141-05-9Relevant articles and documents
Maleates from diazoacetates and dilactones from head-to-head dimerisation of alkenyl diazoacetates using Grubbs' 2nd-generation ruthenium carbene catalyst
Hodgson, David M.,Angrish, Deepshikha
, p. 4902 - 4904 (2005)
Grubbs' 2nd-generation ruthenium carbene catalyst homocouples diazoacetates to maleates and also catalyses head-to-head dimerisation of alkenyl diazoacetates giving dienyl dilactones. The Royal Society of Chemistry 2005.
Catalytic Formation of Aziridines from Imines and Diazoacetates
Rasmussen, Kaare G.,Joergensen, Karl Anker
, p. 1401 - 1402 (1995)
A catalytic method for the preparation of aziridines from imines and diazoacetate is developed using copper complexes as catalyst; the synthetic, diastereo- and enantio-selective scope of the reaction are presented.
Cyclopropanation of alkenes with ethyl diazoacetate catalysed by ruthenium porphyrin complexes
Galardon, Erwan,Le Maux, Paul,Simonneaux, Gerard
, p. 927 - 928 (1997)
Ruthenium porphyrin complexes are active catalysts for the cyclopropanation of styrene derivatives by ethyl diazoacetate with good to very good diastereoselectivity; moderate enantiomeric excesses (34%) are observed using a chiral porphyrin as catalyst.
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Werner,Richards
, p. 4976 (1968)
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Stafford et al.
, p. 656,658 (1954)
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Mechanochemical defect engineering of HKUST-1 and impact of the resulting defects on carbon dioxide sorption and catalytic cyclopropanation
Barozzino-Consiglio, Gabriella,Filinchuk, Yaroslav,Grégoire, Nicolas,Hermans, Sophie,Steenhaut, Timothy
, p. 19822 - 19831 (2020)
Metal-organic frameworks (MOFs) are recognized as ideal candidates for many applications such as gas sorption and catalysis. For a long time the properties of these materials were thought to essentially arise from their well-defined crystal structures. It is only recently that the importance of structural defects for the properties of MOFs has been evidenced. In this work, salt-assisted and liquid-assisted grinding were used to introduce defects in a copper-based MOF, namely HKUST-1. Different milling times and post-synthetic treatments with alcohols allow introduction of defects in the form of free carboxylic acid groups or reduced copper(i) sites. The nature and the amount of defects were evaluated by spectroscopic methods (FTIR, XPS) as well as TGA and NH3temperature-programmed desorption experiments. The negative impact of free -COOH groups on the catalytic cyclopropanation reaction of ethyl diazoacetate with styrene, as well as on the gravimetric CO2sorption capacities of the materials, was demonstrated. The improvement of the catalytic activity of carboxylic acid containing materials by the presence of CuIsites was also evidenced.
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Armstrong,R.K.
, p. 618 - 620 (1966)
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Nakamura et al.
, p. 593 (1978)
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Cobalt carbaporphyrin-catalyzed cyclopropanation
Fields, Kimberly B.,Engle, James T.,Sripothongnak, Saovalak,Kim, Chungsik,Zhang, X. Peter,Ziegler, Christopher J.
, p. 749 - 751 (2011)
Cobalt complexes of N-confused porphyrins and benziphthalocyanine, which both feature organometallic bonds at the macrocycle cores, catalyze the cyclopropanation of styrene with a higher trans-selectivity than the corresponding porphyrin and phthalocyanine complexes. The Royal Society of Chemistry 2011.
Iron porphyrins catalyze the synthesis of non-protected amino acid esters from ammonia and diazoacetates
Aviv, Iris,Gross, Zeev
, p. 4477 - 4479 (2006)
Iron complexes of porphyrins (and corroles to a lesser extent) are the first catalysts to utilize ammonia for the synthesis of N-free amino acid esters. The Royal Society of Chemistry 2006.
