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1.
Zeolites modified with CuI ions are efficient catalyst for ‘click’ reactions involving carbohydrates and aminoacid derivatives. Glycopeptides and oligosaccharides mimics as well as multivalent carbohydrate derivatives have been obtained in good to high yield using heterogeneous CuI-modified zeolite catalysts. Contrarily to expectation, pore sizes and internal shapes within zeolites were not a limitation and large glucosyl ditriazoles, disaccharide triazoles, and glucosylated triazolylaminoacids could easily be obtained. Such CuI-zeolite heterogeneous catalysts greatly facilitated products recovery, through an easy filtration-solvent evaporation sequence, thus offering a convenient alternative to current methods. 相似文献
2.
Sonja Herres‐Pawlis Dr. Tarimala Seshadri Ulrich Flörke Gerald Henkel Prof. Dr. 《无机化学与普通化学杂志》2009,635(8):1209-1214
The reaction of 2,2′‐Bis(2N‐(1,1′,3,3′‐tetramethyl‐guanidino))diphenylene‐amine (TMG2PA) ( 1 ) with CuI in MeCN results in the formation of [CuII(TMG2PAamid)I] ( 2 ) indicatingthat CuI is the target of an oxidative attack of the N‐H proton of the ligand which itself is converted to molecular hydrogen. In contrast, if [Cu(MeCN)4][PF6] is used as the CuI source, [CuI2(TMGbenz)2][PF6]2 ( 3 ) is obtained instead. The use of the non‐coordinating counterion [PF6]– apparently prevents CuI from oxidation but induces itself a cyclisation reaction within the ligand which results in the formation of a benzimidazole‐guanidine ligand. 相似文献
3.
Dr. Tamaz Guliashvili Patrícia V. Mendonça Dr. Arménio C. Serra Dr. Anatoliy V. Popov Dr. Jorge F. J. Coelho 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(15):4607-4612
The field of transition‐metal‐mediated controlled/“living” radical polymerization (CLRP) has become the subject of intense discussion regarding the mechanism of this widely‐used and versatile process. Most mechanistic analyses (atom transfer radical polymerization (ATRP) vs. single‐electron transfer living radical polymerization (SET‐LRP)) have been based on model experiments, which cannot correctly mimic the true reaction conditions. We present, for the first time, a determination of the [CuIBr]/[L] (L=nitrogen‐based chelating ligand) ratio and the extent of CuIBr/L disproportionation during CLRP of methyl acrylate (MA) in dimethylsulfoxide (DMSO) with Cu0 wire as a transition‐metal catalyst source. The results suggest that Cu0 acts as a supplemental activator and reducing agent of CuIIBr2/L to CuIBr/L. More importantly, the CuIBr/L species seem to be responsible for the activation of SET‐LRP. 相似文献
4.
Jian‐Jun Liu Zuo‐Yin Li Xiong Yuan Yao Wang Chang‐Cang Huang 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(6):599-602
The title complex, [Cu(C6H4N3)]n, was synthesized by the reaction of cupric nitrate, 1H‐benzotriazole (BTAH) and aqueous ammonia under hydrothermal conditions. The asymmetric unit contains three crystallographically independent CuI cations and two 1H‐benzotriazolate ligands. Two of the CuI cations, one with a linear two‐coordinated geometry and one with a four‐coordinated tetrahedral geometry, are located on sites with crystallographically imposed twofold symmetry. The third CuI cation, with a planar three‐coordinated geometry, is on a general position. Two CuI cations are doubly bridged by two BTA− ligands to afford a noncentrosymmetric planar [Cu2(BTA)2] subunit, and two [Cu2(BTA)2] subunits are arranged in an antiparallel manner to form a centrosymmetric [Cu2(BTA)2]2 secondary building unit (SBU). The SBUs are connected in a crosswise manner via the sharing of four‐coordinated CuI cations, Cu—N bonding and bridging by two‐coordinate CuI cations, resulting in a one‐dimensional chain along the c axis. These one‐dimensional chains are further linked by C—H...π and weak van der Waals interactions to form a three‐dimensional supramolecular architecture. 相似文献
5.
