1190-79-0Relevant academic research and scientific papers
An alternative pathway for production of acetonitrile: Ruthenium catalysed aerobic dehydrogenation of ethylamine
Corker, Emily C.,Mentzel, Uffe V.,Mielby, Jerrik,Riisager, Anders,Fehrmann, Rasmus
, p. 928 - 933 (2013)
The oxidative synthesis of acetonitrile from ethylamine was studied using a supported ruthenium catalyst. The reaction was conducted in both batch and flow processes and high conversions (over 85%) were achieved in both cases. Selectivity of both reactions was improved by optimisation of reaction conditions, achieving over 90% selectivity in the batch process and 80% selectivity in the continuous flow process. The use of a selective solid catalyst that utilises a feedstock that can be derived from biomass, dioxygen as the oxidant and water as the solvent represents a new, green route for the independent and efficient production of acetonitrile.
Water Oxidation Reaction Mediated by an Octanuclear Iron-Oxo Cluster
Deutscher, Jennifer,Corona, Teresa,Warm, Katrin,Engelmann, Xenia,Sobottka, Sebastian,Braun-Cula, Beatrice,Sarkar, Biprajit,Ray, Kallol
supporting information, p. 4925 - 4929 (2018/05/30)
A one-pot synthetic procedure yields the octanuclear FeIII complex [Fe8(μ4-O)4(μ-4-tBu-pz)12Cl4] (2). The molecular structure of 2 resembles the building units of iron-containing minerals like magnetite, ferrihydrite and maghemite. Based on mechanistic investigation we propose that in presence of Et3N, iron(III) pyrazolates are reduced to iron(II) pyrazolates, which then activate dioxygen to form 2. Complex 2 exhibits unique spectroscopic and electrochemical properties relative to those of the previously reported Fe8 clusters based on pyrazolate ligands. Furthermore, 2 can oxidize water to hydrogen peroxide, thereby mimicking the water splitting process taking place at the surface of magnetite. Compound 2 therefore acts as both structural and functional models of iron-containing minerals.
Mechanistic insights into the oxidative dehydrogenation of amines to nitriles in continuous flow
Corker, Emily C.,Ruiz-Martínez, Javier,Riisager, Anders,Fehrmann, Rasmus
, p. 5008 - 5015 (2015/11/03)
The oxidative dehydrogenation of various aliphatic amines to their corresponding nitrile compounds using RuO2/Al2O3 catalysts in air was successfully applied to a continuous flow reaction. Conversions of amines (up to >99%) and yields of nitriles (up to 77%) varied depending on reaction conditions and the amine utilised. The presence of water was found to be important for the activity and stability of the RuO2/Al2O3 catalyst. The Hammett relationship and in situ infrared spectroscopy were applied to divulge details about the catalytic mechanism of the oxidative dehydrogenation of amines over RuO2/Al2O3 catalysts.
Tungsten nitrido complexes as precursors for low temperature chemical vapor deposition of WNxCy films as diffusion barriers for Cu metallization
McClain, K. Randall,O'Donohue, Christopher,Koley, Arijit,Bonsu, Richard O.,Abboud, Khalil A.,Revelli, Joseph C.,Anderson, Timothy J.,McElwee-White, Lisa
supporting information, p. 1650 - 1662 (2014/02/14)
Tungsten nitrido complexes of the form WN(NR2)3 [R = combinations of Me, Et, iPr, nPr] have been synthesized as precursors for the chemical vapor deposition of WNxCy, a material of interest for diffusion barriers in Cu-metallized integrated circuits. These precursors bear a fully nitrogen coordinated ligand environment and a nitrido moiety (Wi - N) designed to minimize the temperature required for film deposition. Mass spectrometry and solid state thermolysis of the precursors generated common fragments by loss of free dialkylamines from monomeric and dimeric tungsten species. DFT calculations on WN(NMe 2)3 indicated the lowest gas phase energy pathway for loss of HNMe2 to be β-H transfer following formation of a nitrido bridged dimer. Amorphous films of WNxCy were grown from WN(NMe2)3 as a single source precursor at temperatures ranging from 125 to 650 C using aerosol-assisted chemical vapor deposition (AACVD) with pyridine as the solvent. Films with stoichiometry approaching W2NC were grown between 150 and 450 C, and films grown at 150 C were highly smooth, with a RMS roughness of 0.5 nm. In diffusion barrier tests, 30 nm of film withstood Cu penetration when annealed at 500 C for 30 min.
Matrix-IR spectroscopic investigations of the thermolysis and photolysis of diazoamides
Wentrup, Curt,Bibas, Herve,Kuhn, Arvid,Mitschke, Ullrich,McMills, Mark C.
, p. 10705 - 10717 (2013/11/19)
Matrix photolysis of N,N-dialkyldiazoacetamides 1a-d at 7-10 K results in either the formation of C-H insertion products (in case of N,N-dimethyl and N,N-diethyl diazoamides) or almost exclusive Wolff rearrangement to ketenes (in the case of the cyclic di
A mild, aromatization of cyclic compounds and oxidation of amino groups to carbonyls using o-iodoxybenzoic acid
Kacan,Cicek,Karabulut,Ozyildirim
, p. 7649 - 7650 (2013/08/23)
A new, mild and efficient method has been developed for the synthesis of aromatic compounds and some carbonyls via the oxidative aromatization of amino cyclic compound by using hypervalent iodine reagent in DMSO at ambient temperature. The facile synthetic accessibility and it is as mild as non-hazardous nature render o-iodoxybenzoic acid equivalent of Dess-Martin periodinane reagent in organic oxidations.
