- TGA and DTA studies on en and tmn complexes of Cu(II) chloride, nitrate, sulphate, acetate and oxalate
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Dynamic thermogravimetric and differential thermal analysis (TGA and DTA) of ethylenediamine (en) and tetramethylethylenediamine (tmn) complexes of a number of Cu(II) salts (chloride, nitrate, sulphate, acetate and oxalate) have been carried out. The thermal decomposition of these complexes occurs in steps involving dehydration, deamination and deanionation processes. However, majority of the weight loss steps in TGA are found to be composite in nature involving simultaneous loss of the component moieties in varying proportions. The ΔH and Ea values for various steps are deduced and the observed trends are analysed in terms of the nature of the processes underlying the steps and the differences in the nature of co-ordination of the ligands and/or the stereochemistry exhibited by the counter anions about the Cu(II) ion in the complex.
- Prabhumirashi,Khoje
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- Structural studies and anticancer activity of a novel (N6O 4) macrocyclic ligand and its Cu(II) complexes
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A novel (N6O4) macrocyclic ligand (L) and its Cu(II) complexes have been prepared and characterized by elemental analysis, spectral, thermal (TG/DTG), magnetic, and conductivity measurements. Quantum chemical calculations have also been carried out at B3LYP/6-31+G(d,p) to study the structure of the ligand and one of its complexes. The results show a novel macrocyclic ligand with potential amide oxygen atom, amide and amine nitrogen atoms available for coordination. Distorted square pyramidal ([Cu(L)Cl]Cl·2.5H2O (1), [Cu(L)NO3]NO 3·3.5H2O (2), and [Cu(L)Br]Br·3H 2O (4) and octahedral ([Cu(L)(OAc)2]·5H 2O (3)) geometries were proposed. The EPR data of 1, 2, and 4 indicate d1 x2 -y2 ground state of Cu(II) ion with a considerable exchange interaction. The measured cytotoxicity for L and its complexes (1, 2) against three tumor cell lines showed that coordination improves the antitumor activity of the ligand; IC50 for breast cancer cells are ≈8.5, 3, and 4 μg/mL for L and complexes (1) and (2), respectively.
- El-Boraey, Hanaa A.,Emam, Sanaa M.,Tolan, Dina A.,El-Nahas, Ahmed M.
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- A combined experimental and computational investigation on Tetrakis-μ-acetato-bis(acetamido)dicopper(II) and its application as a single source precursor for copper oxide
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The physico-chemical properties of the Tetrakis-μ-acetato-bis(acetamido) dicopper(II) [Cu(O2CCH3)2(CH 3CONH2)]2 (1), have been thoroughly investigated via an integrated multi-technique experimental-computational approach. In the newly found orthorhombic compound, as revealed by low temperature single-crystal X-ray studies, the complex is present as centrosymmetrical dimeric unit, has a paddle-wheel conformation with four acetate ligands bridging two symmetry-related CuII ions. The distorted octahedral coordination environment around the CuII ion is completed by an oxygen atom from an acetamide ligand. The compound sublimates, without premature side decompositions, at 180 °C. The structural, electronic and thermal behavior of the neutral complex (1) has been investigated. The present study suggests application of [Cu(O2CCH3) 2(CH3CONH2)]2 (1) as a precursor for copper-based materials by Chemical Vapor Deposition.
- Trivedi, Manoj,Nagarajan,Kumar, Abhinav,Molloy, Kieran C.,Kociok-K?hn, Gabriele,Sudlow, Anna L.
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- Dehydration of copper(II) acetate monohydrate
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The thermal dehydration of copper(II) acetate hydrate has been studied between 353 and 406 K, over a range of humidities. The dehydration is controlled by nucleation-and-growth kinetics at low temperatures, with an activation energy of 154 kJ.mol-1, which changes to contracting-disc kinetics at higher temperatures with a lower activation energy of 76 kJ.mol-1. Frequency factors have also been derived; the value for the high temperature process is low (107S-1) and that for the low temperature step is high (1017 s-1). Optical microscopy has been used to clarify the bulk kinetics; there is evidence for a reactive layer at the surface of the decomposing solid.
- Ball, M. C.,Portwood, L.
