11O39]p− (X = Si, P; p = 8, 7). Doubly and triply charged quasi‐molecular ion peaks were identified on the basis of both the theoretical simulation of the isotopic cluster distributions and the fragmentation modes observed with MS/MS technique. This approach allows the characterization of the inorganic polyanions transferred into the gas‐phase with associated alkali metal cations (Li+, Na+). Indeed, the ESI‐MS spectrum was found to be dependent on the counterion nature and on the initial concentration of the polyoxotungstate. While lithium salts at millimolar concentration represent the best choice for the analytical protocol, upon dilution the inorganic structure rearranges to a saturated Keggin dodecametalate complex. This phenomenon is induced by the electrospray ionization process and was exploited to produce gas‐phase ions of monosubstituted species formed through incorporation of molybdenum and vanadium into the polyoxotungstate framework. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis and Structure of Redox‐Active Heterotetranuclear Molecular Polygons by Self‐Assembly of Two Ferrocene‐Bridged Bis(pyridines) with Two Transition Metals
Authors: Lindner Ekkehard , Zong Ruifa , Eichele Klaus , Weisser Ulrike , Ströbele Markus 
Published: February 2003

AbstractThe macrocyclic complexes [(η5‐C5H4C2‐4‐py)2Fe]2Ni2(NO3)4 (2), [(η5‐C5H4C2‐3‐py)2Fe]2Ag2(ClO4)2 (4), and [(η5‐C5H4C2‐3‐py)2Fe]2Pd2Cl4 (5) were obtained by reaction of [Ni(H2O)6](NO3)2, AgClO4, and PdCl2(COD) with the ligands (η5‐C5H4C2‐4‐py)2Fe (1) and (η5‐C5H4C2‐3‐py)2Fe (3), respectively, under high dilution conditions (Scheme 1). The molecular motifs of 2, 4, and 5 were studied by single‐crystal X‐ray structural investigations. Elemental analyses and 1H NMR and IR spectra were also used to confirm the structures. Compound 2 represents an unsymmetric paddlewheel, in which the centers of the four Cp rings define a nearly ideal rectangle with dimensions of 20.2 × 3.3 Å. In principle, macrocycles 4 and 5 can also be described as rectangles, however, due to the 3‐positioned nitrogen donors with deformed edges (17.4 × 3.3 Å for 4). In contrast to the offset packing of the molecules in 2, the macrocycles in the crystal of 4 are aligned, with trapped acetonitrile molecules in between. The intra‐ and intermolecular Ag−Ag distances are 3.50 and 3.79 Å, respectively. Cyclovoltammetric studies reveal chemically reversible ferrocene‐based redox reactions of 1−4. Although no electronic communication was observed between the two identical ferrocene units, a weak through‐bond electronic interaction between ferrocene and nickel, or silver, was established. In 2 a weak antiferromagnetic interaction between the nickel atoms was also found. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Orientation‐ and Temperature‐Dependent Rotational Behavior of Imidazole Ligands (L) in β‐[Ru(azpy)2(L)2](PF6)2 Complexes
Authors: Velders Aldrik H. , Quiroga Adoracion Gomez , Haasnoot Jaap G. , Reedijk Jan 
Published: February 2003

