1072-21-5Relevant academic research and scientific papers
Oxidation by Cobalt(III) Acetate. Part 4. Kinetics and Mechanism of the Oxidation of Glycols in Acetic Acid
Morimoto, Takashi,Hirano, Masao
, p. 1087 - 1090 (1982)
The oxidative cleavage of 1,2-glycols by cobalt(III) acetate in acetic acid was studied kinetically in order to clarify the reaction mechanism.The rates were first-order in both cobalt(III) acetate and substrate for the oxidation of all the diols used. cis-Cyclopentane-1,2-diol and decalin-9,10-diol were more rapidly oxidized than the corresponding trans-isomers, respectively, whereas cis-cyclohexane-1,2-diol was more slowly oxidized than the trans-isomer.The oxidation of trans-2-methoxycyclohexanol was much slower than that of the corresponding diol.The mechanism involving the formation of a bidentate complex between cobalt(III) acetate dimer and glycol is discussed.
Solvent Effect in the Thermal Decomposition Reaction of trans-3,3-Dimethyl-5,6-tetramethylene-1,2,4-trioxacyclohexane
Eyler, Gladys N.,Canizo, Adriana I.,Mateo, Carmen M.,Alvarez, Elida E.,Cafferata, Lazaro F. R.
, p. 8457 - 8460 (1999)
The kinetic data of the thermal decomposition reaction of trans-3,3-dimethyl-5,6-tetramethylene-1,2,4-trioxacyclohexane has been measured in different solvents (benzene, toluene, 2-propanol, 2-methoxyethanol, and p-dioxane) at 0.02 mol kg-1 initial concentration and in the temperature range of 135.0-165.0°C. The enthalpy and entropy of activation of the unimolecular reaction of this trioxane in several organic solvents have been correlated through "isokinetic relationships" to validate the existence of a genuine solvent effect on that reaction.
Catalytic aerobic oxidation of diols under photo-irradiation: Highly efficient synthesis of lactols
Miyata, Atsushi,Furukawa, Mizuki,Irie, Ryo,Katsuki, Tsutomu
, p. 3481 - 3484 (2002)
Aerobic oxidation of 1, n- and 1,ω-diols with (ON)Ru(salen) 1 as the catalyst was found to give the corresponding lactols in almost quantitative yields. Furthermore, in the oxidation of 2,2-dimethylalkane-1,ω-diols, less sterically hindered ω-alcohols were found to be preferentially oxidized when (ON)Ru(salen) 6 was used as the catalyst. n-Decanol was preferentially oxidized in the presence of 2,2-dimethylpropanol also by using 6 as the catalyst.
Oxidation of Cyclohexene in the Presence of Transition-Metal-Substituted Phosphotungstates and Hydrogen Peroxide: Catalysis and Reaction Pathways
Song, Yuexiao,Xin, Feng,Zhang, Lexiang,Wang, Yong
, p. 4139 - 4147 (2017)
Homogeneous catalytic oxidations of cyclohexene by transition-metal-substituted phosphotungstates [PW11M(L)O39]m? (PW11M, M=CoII, CuII, FeIII, NiII, MnII, L=H2O or absence) with hydrogen peroxide in acetonitrile were experimentally studied. The catalytic activities of allylic oxidation were found to strongly depend on the transition metals, and PW11Co showed the highest activity. The product distribution and the catalyst stability were dominated by mole ratio of hydrogen peroxide to PW11M, whereby low or high mole ratios led to stable structure of PW11M and predominant formation of allylic oxidation products or decomposition of PW11M, respectively. Different from the activation of the allylic C?H bond by radicals, the oxidation of C=C double bond was based on tungsten-peroxo species. A reaction mechanism composed of radical and nonradical processes was proposed from NMR, EPR, and kinetic data, to describe the reaction pathways of cyclohexene oxidation.
Asymmetric syntheses of the N-terminal α-hydroxy-β-amino acid components of microginins 612, 646 and 680
Davies, Stephen G.,Fletcher, Ai M.,Hanby, Abigail R.,Roberts, Paul M.,Thomson, James E.
, p. 1756 - 1764 (2017)
The asymmetric syntheses of the N-terminal α-hydroxy-β-amino acid components of microginins 612, 646 and 680 are reported. Conjugate addition of lithium (R)-N-benzyl-N-(α-methylbenzyl)amide to the requisite (E)-α,β-unsaturated ester followed by in situ enolate oxidation with (?)-(camphorsulfonyl)oxaziridne (CSO) gave the corresponding anti-α-hydroxy-β-amino esters. Sequential Swern oxidation followed by diastereoselective reduction gave the corresponding syn-α-hydroxy-β-amino esters. Subsequent N-debenzylation (i.e., hydrogenolysis for microginin 612, and NaBrO3-mediated oxidative N-debenzylation for microginins 646 and 680) followed by acid catalysed ester hydrolysis gave the corresponding syn-α-hydroxy-β-amino acids, the N-terminal components of microginins 612, 646 and 680, in good yield. An analogous strategy for elaboration of the enantiopure anti-α-hydroxy-β-amino esters facilitated the asymmetric synthesis of the corresponding C(2)-epimeric α-hydroxy-β-amino acids.