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- Protolytic dissociation mechanisms and comparative acid stabilities of palladium(II), zinc(II), copper(II), and nickel(II) complexes of alkylated dipyrrins
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Complexes of Pd(II), Cu(II), Ni(II), and Zn(II) with alkylated dipyrrins (Hdpm) were synthesized and characterized by physicochemical and spectroscopic methods. Protolytic dissociation kinetics of these complexes in benzene in the presence of acetic and trichloroacetic acid was studied. A protonated dipyrrin is the reaction product of protolytic dissociation of the complexes in acid solutions. The observed and true dissociation rate constants, as well as activation reaction parameters, were calculated. Kinetic models of the processes are proposed, and the patterns of influence of the ligand nature on dissociation kinetics were determined. The Pd(II) complexes proved to be much more stable than other those of the other metals, according to the results of the kinetic studies. The lability of the complexes strongly depends on the length and position of the alkyl substituent of the ligand. The dissociation of the Ni(II) complex gives a heteroligand complex at low concentrations of acid, but the complex undergoes full protolytic dissociation at higher concentrations of acid. The dissociation of the complex of Cu(II) is an equilibrium process, involving formation of the protonated form of the ligand.
- Rumyantsev, Evgeniy V.,Marfin, Yuriy S.
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- The kinetics of complex formation in the trithiadiazoletri[3,4-di(4-tert- butylphenyl)-pyrrole] macrocycle-copper(ii) acetate-dmfa-h2o system
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The paper presents the results of a study of the kinetics of coordination of a macroheterocyclic compound with an increased coordination cavity of the (3 + 3) McH3 composition consisting of sequentially alternating 1,3,4-thiadiazole and 3,4-bis
- Lomova,Mozhzhukhina,Danilova,Islyaikin
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- Preparation and characterization of copper(II) oxide thin films grown by a novel spray pyrolysis method
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A novel spray pyrolysis reactor was used to prepare thin films of CuO on silica substrates. The resulting films were characterized by X-ray diffraction, electron microscopy, optical and electrical measurements. The films were single phase, homogeneous, and uniform. The films were p-type semiconductors with room temperature resistivity of 102 ohm-cm. The p-type nature of the films was determined to be due to the presence of Cu(III).
- DeSisto, W.,Sosnowski, M.,Smith, F.,Deluca, J.,Kershaw, R.,et al.
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- Cobalt, nickel, copper and cadmium coordination polymers containing the bis(1,2,4-triazolyl)methane ligand
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Co(II), Ni(II), Cu(II) and Cd(II) coordination polymers containing the flexible ditopic bis(1,2,4-triazol-1-yl)methane ligand (Btm) have been prepared by reaction of equimolar quantities of the corresponding cobalt, nickel, copper and cadmium salts in EtOH solution. Structure solution and refinement of polycrystalline materials were performed by powder diffraction technique (XRPD), using conventional laboratory data. The results show that architecturally different coordination polymers were obtained depending on the counter-ion employed. The XRPD results show also that non-covalent interactions are driving forces for the occurrence of different structures.
- Marchetti, Fabio,Masciocchi, Norberto,Albisetti, Alessandro Figini,Pettinari, Claudio,Pettinari, Riccardo
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- Kinetic stability of complexes of some d-metals with 3,3'- bis(dipyrrolylmethene) in the binary proton-donor solvent acetic acid-benzene
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The kinetics of dissociation of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) binuclear homoleptic double-stranded helicates with bis(2,4,7,8,9- pentametyldipyrrolylmethen-3-yl)methane (H2L) of the [M 2L2] composition
- Antina,Guseva,V'yugin,Antina
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- On Verdigris, Part III: Crystal Structure, Magnetic and Spectral Properties of Anhydrous Copper(II) Acetate, a Paddle Wheel Chain
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Pure anhydrous Cu(CH3COO)2 was obtained both, by thermal dehydration of Cu(CH3COO)2·H2O and by drying a commercially purchased mixture of Cu(CH3COO)2·H2O and Cu(CH3COO)2 in a nitrogen atmosphere using P2O5 as drying agent. The crystal structure was solved ab initio from synchrotron X-ray powder diffraction (XRPD) data at 150 °C and from laboratory XRPD data at ambient conditions and found to be isotypic to anhydrous chromium(II), molybdenum(II) and rhodium(II) acetate. Cu(CH3COO)2 crystallizes in space group P1 (no. 2) with lattice parameters of a = 5.1486(3) ?, b = 7.5856(6) ?, c = 8.2832(6) ?, α = 77.984(4)°, β = 75.911(8)°, γ = 84.256(6)° at ambient conditions. Cu2(CH3COO)4 paddle wheels with short (2.6 ?) Cu–Cu distances form chains in a direction, which is the main motif in the crystal structure. Due to their identical structural main motif Cu(CH3COO)2·H2O and Cu(CH3COO)2 exhibit a similar bluish-green color, almost identical UV/Vis spectra and comparable magnetic properties. The temperature dependent magnetic susceptibility also indicates only weak inter-dimer spin exchange between neighbouring Cu2(CH3COO)4 paddle wheels.
