10150-87-5Relevant articles and documents
Gas-phase reaction of n-butyl acetate with the hydroxyl radical under simulated tropospheric conditions: Relative rate constant and product study
Veillerot,Foster,Guillermo,Galloo
, p. 235 - 243 (1996)
The gas-phase reaction of n-butyl acetate with hydroxyl radicals has been studied in an environmental smog chamber at 298 K. atmospheric pressure, and simulated tropospheric concentrations The rate constant for this reaction has been determined by a relative method and the experimental result, relative to n-octane used as reference compound, is k = 5.2 ± 0.5 × 10-12 cm3 molecule-1 s-1 This value appears to be about 25% higher than absolute rate constants found in the literature, but agrees very well with the other relative determination. Two reaction products have been identified and their production yield has been estimated, each accounting for about (15 ± 5)% of the overall OH reaction processes The two observed products are 2-oxobutyl acetate (CH3-CO-O-CH2-CO-CH2-CH3) and 3-oxobutyl acetate (CH3-CO-O-CH2-CH2-CO-CH3) The accuracy of the relative rate constant obtained is examined considering the evolution of the reactivity of the alkoxy end of the esters. Formation mechanisms for the two observed products are proposed and the likely other degradation channels are discussed
Decomposition du percarbonate de O,O-t-butyle et O-isopropenyle en solution: acetonylation des esters, acides et nitriles
Lalande, Robert,Filliatre, Claude,Villenave, Jean-Jacques,Jaouhari, Rabih
, p. 149 - 159 (1984)
The free-radical decomposition of O,O-t-butyl and O-isopropenyl peroxycarbonate in substrates possessing mobile H-atoms (S-H) consists mainly in an induced chain process leading to acetonylated derivatives of the solvent.Fairly good yields are obtained but the acetonylation of functional substrates often gives mixtures of isomers.In the case of methyl acetate, the acetonylation occurs on the C-atoms adjacent to the carbonyl (acyloxy moiety) and to the O-atom (alkoxy moiety).However, the relative amounts of the isomeric products depend on the concentration of the peroxycarbonate solutions; at lowest concentration, methyl 4-oxopentanoate (acyloxy moiety) is obtained selectively.It is assumed that the free radicals issued from the solvent are able to abstract H-atoms of other molecules of solvent before adding to the double bond of the peroxycarbonate; the more the peroxycarbonate solution is diluted the more the transfers from the C-atom adjacent to the carbonyl to the radicals adjacent to the O-atom are favoured.In the case of methyl alkanoates, H-transfers from the α-C-atoms to β-radicals of the acyloxy moiety may account for the orientation of the process.Owing to similar H-transfer processes, the acetonylation of functional esters, of acids and nitriles is selective in most cases.
A New Acylation Catalyst
Ahmad, Saeed,Iqbal, Javed
, p. 114 - 115 (1987)
Cobalt(II) chloride catalyses the acylation of alcohols and amines with anhydrides in excellent yields.
Palladium(II)-catalyzed tandem annulation reaction of o-alkynylbenzoates with methyl vinyl ketone for the synthesis of isocoumarins
Wang, Huan,Han, Xiuling,Lu, Xiyan
, p. 8626 - 8631 (2013/09/12)
A palladium(II)-catalyzed highly regioselective tandem reactions of o-alkynylbenzoates with methyl vinyl ketone for the synthesis of isocoumarins was developed. It is a convenient, mild and environmentally benign reaction with moderate to high yield. The
METHOD FOR MANUFACTURING KETONE
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Page/Page column 7; 8-9, (2012/08/08)
A method for manufacturing a ketone, includes oxidizing an internal olefin or a cyclic olefin having a functional group containing a hetero atom and one carbon-carbon double bond or more at a position other than terminals of a molecule thereof in an amide-based solvent in the presence of water, a palladium catalyst, and molecular oxygen, without oxidizing the functional group, thereby bonding an oxo group to at least one of the carbon atoms constituting the carbon-carbon double bond. The amide-based solvent is represented by formula (1): wherein R1 represents an alkyl group having 1 to 4 carbon atoms; R2 and R3 each independently represent an alkyl group having 1 to 4 carbon atoms or an aryl group; and when R1 and R2 are alkyl groups, R1 and R2 may be bonded to each other to form a ring structure.