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Klostergaard
, p. 108 (1958)
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Highly enantioselective ruthenium/PNNP-catalyzed imine aziridination: Evidence of carbene transfer from a diazoester complex
Egloff, Joel,Ranocchiari, Marco,Schira, Amata,Schotes, Christoph,Mezzetti, Antonio
, p. 4690 - 4701 (2013)
The ruthenium/PNNP complexes [RuCl(Et2O)(PNNP)]Y (Y = PF 6, 4PF6; BF4, 4BF4; or SbF 6, 4SbF6) (10 mol %) catalyze the enantioselective aziridination of imines with ethyl diazoacetate (EDA) as carbene source (PNNP = (1S,2S)-N,N′-bis[o-(diphenylphosphino)benzylidene]cyclohexane-1,2-diamine) . The highest enantioselectivity was obtained with 4SbF6, which aziridinated N-benzylidene-1,1-diphenylmethanamine (5a) to cis-ethyl 1-benzhydryl-3-phenylaziridine-2-carboxylate (cis-6a) with 93% ee at 0 C. To the best of our knowledge, this is the highest enantioselectivity ever obtained in transition metal-catalyzed asymmetric aziridination. Aziridine yields were overall moderate to low (up to 33% isolated yield of the cis isomer) because of the competitive formation of diethyl maleate (7). The scope of the catalyst was studied with p- and m-substituted imines. NMR spectroscopic studies with 13C- and 15N-labeled EDA indicate that aziridine 6a is formed by carbene transfer from an EDA complex, [RuCl(EDA)(PNNP)]PF6 (8), to the imine. The observation of a dinitrogen complex (9) gives further support to this mechanism. The EDA adduct 8 decomposes to the carbene complex [RuCl(CHCO2Et)(PNNP)]+ (10), whose reaction with EDA gives diethyl maleate. This unprecedented mechanism is rationalized on the basis of the nucleophilic nature of diazoalkanes, which is enhanced by coordination to a π-back-donating metal such as ruthenium(II).
Iridium-catalyzed aziridination of aliphatic aldehydes, aliphatic amines and ethyl diazoacetate
Kubo, Takashi,Sakaguchi, Satoshi,Ishii, Yasutaka
, p. 625 - 626 (2000)
Three-component coupling reactions of aliphatic aldehydes, aliphatic amines and ethyl diazoacetate to the corresponding aziridine derivatives has been achieved by the use of [Ir(cod)Cl]2 as a catalyst under mild conditions; for instance, the reaction of n-butyraldehyde, tert-butylamine and ethyl diazoacetate in the presence of a catalytic amount of [Ir(cod)Cl]2 in THF at -10 °C gave 1-tert-butyl-2-ethoxycarbonyl-3-propylaziridine in 85% yield in high stereoselectivity (cis: trans = 96:4).
A family of highly active copper(I)-homoscorpionate catalysts for the alkyne cyclopropenation reaction
Diaz-Requejo,Mairena,Belderrain,Nicasio,Trofimenko,Perez
, p. 1804 - 1805 (2001)
Equimolar mixtures of ethyl diazoacetate and alkynes can be converted into cyclopropenes in very high yields, at room temperature, through the intermediacy of readily available Cu(I) catalysts containing trispyrazolylborate ligands.
Metal-organic framework based on copper(I) sulfate and 4,4′- bipyridine catalyzes the cyclopropanation of styrene
Shi, Fa-Nian,Silva, Ana Rosa,Rocha, Joao
, p. 2196 - 2203 (2011)
The hydrothermal synthesis of a new metal-organic framework (MOF) formulated as Cu2(4,4′-bpy)2SO4· 6(H2O), [abbreviation: (1); bpy or 4,4′-bpy=4,4′- bipyridine; SO42-=sulfate group] has been reported. The structure of this MOF consists of Cu+ nodes connected via 4,4′-bpy to form infinite chains, with two neighboring chains further bridged on the nodes by SO42-, resulting in a 1-D double chain network. Guest water molecules reside in between the chains and are hydrogen-bonded to the O and S atoms from the nearest sulfate groups, leading to the formation of a 3-D supramolecular framework. This MOF is good heterogeneous catalyst for the cyclopropanation of styrene, with high trans cyclopropane diastereoselectivity and was recycled and reused for three consecutive cycles without a significant loss of catalytic activity.