- Bette, Sebastian,Costes, Alice,Kremer, Reinhard K.,Eggert, Gerhard,Tang, Chiu C.,Dinnebier, Robert E.
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- OPTICAL FILTER AND IMAGING APPARATUS
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An optical filter (1a) includes a light-absorbing layer (10). The light-absorbing layer absorbs light in at least a portion of the near-infrared region. When light with a wavelength of 300 to 1200 nm is incident on the optical filter (1a) at an incident angle of 0°, the optical filter (1a) satisfies given requirements. When light with a wavelength of 300 to 1200 nm is incident on the optical filter (1a) at incident angles of 0°, 30°, 35°, and 40°, the optical filter (1a) satisfies given requirements related to a normalized spectral transmittance. The normalized spectral transmittance is determined by normalization of a spectral transmittance for each incident angle so that the maximum of the spectral transmittance for each incident angle in the wavelength range of 400 to 650 nm is 100%.
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- LIGHT-ABSORBING COMPOSITION AND OPTICAL FILTER
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A light-absorbing composition according to the present invention includes: a light absorber formed by a phosphonic acid represented by the following formula (a) and copper ion, the light absorber being dispersed in the light-absorbing composition; a phosphoric acid ester allowing the light absorber to be dispersed; and a curable resin. When the light-absorbing composition is applied and cured on one principal surface of a transparent dielectric substrate to form a laminate consisting of a light-absorbing layer being a cured product of the light-absorbing composition and the transparent dielectric substrate, the laminate satisfies predetermined requirements.
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- Efficient Copper-Catalyzed Multicomponent Synthesis of N-Acyl Amidines via Acyl Nitrenes
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Direct synthetic routes to amidines are desired, as they are widely present in many biologically active compounds and organometallic complexes. N-Acyl amidines in particular can be used as a starting material for the synthesis of heterocycles and have several other applications. Here, we describe a fast and practical copper-catalyzed three-component reaction of aryl acetylenes, amines, and easily accessible 1,4,2-dioxazol-5-ones to N-acyl amidines, generating CO2 as the only byproduct. Transformation of the dioxazolones on the Cu catalyst generates acyl nitrenes that rapidly insert into the copper acetylide Cu-C bond rather than undergoing an undesired Curtius rearrangement. For nonaromatic dioxazolones, [Cu(OAc)(Xantphos)] is a superior catalyst for this transformation, leading to full substrate conversion within 10 min. For the direct synthesis of N-benzoyl amidine derivatives from aromatic dioxazolones, [Cu(OAc)(Xantphos)] proved to be inactive, but moderate to good yields were obtained when using simple copper(I) iodide (CuI) as the catalyst. Mechanistic studies revealed the aerobic instability of one of the intermediates at low catalyst loadings, but the reaction could still be performed in air for most substrates when using catalyst loadings of 5 mol %. The herein reported procedure not only provides a new, practical, and direct route to N-acyl amidines but also represents a new type of C-N bond formation.
- Van Vliet, Kaj M.,Polak, Lara H.,Siegler, Maxime A.,Van Der Vlugt, Jarl Ivar,Guerra, Célia Fonseca,De Bruin, Bas
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supporting information
p. 15240 - 15249
(2019/10/19)
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- INFRARED-ABSORBING COMPOSITION, INFRARED-CUT FILTER, AND IMAGING OPTICAL SYSTEM
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An infrared-absorbing composition according to the present invention includes: an infrared absorber formed by a phosphonic acid represented by the following formula (a) and copper ion; and a phosphoric acid ester allowing the infrared absorber to be dispersed. The phosphoric acid ester includes at least one of a phosphoric acid diester and a phosphoric acid monoester. R1 is a phenyl group or a phenyl group in which at least one hydrogen atom is substituted by a halogen atom. When molar contents of the phosphonic acid, the copper ion, and the phosphoric acid ester are respectively defined as CA mol, CC mol, and CE mol and a total molar content of reactive hydroxy groups is defined as CH mol, the relations CA/CEH/CC>1.95 are satisfied.
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- Copper(II)-mediated intermolecular amination of inert C(sp3)[sbnd]H bonds with simple alkylamines to construct α,α-disubstituted β-amino acid derivatives
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Disclosed herein is a copper(II)-mediated chelation-assisted intermolecular amination of inert C(sp3)[sbnd]H bonds using simple alkylamines as the amino source. A straightforward and step-economic alternative to α,α-disubstituted β-amino acid derivatives is provided consequently. This reaction features good functional group tolerance and relatively broad substrate scope. Furthermore, a coupling product between morpholine and radical inhibitor 2,6-di-tert-butyl-p-cresol (BHT) was isolated, indicating that a single electron transfer (SET) process might be involved in this transformation.