AbstractThe synthesis and characterization of the cis bifunctional coordinated ruthenium(II) complexes β‐[Ru(azpy)2(MeIm)2](PF6)2 (β‐MeIm) and β‐[Ru(azpy)2(MeBim)2](PF6)2 (β‐MeBim) (azpy = 2‐phenylazopyridine, MeIm = 1‐methylimidazole and MeBim = 1‐methylbenzimidazole) is reported. In β‐MeIm the two MeIm ligands can both freely rotate around the Ru−N axes on the NMR timescale. In β‐MeBim the two MeBim ligands appear restricted in their rotation around the Ru−N axes, which becomes slow on the NMR timescale at low temperatures. In contrast to the analogous complexes α‐[Ru(azpy)2(MeBim)2](PF6)2 and cis‐[Ru(bpy)2(MeBim)2](PF6)2, only one atropisomer is observed for the two MeBim ligands in β‐MeBim. The orientation of the MeBim ligands appears to correspond to an HT isomer which is similar to the orientation of the MeBim ligands in the most abundant atropisomer found in the related α‐[Ru(azpy)2(MeBim)2](PF6)2. A stacking interaction between the phenyl ring of one azpy and one MeBim ligand is likely to stabilize the observed atropisomer of β‐MeBim, and is such that the rotation of the phenyl ring of one of the two azpy ligands is restricted. At very low temperatures this rotation, or flipping of the phenyl ring between two identical positions, is in the slow‐exchange range on the NMR timescale. (© Wiley‐VCH Verlag GmbH & Co KGaA, 69451 Weinheim, Germany, 2003)
New Molecular Charge‐Transfer Salts of TM‐TTF and BMDT‐TTF with Thiocyanate and Selenocyanate Complex Anions [TMTTF = Tetramethyltetrathiafulvalene; BMDT‐TTF = Bis(methylenedithio)tetrathiafulvalene]
Authors: Mas‐Torrent Marta , Turner Scott S. , Wurst Klaus , Vidal‐Gancedo José , Veciana Jaume , Day Peter , Rovira Concepció 
Published: February 2003

AbstractThree new charge‐transfer salts of tetrathiafulvalene (TTF)‐based donors with thiocyanato‐ or selenocyanato‐metal complex anions have been synthesised. The salts isolated were [BMDT‐TTF]4[Cr(NCS)6] (1), [TM‐TTF]4[Cr(NCS)6]·2CH3CN (2) and [TM‐TTF]4[Cr(NCSe)6]·2CH3CN (3) [BMDT‐TTF = bis(methylenedithio)tetrathiafulvalene and TM‐TTF = tetramethyltetrathiafulvalene]. Single crystals of compound 1 crystallise in the monoclinic C2/c space group with a = 37.286(3), b = 10.0539(6), c = 21.069(2) Å, β = 124.348(4)°, V = 6520.9(9) Å3 and Z = 4. Compound 3 was also suitable for an X‐ray diffraction study, however the anionic part, [Cr(NCSe)6]− was highly disordered and the best solution gave a final R factor of 16.4%. A solution was found for the monoclinic space group C2/m with a = 13.787(3), b = 19.507(3), c = 14.735(5) Å, β = 102.90(3)°, V = 3862.9(17) Å3 and Z = 2. For compound 1 there are several S···S close atomic contacts between the donors and acceptors, but there is no discernible magnetic exchange between ions. Such an interaction was previously observed in related salts such as [TTF][Cr(NCS)4(phenanthroline)2] and [donor][M(NCS)4(isoquinoline)2] [M = Cr, Fe and donor = TTF, BEDT‐TTF or TM‐TTF (tetramethyltetrathiafulvalene)]. Compounds 1 to 3 are all paramagnetic semiconductors in which the magnetic susceptibility is dominated by the Cr‐containing anions. The structure‐function relationship, along with a comparison with related compounds, indicates that there is no long‐range magnetic order because there are no π‐stacking interactions between donor and acceptor; these types of interactions are seen in all of the bulk magnets of this type in which the donor spin is magnetically coupled to the anion. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Syntheses and Structures of Layered Copper(II) Diphosphonates with Mixed Ligands
Authors: Yin Ping , Peng Yang , Zheng Li‐Min , Gao Song , Xin Xin‐Quan 
Published: February 2003

AbstractThis paper describes the syntheses and crystal structures of two new copper(II) diphosphonates with mixed ligands: [Cu3(hedpH)2(4,4′‐bipy)(H2O)2]·2H2O (1) and [Cu3(hedpH)2(4,4′‐azpy)(H2O)2]·1.6H2O (2) (hedp = 1‐hydroxyethylidenediphosphonate, 4,4′‐bipy = 4,4′‐bipyridine, 4,4′‐azpy = 4,4′‐azobispyridine). Both adopt a two‐dimensional layer structure containing neutral ladder‐like chains of {Cu3(hedpH)2(H2O)2}n linked by 4,4′‐bipy or 4,4′‐azpy ligands. The adjacent layers are held together by strong hydrogen bonds, thus generating a three‐dimensional network with rectangular shaped channels. The lattice water is found in these channels. The magnetic properties of compounds 1 and 2 have also been investigated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis, Crystal Structures and Magnetism of a Series of Heptanuclear Rare‐Earth‐Centered Trigonal Prism Clusters
Authors: Liu Qin‐De , Li Jun‐Ran , Gao Song , Ma Bao‐Qing , Kou Hui‐Zhong , Ouyang Liang , Huang Rui‐Li , Zhang Xi‐Xiang , Yu Kai‐Bei 
Published: February 2003