Adrien Bessaguet Quentin Blancart-Remaury Pauline Poinot Isabelle Opalinski Sébastien Papot 《Angewandte Chemie (International ed. in English)》2023,62(6):e202216787
Rotaxanes and molecular knots exhibit particular properties resulting from the presence of a mechanical bond within their structure that maintains the molecular components interlocked in a permanent manner. On the other hand, the disassembly of the interlocked architecture through the breakdown of the mechanical bond can activate properties which are masked in the parent compound. Herein, we present the development of stimuli-responsive CuI-complexed [2]catenanes as OFF/ON catalysts for the copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction. The encapsulation of the CuI ion inside the [2]catenanes inhibits its ability to catalyze the formation of triazoles. In contrast, the controlled opening of the two macrocycles induces the breaking of the mechanical bond, thereby restoring the catalytic activity of the CuI ion for the CuAAC reaction. Such OFF/ON catalysts can be involved in signal amplification processes with various potential applications. 相似文献
6.
CuI-zeolites proved to be an efficient heterogeneous catalyst for the one-pot two-step synthesis of triazoles from halides or tosylates, sodium azide, and alkynes. The step and atom economies of this cascade reaction as well as water used as solvent and catalyst recycling make such synthesis a trully green process. With selected substrates, the peculiar roles of CuI-zeolites as catalysts were highlighted. 相似文献
7.
Dr. Carolina Valderas Prof. Dr. Luis Casarrubios Prof. Dr. Agusti Lledos Dr. Manuel A. Ortuño Dr. María C. de la Torre Prof. Dr. Miguel A. Sierra 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(26):9015-9023
A smooth catalytic method to use phenols as the nucleophilic partner in the Nicholas reaction has been developed. The method uses either AgI or AuI catalysts with AgClO4 or AgBF4 as the most efficient catalysts tested. Neither additional additives nor cocatalysts were required and the formation of the corresponding phenol adducts occurred in excellent yields. The process has the single limitation of the inability of less nucleophilic phenols (4‐nitrophenol) to generate the corresponding adducts. Additionally, the reaction is highly diastereoselective. DFT calculations allow a catalytic cycle to be proposed that involves trimetallic intermediates; the rate‐determining step of the reaction is hydroxy‐group elimination in a cobalt–silver trimetallic intermediate. 相似文献
8.
Evidence of CuI/CuII Redox Process by X‐ray Absorption and EPR Spectroscopy: Direct Synthesis of Dihydrofurans from β‐Ketocarbonyl Derivatives and Olefins
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Hong Yi Zhixiong Liao Guanghui Zhang Guoting Zhang Chao Fan Xu Zhang Prof. Dr. Emilio E. Bunel Dr. Chih‐Wen Pao Prof. Dr. Jyh‐Fu Lee Prof. Dr. Aiwen Lei 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(52):18925-18929
The CuI/CuII and CuI/CuIII catalytic cycles have been subject to intense debate in the field of copper‐catalyzed oxidative coupling reactions. A mechanistic study on the CuI/CuII redox process, by X‐ray absorption (XAS) and electron paramagnetic resonance (EPR) spectroscopies, has elucidated the reduction mechanism of CuII to CuI by 1,3‐diketone and detailed investigation revealed that the halide ion is important for the reduction process. The oxidative nature of the thereby‐formed CuI has also been studied by XAS and EPR spectroscopy. This mechanistic information is applicable to the copper‐catalyzed oxidative cyclization of β‐ketocarbonyl derivatives to dihydrofurans. This protocol provides an ideal route to highly substituted dihydrofuran rings from easily available 1,3‐dicarbonyls and olefins. 相似文献
9.