- Wang, Chunxia,Yang, Yudong
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supporting information
p. 935 - 940
(2017/02/18)
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- Coproduction method of crystallized cupric acetate and anhydrous cupric acetate
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The invention relates to a coproduction method of crystallized cupric acetate and anhydrous cupric acetate. The coproduction method comprises the following steps: preparing a saturated cupric nitrate solution A, and preparing a potassium bicarbonate solution B; adding the solution A into the solution B so as to obtain precipitated basic cupric carbonate, adding the precipitated basic cupric carbonate into an acetic acid solution, and performing a reaction so as to obtain the crystallized cupric acetate; collecting the mother liquor, concentrating the mother liquor continuously, adding a small amount of acetic acid, collecting the obtained precipitate, performing spin-drying, and performing drying so as to obtain the crystallized cupric acetate; and dehydrating the crystallized cupric acetate, thereby obtaining the anhydrous cupric acetate. As acetic anhydride is adopted as a dehydrating agent, a good dehydration capacity can be achieved, thorough dehydration can be achieved, and no impurity can be introduced. A trace amount of generated acetic acid can be removed by washing with a solvent, and the acetic anhydride can be recycled (containing a small amount of acetic acid) and can be continuously used as a raw material for synthesizing the crystallized cupric acetate.
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Paragraph 0031-0034; 0040-0042
(2017/08/27)
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- Copper-catalyzed intramolecular oxytrifluoromethylthiolation of unactivated alkenes
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A mild, versatile, and convenient method for efficient intramolecular oxytrifluoromethylthiolation of unactivated alkenes catalyzed by Cu(OAc)2 has been developed. The reactions were carried out under aerobic conditions and formed a variety of isoxazolines bearing a -SCF3 substituent. (Chemical Equation Presented).
- Zhu, Liping,Wang, Guoqiang,Guo, Quanping,Xu, Zhaoqing,Zhang, Di,Wang, Rui
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supporting information
p. 5390 - 5393
(2015/01/09)
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- Synthesis and crystal structures of [(iPr3P)2Cu(μ- ESiMe3)(InMe3)] (E = S, Se): Lewis acid-base adducts with chalcogen atoms in planar coordination
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The structures of [(iPr3P)2Cu(μ-SSiMe 3)(InMe3)] and [(iPr3P)2Cu(μ- SeSiMe3)(InMe3)] were determined by single-crystal X-ray diffraction. Both complexes are Lewis acid-base adducts of the InMe3 acceptor and the chalcogen donor atom linking a Me3Si group and a (iPr3P)2Cu moiety. They are very unstable under atmospheric conditions and decompose at ambient temperatures. Results of DFT calculations for these complexes and the related hypothetical [(Me 3P)2Cu(μ-SSiMe3)(InMe3)] compound show that the unusual planar coordination of the chalcogen atoms is due to steric crowding. Lewis acid-base adducts of trimethylindium and phosphane-stabilized copper(I) (trimethylsilyl)chalcogenolates were synthesized and characterized by X-ray crystal structure determination. They are very unstable under atmospheric conditions and decompose at ambient temperatures. DFT calculations reveal that the unusual planar coordination of the chalcogen atoms is due to steric crowding. Copyright
- Biedermann, Ralf,Kluge, Oliver,Fuhrmann, Daniel,Krautscheid, Harald
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p. 4727 - 4731
(2013/09/24)
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- Dual C-H activations of electron-deficient heteroarenes: Palladium-catalyzed oxidative cross coupling of thiazoles with azine N-oxides
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The palladium-catalyzed, copper-promoted cross-dehydrogenative-coupling (CDC) of electron-deficient thiazoles with azine N-oxides through dual C-H activations was developed. It was found that copper(II) pivalate was an efficient dual-function reagent for the oxidative cross-coupling reactions, playing the roles of both an oxidant and a C-H bond activation promoter. This methodology provides a simple way to construct 2-thiazolyl pyridine moiety.