AbstractA series of heptanuclear rare‐earth‐centered trigonal prism clusters [LnCu6(μ‐OH)3(HL)2(L)4]·(ClO4)2·25H2O (Ln = La−Ho and Y; H2L = iminodiacetic acid) was synthesized and their crystal structures were determined by X‐ray diffraction. The rare‐earth center and the copper ions are bridged by three μ3‐OH and six μ2‐O moieties from the carboxyl groups of six different ligands. The rare earth ion is nine‐coordinate and the coordination polyhedron is an unusual, highly symmetrical tricapped trigonal prism (C3h). The cluster has an interesting, highly symmetrical eclipsed structure (C3h) which utilizes the central rare earth cation as a template. The temperature‐dependence of the magnetic susceptibility of the cluster series was investigated and was found to vary with the central rare‐earth ions. The magnitude of the antiferromagnetic interaction constants J between Cu2+ ions in [LaCu6] and [YCu6] were compared and estimated to be −24 cm−1 and −7 cm−1, respectively, indicating a significant effect of the central diamagnetic ions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Spectroscopic and Structural Characterizations of Novel Water‐Soluble Peroxo[polyaminocarboxylato bis(N‐oxido)]niobate(V) Complexes
Authors: Bayot Daisy , Tinant Bernard , Mathieu Benoît , Declercq Jean‐Paul , Devillers Michel 
Published: February 2003

AbstractNew water‐soluble peroxo complexes of niobium(V) with polyaminocarboxylic acids (PAC) have been prepared and characterized by IR and NMR (1H, 13C, 15N) spectroscopy, as well as by thermal analysis. The synthesis in presence of excess H2O2 leads to the oxidation of the nitrogen atoms of the PAC ligand into N‐oxide groups. The compounds obtained correspond to the general formula (AI)3[Nb(O2)2(LO2)]·xH2O·yH2O2 [AI = NH4+ or CN3H6+ (gu) and L = edta, pdta] in which H4LO2 refers to the bis(N‐oxide) derivative of the PAC ligand. The crystal structures of the guanidinium derivatives of the (edta)‐ and (pdta)Nb complexes have been determined, both showing an eight‐coordinate Nb atom with two bidentate peroxo ligands and a quadridentate PAC bis(N‐oxido) ligand, resulting in a distorted dodecahedral geometry. The structure of the guanidinium derivative of the edta bis(N‐oxido) ligand is also described. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Pyridine‐ and 3‐/6‐Methylpyridine‐2‐tellurolate Complexes of Palladium(II) and Platinum(II)
Authors: Dey Sandip , Jain Vimal K. , Singh Jaspreet , Trehan Veena , Bhasin Kuldip K. , Varghese Babu 
Published: February 2003

AbstractThe reaction of py2Te2 or (3‐MeC5H3N)2Te2 with Na2PdCl4 in methanol yields an insoluble brown complex, [PdCl(TeNC5H3R)]n (R = H or Me). Several reactions of pyTe−, (3‐MeC5H3N)Te−, or (6‐MeC5H3N)Te− with various palladium(II) and platinum(II) complexes have been carried out. Complexes of the types [MCl(Te−N)(PR3)], [Pt(Te−N)2(dppe)], [Pt(Te−N)2(PPh3)2], and [Pt2(μ‐Te−N)2(dppe)2][BPh4]2 [M = Pd or Pt; Te−N = pyTe, (3‐ or 6‐MeC5H3N)Te] have been prepared and characterized by elemental analyses, UV/Vis, IR, and NMR (1H, 31P, 195Pt) spectroscopy. The complexes [MCl(Te−N)(PR3)] show irreversible oxidation and reduction by CV in DMF. The molecular structure of [PdCl{Te(3‐MeC5H3N)}(PPh3)] (2c) has been established by single‐crystal X‐ray diffraction analysis. The palladium atom is bound to the chelating 3‐methylpyridinetellurolate ligand, a chlorine atom and a PPh3 ligand. The pyrolysis of [PdCl{Te(3‐MeC5H3N)}(PR3)] (PR3 = PEt3 or PPh3) at 340 °C yields PdTe. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Selective Synthesis of N‐Methylanilinooligosilanes
Authors: Böhme Uwe , Günther Betty , Rittmeister Ben 
Published: February 2003