Rh-mediated polymerization of carbenes: Mechanism and stereoregulation
Jellema, Erica,Budzelaar, Peter H. M.,Reek, Joost N. H.,De Bruin, Bas
, p. 11631 - 11641 (2007)
Ligand variation, kinetic investigations, and computational studies have been used to elucidate the mechanism of rhodium-catalyzed diazoalkane polymerization. Variations in the "N,O" donor part of the catalyst precursors (diene)RhI(N,O) result in different activities but virtually identical molecular weights, indicating that this part of the precursor is lost on forming the active species. In contrast, variation of the diene has a major effect on the nature of the polymer produced, indicating that the diene remains bound during polymerization. Kinetic studies indicate that only a small fraction of the Rh (1-5%) is involved in polymerization catalysis; the linear relation between polymer yield and Mw suggests that the chains terminate slowly and chain transfer is not observed (near living character). Oligomers and fumarate/maleate byproducts are most likely formed from other "active" species. Calculations support a chain propagation mechanism involving diazoalkane coordination at the carbon atom, N2 elimination to form a carbene complex, and carbene migratory insertion into the growing alkyl chain. N2 elimination is calculated to be the rate-limiting step. On the basis of a comparison of NMR data with those of known oligomer fragments, the stereochemistry of the new polymer is tentatively assigned as syndiotactic. The observed syndiospecificity is attributed to chain-end control on the rate of N2 elimination from diastereomeric diazoalkane complexes and/or on the migratory insertion step itself.
Synthesis, structure and reactivity of iridium complexes containing a bis-cyclometalated tridentate C^N^C ligand
Cheng, Shun-Cheung,Cheung, Wai-Man,Chong, Man-Chun,Ko, Chi-Chiu,Leung, Wa-Hung,Sung, Herman H.-Y.,Williams, Ian D.
, p. 8512 - 8523 (2021)
In an effort to synthesize cyclometalated iridium complexes containing a tridentate C^N^C ligand, transmetallation of [Hg(HC^N^C)Cl] (1) (H2C^N^C = 2,6-bis(4-tert-butylphenyl)pyridine) with various organoiridium starting materials has been studied. The treatment of1with [Ir(cod)Cl]2(cod = 1,5-cyclooctadiene) in acetonitrile at room temperature afforded a hexanuclear Ir4Hg2complex, [Cl(κ2C,N-HC^N^C)(cod)IrHgIr(cod)Cl2]2(2), which features Ir-Hg-Ir and Ir-Cl-Ir bridges. Refluxing2with sodium acetate in tetrahydrofuran (thf) resulted in cyclometalation of the bidentate HC^N^C ligand and formation of trinuclear [(C^N^C)(cod)IrHgIr(cod)Cl2] (3). On the other hand, refluxing [Ir(cod)Cl]2with1and sodium acetate in thf yielded [Ir(C^N^C)(cod)(HgCl)] (4). Chlorination of4with PhICl2gave [Ir(C^N^C)(cod)Cl]·HgCl2(5·HgCl2) that reacted with tricyclohexylphosphine to yield Hg-free [Ir(C^N^C)(cod)Cl] (5). Chloride abstraction of5with silver(i) triflate (AgOTf) gave [Ir(C^N^C)(cod)(H2O)](OTf) (6) that can catalyze the cyclopropanation of styrene with ethyl diazoacetate. Reaction of1and [Ir(CO)2Cl(py)] (py = pyridine) with sodium acetate in refluxing thf afforded [Ir(C^N^C)(HgCl)(py)(CO)] (7), in which the carbonyl ligand is coplanar with the C^N^C ligand. On the other hand, refluxing1with (PPh4)[Ir(CO)2Cl2] and sodium acetate in acetonitrile gave [Ir(C^N^C)(κ2C,N-HC^N^C)(CO)] (8), the carbonyl ligand of which istransto the pyridyl ring of the bidentate HC^N^C ligand. Upon irradiation with UV light8in thf was isomerized to8′, in which the carbonyl istransto a phenyl group of the bidentate HC^N^C ligand. The isomer pair8and8′exhibited emission at 548 and 514 nm in EtOH/MeOH at 77 K with lifetime of 84.0 and 64.6 μs, respectively. Protonation of8withp-toluenesulfonic acid (TsOH) afforded the bis(bidentate) tosylate complex [Ir(κ2C,N-HC^N^C)2(CO)(OTs)] (9) that could be reconverted to8upon treatment with sodium acetate. The electrochemistry of the Ir(C^N^C) complexes has been studied using cyclic voltammetry. Reaction of [Ir(PPh3)3Cl] with1and sodium acetate in refluxing thf led to isolation of the previously reported compound [Ir(κ2P,C-C6H4PPh2)2(PPh3)Cl] (10). The crystal structures of2-5,8,8′,9and10have been determined.