- Fu, Xiao-Pu,Xuan, Qing-Qing,Liu, Li,Wang, Dong,Chen, Yong-Jun,Li, Chao-Jun
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p. 4436 - 4444
(2013/06/26)
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- Synthesis, characterization and protonation reaction of copper and palladium complexes bearing nitrite ligands in O,O-bidentate and N-monodentate bonding fashions
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Cu(Ph2P(o-C6H4C(O)H))2(NO 2) (3) has been prepared in high yield by treating [Cu(Ph 2P(o-C6H4C(O)H))2(NCMe)]BF 4 (2) with [Ph2PNPPh2]NO2 at ambient temperature. The nitrite ligand of 3 is coordinated to the Cu(I) center in an O,O-bidentate mode. Protonation of 3 releases NO molecule, which mimics the reactivity of the Type 2 Cu-NiRs. In contrast, reaction of [Pd(NCMe) 4](BF4)2 and Ph2P(o-C 6H4C(O)H) affords cis-[Pd(Ph2P(o-C 6H4C(O)H))2](BF4)2 (4) with the Pd2+ ion chelated by two phosphino-aldehyde moieties. The hemilabile formyl ligands of 4 can be displaced by NO2- to produce trans-Pd(Ph2P(o-C6H4C(O)H)) 2(NO2)2 (5), of which the nitrite ligands present an N-monodentate bonding feature. Protonation of 5 with HBF4, however, regenerates compound 4, likely via elimination of nitrous acid. The structures of 3-5 have been determined by an X-ray diffraction study.
- Chen, Chi-Shian,Dai, Huei-Fang,Chen, Chia-Hsiang,Yeh, Wen-Yann
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p. 396 - 400
(2011/11/01)
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- Copper(I) carboxylates of type [(nBu3P) mCuO2CR] (m = 1, 2, 3) - Synthesis, properties, and their use as CVD precursors
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Copper(I) carboxylates of type [(nBu3P)mCuO 2CR] (m = 1: 3a, R = Me; 3b, R = CF3; 3c, R = Ph; 3d, R = CH=CHPh. m = 2: 4a, R = Me; 4b, R = CF3; 4c, R = Ph; 4d, R = CH= CHPh. m = 3: 8a, R = Me; 8b, R = CF3; 8c, R = CH2Ph; 8d, R = (CH 2OCH2)3H; 8e, R = cC 4H7O) are accessible by following synthesis methodologies: the reaction of [CuO2CR] (1a, R = Me; 1b, R = CF3; 1c, R = Ph; 1d, R = CH=CHPh) with m equivalents of nBu3P (2) (m = 1, 2, 3), or treatment of [(nBu3P)mCuCl] (5a, m = 1; 5b, m = 2) with [KO2CCF3] (6). A more straightforward synthesis method for 8a - 8e is the electrolysis of copper in presence of HO2CR (7a, R = Me; 7b, R = CF3; 7c, R = CH2Ph; 7d, R = (CH2OCH2)3H; 7e, R = cC 4H7O) and 2, respectively. This method allows to prepare the appropriate copper(I) carboxylate complexes in virtually quantitative yield, analytically pure form, and on an industrial scale. IR spectroscopic studies reveal that the carboxylic units in 4, 5, and 8 bind in a unidentate, chelating or μ-bridging fashion to copper(I) depending on m and R. The thermal properties of 4, 6, and 8 were determined by TG and DSC studies. Based on TG-MS experiments a conceivable mechanism for the thermally induced decomposition of these species is presented. Hot-wall Chemical Vapor Deposition experiments (CVD) with precursor 4b showed that copper could be deposited at 480°C onto a TiN-coated oxidized silicon substrate. The copper films were characterized by SEM and EDX studies. Pure layers were obtained with copper particles of size 200 - 780 nm.
- Jakob, Alexander,Shen, Yingzhong,Waechtler, Thomas,Schulz, Stefan E.,Gessner, Thomas,Riedel, Ralf,Fasel, Claudia,Lang, Heinrich
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p. 2226 - 2234
(2009/05/08)
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- Dephenylation of triphenylbismuth(v) and antimony(v) derivatives in a methyl acrylate-methanol system in the presence of copper and palladium salts
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The influence of the central metal atom and acid residue in a molecule of organometallic compound Ph3MX2 (M = Bi, Sb; X = Cl, Br, OAc, O2CEt) on the direction and yield of dephenylation products in a methyl acrylate- methanol system in the presence of Cu(OAc)2 and Na2PdCl2(OAc)2 was studied at 50 °C in acetonitrile. The main product of dephenylation of the antimony compounds is methyl cinnamate (yield 0.31-1.59 moles per mole of the starting Ph 3SbX2), while anisole (0.55-0.97 mol) and halobenzene (0.67-1.04 mol) are those for compounds Ph3Bi(O2CR) 2 and Ph3BiHal2, respectively.