AbstractDefined crystalline amino‐substituted organosilanes were prepared by reaction of N‐methylaniline with 1,1,2,2‐tetrachloro‐1,2‐dimethyldisilane. It is possible to selectively prepare mono‐, di‐, and triaminodisilanes depending on the reactant ratio. The X‐ray structure analyses of 1,2‐dichloro‐1,2‐dimethyl‐1,2‐bis(N‐methylanilino)disilane (2), 1‐chloro‐1,2‐dimethyl‐1,2,2‐tris(N‐methylanilino)disilane (3), and 1,2‐dimethyl‐1,1,2,2‐tetrakis(N‐methylanilino)disilane (4) were performed. The absolute structure of 2 was determined by crystallographic methods. Compound 2 is a useful reagent for preparing a variety of other aminoorganodisilanes like [Me(PhMeN)2Si]2 (4), [FMe(PhMeN)Si]2 (12), [(PhCC)Me(PhMeN)Si]2 (13), [(p‐MeC6H4)Me(PhMeN)Si]2 (14), and [(PhCH2)Me(PhMeN)Si]2 (15). Other chloroorganooligosilanes also react with N‐methylaniline to give PhMeN[SiMe2]2Cl (5), PhMeN[SiMe2]2NMePh (6), Cl[SiMe2]3NMePh (7), PhMeN[SiMe2]3NMePh (8), Cl[SiMe2]4NMePh (9), MeClSi[Si(NMePh)ClMe]2 (10), and MeSi[Si(NMePh)ClMe]3 (11). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis, X‐ray Structure and Properties of a Trinuclear Mixed‐Valence CoIII‐CoII‐CoIII Complex with Carboxamido N and Sulfinato S Donors
Authors: Rat Mathieu , Sousa Rodolphe Alves de , Tomas Alain , Frapart Yves , Tuchagues Jean‐Pierre , Artaud Isabelle 
Published: February 2003

AbstractAir oxidation of the six‐coordinate (Et4N)2[Co(N2S2)(CN)(CH3CN)] complex derived from N,N′‐(3‐mercapto‐3‐methylbutyryl)‐o‐phenylenediamine results in the formation of the trinuclear mixed‐valence complex (Et4N)4{CoII[CoIII{N2(SO2)2}(CN)(OH)]2} (3) where the thiolates have been oxidized to sulfinates. Its X‐ray structure reveals a linear arrangement of cobalt ions with bridging hydroxides and sulfinates. All cobalt ions are in a distorted octahedral environment. The mixed‐valence nature of this complex has been demonstrated by temperature‐dependent magnetic susceptibility measurements and by EPR spectroscopy both in the solid state and in solution. These data are in agreement with a high‐spin CoII. The IR spectrum shows the typical vibrations of cyanide and sulfinate at 2130 cm−1 (νCN), 1175 (νas/SO2) and 1030 cm−1 (νs/SO2). Trapping of CoII by chelex chromatography after treatment with aqueous HCl, or ” in situ” in aqueous solution, yields six‐coordinate low‐spin complexes with two different axial ligands Na3[Co{N2(SO2)2}(CN)(Cl)] (5a) and (Et4N)2[Co{N2(SO2)2}(CN)(H2O)] (5b). The pKa of the bound water molecule was estimated as 10.1 by pH‐metric titration. While 3 and 5a were inactive toward acetonitrile hydration, 5b catalyzes acetamide formation at 50 °C and pH 4.7 and 7 with low efficiency. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)