Products of the gas-phase reaction of O3 with cyclohexene
Aschmann, Sara M.,Tuazon, Ernesto C.,Arey, Janet,Atkinson, Roger
, p. 2247 - 2255 (2003)
In the troposphere, alkenes react with OH radicals, NO3 radicals, and O3, with the O3 reactions often being an important transformation process during both daytime and nighttime. The reactions of O3 with alkenes lead to the production of OH radicals, often in high yield, and these reactions also lead to the formation of secondary organic aerosol. Products of the gas-phase reactions of O3 with cyclohexane and cyclohexene-d10 were studied in the presence of OH radical scavengers by gas. Cyclohexane and cyclohexene-d12 were used as OH radicals. In the cyclohexene reaction in the presence of sufficient cyclohexane to scavenge >95% of the OH radicals formed, 1.47 × 1014 molecule/cu cm of O3 consumed 1.62 × 1014 molecule/cu cm of cyclohexene, with a 3.5% yield of HC(O)OH which increased to 4.5% after 17 min. Addition of butanal to the reactant mixtures resulted in changes in the post-reaction API-MS spectra. Adipaldehyde could be formed from reaction of the thermalized Criegee intermediate (presumably the anti-intermediate) with water vapor. OH (or OD) radical formation yields were also measured from the reactions of O3 with propylene (40 ± 6%).
Formation of Dicarbonyl Compounds in the Flash Vacuum Pyrolysis of Saturated Bicyclic Peroxides
Bloodworth, A. J.,Baker, David S.,Eggelte, Henny J.
, p. 1034 - 1036 (1982)
Under flash vacuum pyrolysis, dioxabicycloalkanes (n = 3,4, and 5) isomerise to keto-aldehydes, MeCOnCHO, whereas dioxabicycloalkanes (n = 2,3, and 4) fragment to give, by loss of hydrogen and ethylene, mixtures of cycloalkane-1,4-diones and dialdehydes, OHCnCHO.
Catalytic properties of the polyoxometalate [Ti2(OH) 2As2W19O67(H2O)] 8- in selective oxidations with hydrogen peroxide
Donoeva,Trubitsyna,Al-Kadamany,Kortz,Kholdeeva
, p. 816 - 822 (2010)
The catalytic properties of the sandwich polyoxometalate [Ti 2(OH)2As2W19O67(H 2O)]8-, which contains two (B-α-As IIIW9O33) fragments linked together by a "belt" consisting of one octahedral WO(H2O)4+ and two square-pyramidal Ti(OH)3+ groups, have been investigated in the selective liquid-phase oxidation of organic compounds by aqueous hydrogen peroxide. The polyoxometalate shows high catalytic activity and selectivity in the oxidation of alkenes, alcohols, diols, and thioethers. The composition of the reaction products indicates that hydrogen peroxide is activated via a heterolytic mechanism. Pleiades Publishing, Ltd., 2010.
A novel and efficient asymmetric synthesis of carbon-14 labeled (S, S)-2,7-di-boc-diamino[1,8-14C2]suberic acid
Villani,Saunders,Shu,Heys
, p. 49 - 57 (2002)
Five hundred mCi of Potassium [14C]cyanide at a specific activity of 51 mCi/mmol was used to diastereoselectively introduce the carbon-14 label into 1,6-hexanedial via a thermodynamically controlled asymmetric Strecker reaction using (R)-(-)-2-phenylglycinol as the chiral auxiliary. The expected and predominant (R, S/S, R) diastereomer (2) was separated by preparative normal phase HPLC. The chiral auxiliary was removed by oxidation with lead tetraacetate and the resulting benzylimino nitrile exhaustively hydrolyzed in hydrochloric acid to give (S,S)-2,7-diamino[1,8-14C2]suberic acid (6). Subsequent acylation with di-tert-butyldicarbonate gave the title compound (1) with a radiochemical purity of 95,5%, a specific activity of 113 mCi/mmol, and an enantiomeric purity of 95.5% e.e. To our knowledge this is the first report of the asymmetric Strecker methodology being applied to the synthesis of a carbon-14 labeled amino acid. Copyright
Production of Hydroxy Acids: Selective Double Oxidation of Diols by Flavoprotein Alcohol Oxidase
Fraaije, Marco W.,Martin, Caterina,Trajkovic, Milos
, p. 4869 - 4872 (2020)
Flavoprotein oxidases can catalyze oxidations of alcohols and amines by merely using molecular oxygen as the oxidant, making this class of enzymes appealing for biocatalysis. The FAD-containing (FAD=flavin adenine dinucleotide) alcohol oxidase from P. chrysosporium facilitated double and triple oxidations for a range of aliphatic diols. Interestingly, depending on the diol substrate, these reactions result in formation of either lactones or hydroxy acids. For example, diethylene glycol could be selectively and fully converted into 2-(2-hydroxyethoxy)acetic acid. Such a facile cofactor-independent biocatalytic route towards hydroxy acids opens up new avenues for the preparation of polyester building blocks.