- Gushchin,Korotkova,Malysheva,Morugova,Moiseev
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p. 679 - 682
(2007/10/03)
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- Racemic and chiral expanded salen-type complexes derived from biphenol and binaphthol: Salbip and salbin
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The reaction of 2-fluoronitrobenzene with 2,2′-biphenol or (R)-binaphthol, followed by reduction and subsequent reaction of the resulting diamine with two equivalents of a salicylaldehyde, affords expanded salen-type ligands having backbones based on biphenol or binaphthol: salbipH2, (R)-salbinH2 and (R)-salbin(t-Bu)4H2. Deprotonation of these ligands with sodium methoxide or potassium hydride, followed by metallation with M(OAc)2 (M = Mn, Co, Ni, or Cu), affords the corresponding metal complexes in good yield (61-85%). The species containing Mn, Co, and Ni all have distorted octahedral geometry, as determined by X-ray crystallography. The ethereal oxygen atoms occupy two coordination sites with metal-oxygen distances ranging from 2.19 to 2.36 ?. The imine nitrogen atoms are trans to each other in the solid state, an impossible geometry in traditional salen-type complexes. The species containing Cu are distorted square planar and show much longer metal-ethereal oxygen distances ranging from 2.79 to 3.22 ?. The manganese complexes are competent catalysts for the epoxidation of olefins.
- Grill, Joseph M.,Reibenspies, Joseph H.,Miller, Stephen A.
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p. 3009 - 3017
(2007/10/03)
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- Thermogravimetric and differential thermal analysis of bipyridyl, ortho-phenylenediamine and 1,10 phenanthroline complexes of some Cu(II) salts
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Dynamic TGA and DTA studies on thermal decomposition of coordination complexes of bipyridyl, ortho-phenylenediamine and 1,10 phenanthroline with Cu(II) chloride, nitrate, sulphate, acetate and oxalate reveal that the process occurs through the stages: liquefaction, dehydration, deamination, deanionation and oxidation of Cu. All the steps are composite in nature consisting of simultaneous loss of the component moieties in varying proportions and the related ΔHs and Eas are significantly dependent on the nature of the co-anions and ligands.
- Prabhumirashi,Khoje
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p. 299 - 302
(2007/10/03)
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- Cu(II)-nitroxyl radicals as catalytic galactose oxidase mimics.
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Results from Hammett correlation studies and primary kinetic isotope effects for the CuCl-TEMPO catalysed aerobic benzyl alcohol oxidations are inconsistent with an oxoammonium based mechanism. We postulate a copper-mediated dehydrogenation mechanism, in which TEMPO regenerates the active Cu(II)-species. This mechanism is analogous to that observed for Galactose Oxidase and mimics thereof.
- Dijksman, Arne,Arends, Isabel W C E,Sheldon, Roger A
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p. 3232 - 3237
(2007/10/03)
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- Complexes of Schiff Bases and Intermediates in the Copper-Catalyzed Oxidative Heterocyclization by Atmospheric Oxygen
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After complexation with copper(II) ions, Schiff bases 1a-d may undergo an oxidative ring closure using atmospheric oxygen to give a number of imidazo[1,5-a]pyridines 2, an imidazo[1,5-a]imidazole 3, and an imidazo[5,1-a]isochinoline 4. This ligand oxidation can be performed with catalytic amounts of copper ions in the reaction. A catalytic cycle for the copper-catalyzed oxidative heterocyclization will be presented together with isolated copper complexes of Schiff bases 1a,b and intermediates 5 and 8 that were found by X-ray structure analyses which confirm this reaction scheme.
- Bluhm, Martin E.,Ciesielski, Michael,Goerls, Helmar,Walter, Olaf,Doering, Manfred
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p. 8878 - 8885
(2008/10/09)
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- 5-CYANO-10-HYDROXY-10,11-DIHYDRO-5H-DIBENZ[B,F]AZEPINE, THE PROCESSES FOR ITS PREPARATION AND FOR ITS CONVERSION INTO 5-CARBAMOYL-10-OXO-10, 11-DIHYDRO-5H-DIBENZ[B,F]AZEPINE OR INTO 5-CARBAMOYL-5H-DIBENZ[B,F]AZEPINE
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5-Cyano-10-Hydroxy-10,11-Dihydro-5H-Dibenzi[b,f]azepine and the process for its preparation.
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- 5-Cyano-10-hydroxy-10,11-dihydro-5H-dibenz[b,f]azepine, processes for its preparation and for its conversion into 5-carbamoyl-10-oxo-10,11-dihydro-5H-dibenz[b,f]azepine or into 5-carbamoyl-5H-dibenz[b,f]azepine
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A process and intermediates useful for the preparation of carbamazepine and oxcarbamazepine are disclosed.