Investigations into the mechanism of the liquid-phase hydrogenation of nitriles over Raney-Co catalysts
Schaerringer, Peter,Mueller, Thomas E.,Lercher, Johannes A.
, p. 167 - 179 (2008/09/17)
The co-hydrogenation of acetonitrile and butyronitrile over Raney-Co was investigated in order to obtain insight into the mechanism underlying the formation of secondary amines. Acetonitrile was reduced much faster to the corresponding primary amine due to stronger adsorption on the catalyst surface. In parallel, dialkylimines were formed and subsequently converted to secondary amines. It is suggested that the dialkylimines are formed by reaction of partially hydrogenated intermediate species on the cobalt surface with amines. In this respect, n-butylamine was found to react much faster than ethylamine. The stronger inductive effect of the butyl chain is thought to facilitate nucleophilic attack of the amine at the α-C-atom of the surface species. By comparing the C2 and C4 balance for dialkylimines and dialkylamines, it was found that direct hydrogenation of the dialkylimine cannot be the only way of dialkylamine formation. Instead, it is suggested that alkyl group transfer occurs by reaction of a monoalkylamine with a dialkylimine and cross-transfer between two dialkylimines.
Novel and mild route to phthalocyanines and 3-iminoisoindolin1-ones via N,N-diethylhydroxylamine-promoted conversion of phthalonitriles and a dramatic solvent-dependence of the reaction
Luzyanin, Konstantin V.,Kukushkin, Vadim Yu.,Kopylovich, Maximilian N.,Nazarov, Alexey A.,Galanski, Markus,Pombeiro, Armando J. L.
body text, p. 135 - 142 (2009/04/07)
Refluxing a mixture of phthalonitrile C6R1R 2R3R4(CN)2 1 (R1-R 4 = H), or its substituted derivatives 2 (R1, R 3, R4 = H, R2 = Me), or 3 (R1, R4 = H, R2, R3 = Cl) (lequiv.) and N,N-diethylhy-droxylamine, Et2NOH, (4 equivs.) in methanol for 4 h results (Route A) in precipitation of the symmetrical (6 and 8) and an isomeric mixture of unsymmetrical (7) phthalocyanines, isolated in good (55-65 % ) yields. The reaction of phthalonitriles 1, 2, or 4 (R1, R 3, R4 = H, R2 = NO2) (4 equivs.) with Et2NOH (8 equivs.) in the presence of a metal salt MCl 2 (M = Zn, Cd, Co, Ni) (1 equiv.) in n-BuOH or without solvent results in the formation of metallated phthalocyanine species (9-17). Upon refluxing in freshlydistilled dry chloroform, phthalonitrile 1 or its substituted analogues 2, 3 or 5 (R1-R4 = F) (1 equiv.) react with N,N-diethylhydroxylamine (2 equivs.) affording 3-iminoisoindolin-1- ones 18-21 (Route B) isolated in good yields (55-80%). All the prepared compounds were characterized with C, H, and N elemental analyses, ESI-MS, IR, and compounds 18-21 also by ID (1H, 13C(1H]), and 2D (1H,15N-HMBC and 1H,13CHMQC, 1H,13C-HMBC) NMR spectroscopy.
Catalysed aerobic dehydrogenation of amines and an X-ray crystal structure of a bis(benzylamine) ruthenium(II) porphyrin species
Bailey, Alan J.,James, Brian R.
, p. 2343 - 2344 (2007/10/03)
The complex trans-[RuVI(tmp)(O)2] 1 (tmp = dianion of 5,10,15,20-tetramesitylporphyrin) catalytically dehydrogenates primary and secondary amines in the presence of air; possible reaction steps involve a disproportionation reaction that generates a RuII intermediate, as evidenced by the isolated bis(benzylamine) complex [RuII(tmp)-(PhCH2NH2)2] 2 which is characterised crystallographically.
DEHYDROGENATION, DEAMINATION AND DISPROPORTIONATION OF DIETHYLAMINE OVER HETEROPOLY COMPOUNDS
Ali, Abdel-Ghafffar A.,Ali, Laila I.
, p. 2047 - 2056 (2007/10/03)
In a continuous flow system, transformation of diethylamine over heteropoly compouhds was studied at 250 to 350 deg C.It was found that ammonium molybdophosphate and tungstophosphate are the most active catalysts while copper molybdophosphate is the most stable one. 12-Molybdophosphoric acid ahd its salts were highly selective catalysts for dehydrogenation of diethylamine to ethylidenethylamine whereas 12-tungstophosphoric acid and its salts directed the reaction selectively to deamination.The role of Lewis acidity of metal cations.Bronsted acidity and basic sites in the reaction mechanism is discussed.
