431-03-8Relevant articles and documents
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Nakagawa et al.
, p. 269,273,274 (1960)
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Waters
, (1947)
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AZIRINYL AND DIAZIRINYL (CHLORIDE) ION PAIRS AS INTERMEDIATES
Krogh-Jespersen, Karsten,Young, Claire M.,Moss, Robert A.,Wiostowski, Marek
, p. 2339 - 2342 (1982)
Both ab initio calculations and experimental observations support the intermediacy of diazirinyl or azirinyl cation-chloride anion pairs in transformations (1), (2), and (4).
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Avery,Cvetanovic
, p. 3727 (1965)
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Cvetanovic
, p. 775 (1956)
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Reaction Kitenics in Acetyl Chemistry over a Wide Range of Temperature and Pressure
Anastasi, Christopher,Maw, Paul R.
, p. 2423 - 2434 (1982)
The molecular modulation spectrometer has been used to study the complex chemical kitenics involed in acetyl radical chemistry.This has involved direct monitoring of both acetyl and methyl radicals in the same experiment and over a variety of temperatures (263 /1019 molecule cm-3 = 2.7) conditions.These measurements have been complemented by a non-linear least-squares analysis of the experimental data and simple product studies.Rate data on four reactions and the absorption cross-section of the acetyl radical at 223 nm have been determined in this way.Unimolecular rate theory, based on Kassel integrals, has been applied to the pressure-dependent formation and decay of the radical to extract limiting values for the rate constants at T = 303 and 343 K.
Synthesis of 2,3-butanedione over TS-1, Ti-NCl, TiMCM-41, Ti-Beta, Fe-Si, Fe-Beta and VS-1 zeolites
Beltramone, Andrea,Gomez, Marcos,Pierella, Liliana,Anunziata, Oscar
, p. 610 - 611 (2000)
The purpose of this work is the synthesis of 2,3-butanedione (diacetyl) by selective oxidation of 2-butanone (methyl ethyl ketone) in the presence of O2 and H2O2 30% as oxidants. All the tests were performed over several selective oxidation zeolite catalysts, synthesized and characterized in our laboratory.
Synthesis of Dialkyl- and Alkylacylrhenium Complexes by Alkylation of Anionic Rhenium Complexes at the Metal Center. Mechanism of a Double Carbonylation Reaction That Proceeds via the Formation of Free Methyl Radicals in Solution
Goldberg, Karen I.,Bergman, Robert G.
, p. 1285 - 1299 (1989)
The site of alkylation of salts of acylrhenates such as Li(1+)(1-) (1) can be controlled by adjusting the hardness of the alkylating agent.Thus, treatment of 1 with the hard alkylating agent (CH3)3OPF6 gives predominantly the clssical Fischer carbene complex Cp(CO)2Re=C(OCH3)(CH3) (2), whereas reaction with the softer electrophile CH3I leads almost exclusively to the new metal-alkylated complex Cp(CO)2Re(CH3)(COCH3) (3).The structure of 3 has been determined by X-ray diffraction.The availability of this material, a relatively rare example of astable alkylacylmetal complex, has provided an opportunity to study the products and mechanisms of its carbon-carbon bond-forming decomposition reactions.Thermally, the alkyl acyl complex undergoes simple reductive elimination, leading (in the presence of a metal-scavenging ligand L) to a quantitative yield of acetone and CpRe(CO)2(L).Photochemically, a more complicated reaction takes place, especially under 20 atm of CO, where CpRe(CO)3 and 2,3-butanedione are formed.Strikingly, irradiation of Cp(CO)2Re(CH3)2 (9) under 20 atm of CO gives products identical with those formed from 3.Labeling experiments using (13)CO and mixtures of acetyl- and propionylrhenium complexes are inconsistent with a mechanism involving simple migratory CO insertion followed by reductive elimination.They are, however, consistent with metal-carbon bond homolysis leading to methyl and acetyl radicals, followed by carbonylation of the methyl radicals to give a second source of acetyl radicals; these reactive intermediates then dimerize to give 2,3-butanedione.Confirmation of this mechanism was obtained by trapping all the initially formed radicals withhalogen donors.BrCCl3, proved to be much more efficient than CCl4 for this purpose: irradiation of alkyl acyl complex 3 in the presence of BrCCl3 diverted the reaction completely from 2,3-butanedione production, giving instead CH3Br, CH3COBr, Cp(CO)2Re(CH3)Br, and Cp(CO)2Re(CH3CO)Br.
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Arnett et al.
, p. 2482,2483, 2485 (1962)
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OXIDATION OF ALIPHATIC KETONES BY BROMAMINE-B: A KINETIC STUDY
Mahadevappa, D.S.,Mohan, K.,Ananda, S.
, p. 4857 - 4866 (1986)
The kinetics of oxidation of propan-2-one, butan-2-one, pentan-2-one, pentan-3-one and 4-methyl pentan-2-one by sodium N-bromobenzenesulphonamide or bromamine-B (BAB) in perchloric acid medium was studied at 30 deg C.The rate shows a first order dependence each on and +> and is independent of .Variation of ionic strength of medium and addition of the reaction product benzenesulphonamide have no effect on the rate and the dielectric effect is positive.The proposed mechanism involves acid catalysed enolisation of ketone in the rate limiting step followed by a fast interaction with the oxidant.This is supported by the magnitude of inverse solvent isotope effect of 1.62 +/- 0.01 observed in D2O medium.Activation parameters Ea, ΔH*, ΔS*, ΔG* and log A have been calculated by studying the reaction at different temperatures (293-309 K).