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- Thermochemical reactivity of transition metal acetates and of a novel DMSO solvate of iron(II) acetate in molecular hydrogen
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The thermal decomposition of acetates of the transition metals Fe, Co, Ni, Mn and Cu in molecular hydrogen has been investigated by means of combined thermogravimetry/mass spectrometry, X-ray diffraction, and transmission as well as scanning electron microscopy. In the context of the reproducible preparation of the parent phases, i.e. the hydrated or anhydrous metal(II) acetates, single crystalline Fe3(CH3COO)6(DMSO)2, a novel DMSO solvate of iron(II) acetate, has been isolated and its crystal structure has been determined by means of X-ray diffraction. For the series of metal(II) acetates it has been found that the course of the thermal degradation in molecular hydrogen, in particular the formation of the gaseous products, strongly depends on the transition metal ion present in the parent compound. The detailed characterization of the solid products revealed, that phases exhibiting different catalytic activities and selectivities are formed as micro- or nanocrystalline metals and/or metal oxides.
- Ehrensberger,Schmalle,Oswald,Reller
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p. 139 - 149
(2008/10/09)
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- Phosphoraneiminato acetate cluster of copper and zinc. Crystal structures of [Cu4(NPEt3)2(O2CCH3) 6] and [Zn4(NPEt3)2(O2CCH3) 6]
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The anhydrous acetates of copper(II) and zinc react with the silylated phosphaneimine Me3SiNPEt3 in dichloromethane at 20 °C forming the mixed phosphoraneiminato acetate clusters [Cu4(NPEt3)2(O2CCH3) 6] (1), which forms emerald crystals, and colourless [Zn4(NPEt3)2 · (O2CCH3)6] (2). In spite of analogous composition the structures of 1 and 2 are completely different. In the asymmetric unit of 1 three copper atoms of an almost isosceles triangle are linked via two nitrogen atoms of the NPEt3- groups to form a trigonal bipyramidal aggregate. One of these three copper atoms is chelated by an acetate group, another one is connected with the fourth copper atom via three μ2-O2C-CH3 groups. The asymmetric units are associated via a μ2-O2C-CH3 group and a μ3-OC(O)CH3 group at a time so that infinite chains result. In 2 two zinc atoms are linked via the nitrogen atoms of the two NPEt3- groups to form an almost centrosymmetric four-membered ring. Both nitrogen atoms of the four-membered ring are connected with another zinc atom each. These zinc atoms again are linked with the zinc atoms of the Zn2N2 four-membered ring via two μ2-O2C-CH3 groups each and additionally coordinated with a terminal acetate ligand each.
- Ackermann, Hartmut,Weller, Frank,Neumueller, Bernhard,Dehnicke, Kurt
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p. 147 - 152
(2008/10/08)
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- Reactions of certain antimony(III, V) methyl derivatives with aliphatic alcohols in the presence of copper(II)
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Trimethylantimony and copper diacetate (or copper dipelargonate) in a 1:2 molar ratio substitute the hydrogen atom of the hydroxy group in aliphatic alcohols to form methyl alkyl ethers (yield up to 46%). The activity of alcohols toward methylation depends on the structure of the organic radical of the alcohol. Reactions of trimethylantimony diacetate or dibenzoate with alcohols in the presence of catalytic amounts of copper yield methyl alkyl ethers in 10-12% yields.