Copper(II) and Sodium(I) Complexes based on 3,7‐Diacetyl‐1,3,7‐triaza‐5‐phosphabicyclo[3.3.1]nonane‐5‐oxide: Synthesis,Characterization, and Catalytic Activity
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《化学:亚洲杂志》2018,13(19):2868-2880
The reaction of 3,7‐diacetyl‐1,3,7‐triaza‐5‐phosphabicyclo[3.3.1]nonane (DAPTA) with metal salts of CuII or NaI/NiII under mild conditions led to the oxidized phosphane derivative 3,7‐diacetyl‐1,3,7‐triaza‐5‐phosphabicyclo[3.3.1]nonane‐5‐oxide (DAPTA=O) and to the first examples of metal complexes based on the DAPTA=O ligand, that is, [CuII(μ‐CH3COO)2(κO‐DAPTA=O)]2 ( 1 ) and [Na(1κOO′;2κO‐DAPTA=O)(MeOH)]2(BPh4)2 ( 2 ). The catalytic activity of 1 was tested in the Henry reaction and for the aerobic 2,2,6,6‐tetramethylpiperidin‐1‐oxyl (TEMPO)‐mediated oxidation of benzyl alcohol. Compound 1 was also evaluated as a model system for the catechol oxidase enzyme by using 3,5‐di‐tert‐butylcatechol as the substrate. The kinetic data fitted the Michaelis–Menten equation and enabled the obtainment of a rate constant for the catalytic reaction; this rate constant is among the highest obtained for this substrate with the use of dinuclear CuII complexes. DFT calculations discarded a bridging mode binding type of the substrate and suggested a mixed‐valence CuII/CuI complex intermediate, in which the spin electron density is mostly concentrated at one of the Cu atoms and at the organic ligand. 相似文献
10.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(40):12275-12279
Recently, CuI‐ and AgI‐based halide double perovskites have been proposed as promising candidates for overcoming the toxicity and instability issues inherent within the emerging Pb‐based halide perovskite absorbers. However, up to date, only AgI‐based halide double perovskites have been experimentally synthesized; there are no reports on successful synthesis of CuI‐based analogues. Here we show that, owing to the much higher energy level for the Cu 3d10 orbitals than for the Ag 4d10 orbitals, CuI atoms energetically favor 4‐fold coordination, forming [CuX4] tetrahedra (X=halogen), but not 6‐fold coordination as required for [CuX6] octahedra. In contrast, AgI atoms can have both 6‐ and 4‐fold coordinations. Our density functional theory calculations reveal that the synthesis of CuI halide double perovskites may instead lead to non‐perovskites containing [CuX4] tetrahedra, as confirmed by our material synthesis efforts. 相似文献
11.
Wenjiang Huang Jinfang Zhang Jianghua Li Chi Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(2):123-126
In the polymeric title compound, [CuI(C10H8N4)]n, the CuI atom is in a four‐coordinated tetrahedral geometry, formed by two I atoms and two pyridine N atoms from two different 4,4′‐(diazenediyl)dipyridine (4,4′‐azpy) ligands. Two μ2‐I atoms link two CuI atoms to form a planar rhomboid [Cu2I2] cluster located on an inversion centre, where the distance between two CuI atoms is 2.7781 (15) Å and the Cu—I bond lengths are 2.6290 (13) and 2.7495 (15) Å. The bridging 4,4′‐azpy ligands connect the [Cu2I2] clusters into a two‐dimensional (2‐D) double‐layered grid‐like network [parallel to the (10) plane], with a (4,4)‐connected topology. Two 2‐D grid‐like networks interweave each other by long 4,4′‐azpy bridging ligands to form a dense 2‐D double‐layered network. To the best of our knowledge, this interwoven 2‐D→2‐D network is observed for the first time in [Cu2I2]–organic compounds. 相似文献
12.
Four kinds of copper(I)-phenanthroline complexes ([CuI(phen)2]Cl, [CuI(phen)Cl]2, [CuI(phen)2]BF4, and CuI(phen)PPh3Cl) were prepared and used as catalysts for amination and amidation of aryl iodide to investigate the influence on the yields of products due to differences of the structures. These complexes were found to work as catalysts on these reactions and showed that the differences of structures of copper(I) complexes significantly influenced the yield of aryl-nitrogen bond forming processes. 相似文献
13.
Yasuyuki Miyoshi Takeo Akatsuka Shin‐ichi Okuoka Aki Tsukajima Mitsuaki Makino Makoto Saito Dr. Koji Yonehara 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(25):7941-7949
Further study of our aerobic intermolecular cyclization of acrylic acid with 1‐octene to afford α‐methylene‐γ‐butyrolactones, catalyzed by the Pd(OCOCF3)2/Cu(OAc)2 ? H2O system, has clarified that the accumulation of water generated from oxygen during the reaction causes deactivation of the Cu cocatalyst. This prevents regeneration of the active Pd catalyst and, thus, has a harmful influence on the progress of the cyclization. As a result, both the substrate conversion and product yield are efficiently improved by continuous removal of water from the reaction mixture. Detailed analysis of the kinetic and spectroscopic measurements performed under the condition of continuous water removal demonstrates that the cyclization proceeds in four steps: 1) equilibrium coordination of 1‐octene to the Pd acrylate species, 2) Markovnikov‐type acryloxy palladation of 1‐octene (1,2‐addition), 3) intramolecular carbopalladation, and 4) β‐hydride elimination. Byproduct 2‐acryloxy‐1‐octene is formed by β‐hydride elimination after step 2). These cyclization steps fit the Michaelis–Menten equation well and β‐hydride elimination is considered to be a rate‐limiting step in the formation of the products. Spectroscopic data agree sufficiently with the existence of the intermediates bearing acrylate (Pd? O bond), η3‐C8H15 (Pd? C bond), or C11H19O2 (Pd? C bond) moieties on the Pd center as the resting‐state compounds. Furthermore, not only CuII, but also CuI, species are observed during the reaction time of 2–8 h when the reaction proceeds efficiently. This result suggests that the CuII species is partially reduced to the CuI species when the active Pd catalytic species are regenerated. 相似文献
14.