An unexpected oxidation of unactivated methylene C-H using DIB/TBHP protocol
Zhao, Yi,Yim, Wai-Leung,Tan, Chong Kiat,Yeung, Ying-Yeung
supporting information; experimental part, p. 4308 - 4311 (2011/10/08)
An in situ generated hypervalent iodine species, bis(tert-butylperoxy) iodobenzene, was used as a peroxy radical source for the oxidation of unreactive, remote, and isolated alkyl (cyclic or aliphatic) esters and amides to the corresponding keto compounds under very mild conditions.
Self-assembled bidentate ligands for ru-catalyzed anti-Markovnikov hydration of terminal alkynes
Chevallier, Floris,Breit, Bernhard
, p. 1599 - 1602 (2008/02/02)
(Figure Presented) In pairs: Bidentate ligands are generated by the self-assembly of monodentate ligands through complementary hydrogen bonding. A ruthenium complex bearing such self-assembled heterodimeric ligands is used as the catalyst in the regioselective hydration of terminal alkynes. FG = functional group, Piv = pivaloyl.
Development and comparison of the substrate scope of Pd-catalysts for the aerobic oxidation of alcohols
Schultz, Mitchell J.,Hamilton, Steven S.,Jensen, David R.,Sigman, Matthew S.
, p. 3343 - 3352 (2007/10/03)
(Chemical Equation Presented) Three catalysts for aerobic oxidation of alcohols are discussed and the effectiveness of each is evaluated for allylic, benzylic, aliphatic, and functionalized alcohols. Additionally, chiral nonracemic substrates as well as chemoselective and diastereoselective oxidations are investigated. In this study, the most convenient system for the Pd-catalyzed aerobic oxidation of alcohols is Pd(OAc)2 in combination with triethylamine. This system functions effectively for the majority of alcohols tested and uses mild conditions (3 to 5 mol % of catalyst, room temperature). Pd(IiPr)(OAc)2(H2O) (1) also successfully oxidizes the majority of alcohols evaluated. This system has the advantage of significantly lowering catalyst loadings but requires higher temperatures (0.1 to 1 mol % of catalyst, 60°C). A new catalyst is also disclosed, Pd(IiPr)(OPiv)2 (2). This catalyst operates under very mild conditions (1 mol %, room temperature, and air as the O2 source) but with a more limited substrate scope.
Chemistry of Dioxiranes. 21. Thermal Reactions of Dioxiranes
Singh, Megh,Murray, Robert W.
, p. 4263 - 4270 (2007/10/02)
Thermolysis of dioxiranes in solutions of their parent ketones or in mixtures of the parent ketone and a foreign ketone leads to the formation of esters.The results are explained by postulating a free-radical mechanism involving H atom abstraction from the ketones.The resulting radicals are converted to the observed esters by reaction with acyloxy radicals derived from homolysis of the dioxiranes.Autodecomposition of dimethyldioxirane in acetone solution at room temperature gives methyl acetate at a very slow rate.When catalyzed by BF3 etherate the same decomposition proceeds much more rapidly and is accompanied by acetol formation.
Cobalt(II) Chloride Catalyzed Acylation of Alcohols with Acetic Anhydride: Scope and Mechanism
Iqbal, Javed,Srivastava, Rajiv Ranjan
, p. 2001 - 2007 (2007/10/02)
Cobalt(II) chloride catalyzes the acetylation of a variety of alcohols with acetic anhydride in excellent yield.Primary hydroxyl groups can be selectively acylated in the presence of secondary and tertiary ones while the secondary hydroxyl groups can be preferentially acetylated in the presence of tertiary ones.Tertiary alcohols have been found to give ketones, acetoacetates, olefins, and diketene in addition to the acetate.The β-hydroxy esters and ketones can be acylated under these conditions without any elimination, and this reaction has been compared with 4-(dimethylamino)pyridine (DMAP)-mediated acylations where elimination of the resulting β-acetoxy carbonyl compound is observed.A detailed investigation of the acylation of tertiary alcohols has revealed that these reactions proceed via a tertiary alkoxy radical and ketene.A mechanism for these acylations is proposed by invoking an electron-transfer process.