- Usyatinskii,Gushchin,Dodonov
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p. 1109 - 1112
(2007/10/03)
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- Novel (η2-Alkyne)copper(I) Carboxylate Complexes
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The reaction of Me3SiCCSiMe3 (1) with copper(I) carboxylates (2a: R = Me; 2b: R = Ph) yields the tetranuclear compounds 2-Me3SiCCSiMe3)2>2 (3a: R = Me; 3b: R = Ph) and dimeric 2-Me3SiCCSiMe3)>2 (6a: R = Me; 6b: R = Ph).Compounds 6a and 6b could only be characterized by using IR and NMR techniques, since in solution these compounds eliminate 1 to afford 3a or 3b, respectively.Complexes 3a and 3b can additionally be synthesized by the reaction of 2-Me3SiCCSiMe3)CuBr>2 (4) with (5a: R = Me; 5b: R = Ph).In 6 two carboxylate moieties are μ-bridging two (η2-Me3SiCCSiMe3)Cu building blocks, and the Me3SiCCSiMe3 fragments are each η2-coordinated to one copper atom.In 3 the Me3SiCCSiMe3 units are each η2-coordinated to two copper atoms and are perpendicularly orientated to the copper(I) core; the four copper atoms form a square-planar arrangement.Compounds 3a and 3b have been characterized by analytical and spectroscopic data (IR, 1H-, 13C-NMR, MS) and 3a by X-ray-analysis. - Key Words: Copper(I) complexes / Carboxylates / Alkynes
- Lang, Heinrich,Koehler, Katrin,Zsolnai, Laszlo
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p. 519 - 524
(2007/10/02)
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- [Cu4(NPMe3)3(O2C-CH3)5] - a Tetrameric Phosphorane Iminato Complex of Copper(II). Synthesis, Crystal Structure, Magnetic Behaviour, and EPR Spectrum
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The title compound and the corresponding benzoate complex [Cu4(NPMe3)3(O2C-C6H5)5] have been prepared by reactions of copper(II) acetate and copper(II) benzoate, respectively, with Me3SiNPMe3 in dichloromethane. Bothcomplexes are characterized by IR spectroscopy. The acetate complex is additionally characterized by the measurement of the magnetic susceptibi lity, by its EPR spectrum, and by a crystal structure determination. [Cu4(NPMe3)3(O2C-CH3)5]*CH2Cl2: Space group I41/A, Z=16, structure solutionwith 7960 independent reflections, R=0.044. Lattice dimensions at -70.d egree.C: a=b=3670.6; c=1091.9 pm. The structure consists of four Cu atoms which are arranged at the corners of a distorted tetrahedron with Cu...Cu distances between 290 and 318 pm. Three of the faces of the tetrahedron are linked by μ3-N atoms of the phosphorane iminato groups. Threeof the acetate ligands form chelates, the other two are monofunctionall y coordinated. Three of the copper atoms have a planar surrounding, the forth Cu atom has a (4+1) coordination.
- Meyer zu Koecker, R.,Pebler, J.,Friebel, C.,Dehnicke, K.,Fenske, D.
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- Cu(PMe3)4.
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Alkylation of copper(II) acetate with dialkylmagnesium reagents in the presence of tertiary phosphines gives the colorless copper(I) alkyl species. With sterically small phosphines, the complexes are ionic and possess left bracket Cu(PR//3)//4 right bracket cations and left bracket CuR//2 right bracket anions; larger phosphines give electrically neutral CuR(PR//3)//3 coordination complexes. Solution NMR data indicate that reversible phosphine dissociation is a facile process for all of the complexes and that extensive ion pairing occurs in nonpolar solvents. The X-ray crystal structure of the dimethylcuprate complex has been determined.
- Dempsey,Girolami
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p. 1208 - 1213
(2008/10/08)
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- SYNTHESIS OF Cu(II) AND Zn(II) AMINOCARBOXYLATES AND THEIR PROPERTIES.
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It was established by methods of chemical analysis, IR spectroscopy, and thermogravimetry that the reaction of Cu(II) and Zn(II) carboxylates of the corresponding monobasic aliphatic acids with gaseous ammonia in dimethylformamide leads to realization of coordination compounds of composition Cu(RCOO)//2 multiplied by (times) 2NH//3, Zn(CH//3COO)//2 multiplied by (times) 2NH//3.
- Prisyazhnyuk,Dzhambek
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- Kinetic Study of the Reduction of Molecular Oxygen by Cuprous Chloride and Cuprous Acetate in Pyridine
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The solution-phase kinetics of the reaction of cuprous chloride with molecular oxygen in pyridine were studied by monitoring product formation.The reaction was found to be third order in cuprous chloride and first order in oxygen by initial rate studies and pseudo-first-order rate constant determinations.A single rate law was found for solutions in which initial cuprous chloride concentrations were varied by more than a factor of 350 and initial oxygen concentrations were varied by more than a factor of 40.The integrated form of the resulting rate expression was found to precisely predict product vs. time curves.A more limited kinetic study of the reaction of cuprous acetate with oxygen in pyridine demonstrated that this reaction is first order in oxygen and second order in cuprous acetate.
- Hopf, Frederick R.,Rogic, Milorad M.,Wolf, James F.
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p. 4681 - 4686
(2007/10/02)
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- Metal salts of sulfurized olefin adducts of phosphorodithioic acids and organic compositions containing same
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A novel product formed by forming the metal salt of the product of reaction between a dialkyl or diaryl phosphorodithioic acid and a sulfurized olefin possesses among other things, good antiwear and antioxidant activity. Organic compositions containing a minor amount thereof also possess good lubricating characteristics.
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- Halogen derivatives of ascorbic acid and D-araboascorbic acid antioxidants
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The halogen derivatives of ascorbic acid and D-araboascorbic acid useful as antioxidants as well as a method for stabilizing oxidation-sensitive organic materials by incorporating said derivatives in oxidation sensitive materials.
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