Dr. Lydie Harmand Romain Lambert Dr. Luca Scarpantonio Dr. Nathan D. McClenaghan Dr. Dominique Lastécouères Dr. Jean‐Marc Vincent 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(48):16231-16239
A detailed study on the photoreduction of the copper(II) precatalyst 1 to generate a highly reactive cuprous species for the copper(I)‐catalyzed alkyne‐azide cycloaddition (CuAAC) click reaction is presented. For the photoactive catalyst described herein, the activation is driven by a photoinduced electron transfer (PET) process harnessing a benzophenone‐like ketoprofenate chromophore as a photosensitizer, which is equally the counterion. The solvent is shown to play a major role in the CuII to CuI reduction process as the final electron source, and the influence of the solvent nature on the photoreduction efficiency has been studied. Particular attention was paid to the use of water as a potential solvent, aqueous media being particularly appealing for CuAAC processes. The ability to solubilize the copper‐tren complexes in water through the formation of inclusion complexes with β‐CDs is demonstrated. Data is also provided on the fate of the copper(I)‐tren catalytic species when reacting with O2, O2 being used to switch off the catalysis. These data show that partial oxidation of the secondary benzylamine groups of the ligand to benzylimines occurs. Preliminary results show that when prolonged irradiation times are employed a CuI to Cu0 over‐reduction process takes place, leading to the formation of copper nanoparticles (NPs). Finally, the main objective of this work being the development of photoactivable catalysts of practical value for the CuAAC, the catalytic, photolatent, and recycling properties of 1 in water and organic solvents are reported. 相似文献
15.
Direct Enantioselective Three‐Component Synthesis of Optically Active Propargylamines in Water
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Mutsuyo Ohara Yoshichika Hara Prof. Dr. Tohru Ohnuki Prof. Dr. Shuichi Nakamura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(29):8848-8851
An enantioselective three‐component reaction of aldehydes, amines, and alkynes in water by using a bis(imidazoline)–CuI catalysts having a hydrophobic substituent and sodium dodecyl sulfate as a surfactant was developed. The reaction was applied to a broad range of aldehydes and alkynes to give optically active propargylamines with excellent yields (up to 99 %) and enantiomeric excesses (up to 99 % ee). 相似文献
16.
Quan‐Guo Zhai Shu‐Ni Li Yu‐Cheng Jiang Man‐Cheng Hu 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(9):m249-m252
In the tetranuclear copper complex tetrakis[μ‐3,5‐bis(2‐pyridyl)‐1,2,4‐triazolido]bis[3,5‐bis(2‐pyridyl)‐1,2,4‐triazolido]dicopper(I)dicopper(II) dihydrate, [CuI2CuII2(C12H8N5)6]·2H2O, the asymmetric unit is composed of one CuI center, one CuII center, three anionic 3,5‐bis(2‐pyridyl)‐1,2,4‐triazole (2‐BPT) ligands and one solvent water molecule. The CuI and CuII centers exhibit [CuIN4] tetrahedral and [CuIIN6] octahedral coordination environments, respectively. The three independent 2‐BPT ligands adopt different chelating modes, which link the copper centers to generate a chair‐like tetranuclear metallomacrocycle with metal–metal distances of about 4.4 × 6.2 Å disposed about a crystallographic inversion center. Furthermore, strong π–π stacking interactions and O—H...N hydrogen‐bonding systems link the tetracopper clusters into a two‐dimensional supramolecular network. 相似文献
17.