The effect of catalyst loading in copper-catalyzed cyclohexane functionalization by carbene insertion
Caballero, Ana,Diaz-Requejo, M. Mar,Trofimenko, Swiatoslaw,Belderrain, Tomas R.,Perez, Pedro J.
, p. 2848 - 2852 (2007)
A study of the variables that affect the insertion of the :CHCO 2Et group (formed from ethyl diazocetate, EDA) into the C-H bonds of cyclohexane in the presence of a TpxCu complex as the catalyst (Tpx = trispyrazolylborate ligand) has demonstrated an anomalous effect of the catalyst loading. The use of low concentrations of catalyst produces an increase in the yield of the C-H activation product ethyl cyclohexaneacetate. This effect has also been found in the case of other less elaborated catalysts such as [BpBr3Cu] or [(bipy)2-Cu][I]. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
One-pot production of diethyl maleate via catalytic conversion of raw lignocellulosic biomass
Cai, Zhenping,Chen, Rujia,Jiang, Lilong,Li, Fukun,Li, Xuehui,Long, Jinxing,Zhang, Hao
supporting information, p. 10116 - 10122 (2021/12/24)
The conversion of lignocellulose into a value-added chemical with high selectivity is of great significance but is a big challenge due to the structural diversities of biomass components. Here, we have reported an efficient approach for the one-step conversion of raw lignocellulose into diethyl maleate by the polyoxometalate ionic liquid [BSmim]CuPW12O40 in ethanol under mild conditions. The results reveal that all of the fractions in biomass, i.e., cellulose, lignin and hemicellulose, were simultaneously converted into diethyl maleate (DEM), achieving a 329.6 mg g-1 yield and 70.3% selectivity from corn stalk. Importantly, the performance of the ionic liquid catalyst [BSmim]CuPW12O40 was nearly twice that of CuHPW12O40, which can be attributed to the lower incorporation of the Cu2+ site in [BSmim]CuPW12O40. Hence, this process opens a promising route for producing bio-based bulk chemicals from raw lignocellulose without any pretreatment.
Iron/N-doped graphene nano-structured catalysts for general cyclopropanation of olefins
Bartling, Stephan,Beller, Matthias,Ferretti, Francesco,Formenti, Dario,Junge, Kathrin,Kreyenschulte, Carsten,Ragaini, Fabio,Sarkar, Abhijnan
, p. 6217 - 6221 (2020/08/24)
The first examples of heterogeneous Fe-catalysed cyclopropanation reactions are presented. Pyrolysis of in situ-generated iron/phenanthroline complexes in the presence of a carbonaceous material leads to specific supported nanosized iron particles, which are effective catalysts for carbene transfer reactions. Using olefins as substrates, cyclopropanes are obtained in high yields and moderate diastereoselectivities. The developed protocol is scalable and the activity of the recycled catalyst after deactivation can be effectively restored using an oxidative reactivation protocol under mild conditions. This journal is