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Gandini,Hackett
, p. 6195,6198 - 6204 (1977)
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Atmospheric Chemistry of Selected Hydroxycarbonyls
Aschmann, Sara M.,Arey, Janet,Atkinson, Roger
, p. 3998 - 4003 (2000)
Using a relative rate method, rate constants have been measured at 296 ± 2 K for the gas-phase reactions of the OH radical with 1-hydroxy-2-butanone, 3-hydroxy-2-butanone, 1-hydroxy-3-butanone, 1-hydroxy-2-methyl-3-butanone, 3-hydroxy-3-methyl-2-butanone, and 4-hydroxy-3-hexanone, with rate constants (in units of 10-12 cm3 molecule-1 s-1) of 7.7 ± 1.7, 10.3 ± 2.2, 8.1 ± 1.8, 16.2 ± 3.4, 0.94 ± 0.37, and 15.1 ± 3.1, respectively, where the error limits include the estimated overall uncertainty in the rate constant for the reference compound. Rate constants were also measured for reactions with NO3 radicals and O3. Rate constants for the NO3 radical reactions (in units of 10-16 cm3 molecule-1 s-1) were 1-hydroxy-2-butanone, 3 were observed, and upper limits to the rate constants of -19 cm3 molecule-1 s-1 were derived for all six hydroxycarbonyls. The dominant tropospheric loss process for the hydroxycarbonyls studied here is calculated to be by reaction with the OH radical.
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Nodzu,Goto
, (1940)
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Photo-oxidations of Acetoin and Biacetyl catalyzed by Tetrabutylammonium Decatungstate(4-) in Acetonitrile under Excess of Oxygen
Nomiya, Kenji,Maeda, Katsunori,Miyazaki, Toshiaki,Miwa, Makoto
, p. 961 - 962 (1987)
Under an excess of oxygen, the photo-oxidation of acetoin catalysed by (NBu4)4(W10O32) and based on irradiation (λ > 300 nm) of the charge-transfer band in acetonitrile solution has been investigated.After irradiating for 30 h the products were biacetyl and acetic acid.The acetic acid was produced from both the acetoin and biacetyl.The rate constant for each path was determined by computer simulation.The production of biacetylis based on dehydrogenation of acetoin in conjunction with the redox cycle of (W10O32)4- attained by reaction with O2, whereas the production of acetic acid from biacetyl is based on the photoexcitation of biacetyl complexed with (W10O32)4- and subsequent reactions with O2 and water.
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Davis,Rogers,Thiel
, p. 558 (1939)
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Sol-gel synthesis of ceria-zirconia-based high-entropy oxides as high-promotion catalysts for the synthesis of 1,2-diketones from aldehyde
Dinjar, Kristijan,Djerdj, Igor,Koj?inovi?, Jelena,Kukovecz, ákos,Markovi?, Berislav,Mileti?, Aleksandar,Nagy, Sándor Balázs,Sapi, Andras,Stenzel, David,Széchenyi, Aleksandar,Szenti, Imre,Tang, Yushu,Tatar, Dalibor,Varga, Gábor,Ziegenheim, Szilveszter
, (2021/10/20)
Efficient Lewis-acid-catalyzed direct conversion of aldehydes to 1,2-diketones in the liquid phase was enabled by using newly designed and developed ceria–zirconia-based high-entropy oxides (HEOs) as the actual catalysts. The synergistic effect of various cations incorporated in the same oxide structure (framework) was partially responsible for the efficiency of multicationic materials compared to the corresponding single-cation oxide forms. Furthermore, a clear, linear relationship between the Lewis acidity and the catalytic activity of the HEOs was observed. Due to the developed strategy, exclusively diketone-selective, recyclable, versatile heterogeneous catalytic transformation of aldehydes can be realized under mild reaction conditions.
Bioinspired oxidation of oximes to nitric oxide with dioxygen by a nonheme iron(II) complex
Bhattacharya, Shrabanti,Lakshman, Triloke Ranjan,Sutradhar, Subhankar,Tiwari, Chandan Kumar,Paine, Tapan Kanti
, p. 3 - 11 (2019/11/11)
The ability of two iron(II) complexes, [(TpPh2)FeII(benzilate)] (1) and [(TpPh2)(FeII)2(NPP)3] (2) (TpPh2 = hydrotris(3,5-diphenylpyrazol-1-yl)borate, NPP-H = α-isonitrosopropiophenone), of a monoanionic facial N3 ligand in the O2-dependent oxidation of oximes is reported. The mononuclear complex 1 reacts with dioxygen to decarboxylate the iron-coordinated benzilate. The oximate-bridged dinuclear complex (2), which contains a high-spin (TpPh2)FeII unit and a low-spin iron(II)–oximate unit, activates dioxygen at the high-spin iron(II) center. Both the complexes exhibit the oxidative transformation of oximes to the corresponding carbonyl compounds with the incorporation of one oxygen atom from dioxygen. In the oxidation process, the oxime units are converted to nitric oxide (NO) or nitroxyl (HNO). The iron(II)–benzilate complex (1) reacts with oximes to afford HNO, whereas the iron(II)–oximate complex (2) generates NO. The results described here suggest that the oxidative transformation of oximes to NO/HNO follows different pathways depending upon the nature of co-ligand/reductant.