Christian Nther Inke Jeß 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):m190-m192
The CuI cations in the title compound, [Cu(NCS)(C6H6N2O)2]n, are coordinated by N atoms from each of two mirror‐related nicotinamide ligands, as well as by one N atom of one thiocyanate ligand and one S atom of a symmetry‐related thiocyanate ligand, within a slightly distorted tetrahedron. The CuI cations and the thiocyanate anions are located on a crystallographic mirror plane and the nicotinamide ligands occupy general positions. The CuI cations are connected by the thiocyanate anions to form chains in the direction of the crystallographic a axis. These chains are connected by hydrogen bonds between the amide H atoms and the O atoms of adjacent nicotinamide ligands, to give a three‐dimensional structure. 相似文献
18.
Peter Haack Christian Limberg 《Angewandte Chemie (International ed. in English)》2014,53(17):4282-4293
Research on O2 activation at ligated CuI is fueled by its biological relevance and the quest for efficient oxidation catalysts. A rarely observed reaction is the formation of a CuII‐O‐CuII species, which is more special than it appears at first sight: a single oxo ligand between two CuII centers experiences considerable electron density, and this makes the corresponding complexes reactive and difficult to access. Hence, only a small number of these compounds have been synthesized and characterized unequivocally to date, and as biological relevance was not apparent, they remained unappreciated. However, recently they moved into the spotlight, when CuII‐O‐CuII cores were proposed as the active species in the challenging oxidation of methane to methanol at the surface of a Cu‐grafted zeolite and in the active center of the copper enzyme particulate methane monooxygenase. This Minireview provides an overview of these systems with a special focus on their reactivity and spectroscopic features. 相似文献
19.
Kazuya Yamaguchi Dr. Takamichi Oishi Tatsuyori Katayama Noritaka Mizuno Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(40):10464-10472
An easily prepared supported copper hydroxide on titanium oxide (Cu(OH)x/TiO2) showed high catalytic performance for the 1,3‐dipolar cycloaddition of organic azides to terminal alkynes in non‐polar solvents under anaerobic conditions. The reactions of various combinations of organic azides (four examples, including aromatic and aliphatic ones) and terminal alkynes (eleven examples, including aromatic, aliphatic, and double bond‐containing ones) exclusively proceeded to give the corresponding 1,4‐disubstituted‐1,2,3‐triazole derivatives in a completely regioselective manner. For the transformation of benzyl azide and ethynylbenzene with 0.12 mol % of Cu(OH)x/TiO2, the turnover frequency was 505 h?1 and the turnover number reached up to 800. These values were the highest among those with previously reported heterogeneous catalysts including Cu(OH)x/Al2O3. The observed catalysis was truly heterogeneous and the retrieved catalyst after the reaction could be reused at least three times with retention of its high catalytic performance. It was confirmed by the UV/Vis spectrum of Cu(OH)x/TiO2 and the amount of diyne formed that the CuII species in Cu(OH)x/TiO2 were reduced to CuI species by the alkyne–alkyne homocoupling at the initial stage of the reaction (during the pretreatment of Cu(OH)x/TiO2 with an alkyne). The catalytic reaction rate for the 1,3‐dipolar cycloaddition linearly increased with an increase in the amount of in situ generated CuI species. Therefore, the in situ generated CuI species would be the catalytically active species for the present 1,3‐dipolar cycloaddition. 相似文献
20.
Yi Han Nicholas F. Chilton Ming Li Chao Huang Prof. Hong Xu Prof. Hongwei Hou Boujemaa Moubaraki Stuart K. Langley Prof. Stuart R. Batten Prof. Yaoting Fan Prof. Keith S. Murray 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(20):6321-6328
From a predesigned grid, [CuII5CuI4L6] ? (I)2 ? 13 H2O ( 1 ), in which LH2 was a pyrazinyl‐triazolyl‐2,6‐substituted pyridine, we successfully synthesized an extended 3D complex, 1∞[{CuII5CuI8L6}{μ‐[CuI3(CN)6]}2 ? 2 CH3‐ CN] ( 2 ), that displayed unprecedented coexistence of all the five known coordination geometries of copper. Grid 1 displayed monovalent central metal exchange (CME) of CuI for AgI for the first time, as well as the formation of tri‐iodide in the crystalline state. These systems were investigated for their magnetic properties. Remarkably, grid 1 showed much higher catalytic activity than the Ag‐exchanged product for synthesis of a substituted triazole, 1‐benzyl‐4‐phenyl‐1H‐1,2,3‐triazole. 相似文献