1200-06-2Relevant articles and documents
Size-selective catalysts in five functionalized porous coordination polymers with unsaturated zinc centers
Deng, Dongsheng,Guo, Hui,Ji, Baoming,Wang, Weizhou,Ma, Lufang,Luo, Feng
, p. 12611 - 12616 (2017)
The five reported structural isomorphic porous coordination polymers (PCPs) 1-5, namely, [Zn(L)(ip) (1), Zn(L)(aip) (2), Zn(L)(hip) (3), Zn(L)(nip) (4), and Zn(L)(HBTC) (5) (L = N4,N4′-di(pyridine-4-yl)biphenyl-4,4′-dicarboxamide, H2ip = isophthalic acid, H2aip = 5-aminoisophthalic acid, H2hip = 5-hydroxyisophthalic acid, H2nip = 5-nitroisophthalic acid, H3BTC = 1,3,5-benzenetricarboxylic acid)] were used to catalyze the acetylation of phenol. All these heterogeneous catalysts exhibit good catalytic efficiency and size-selectivity toward the acetylation of phenols owing to their unsaturated metal centers, non-coordinated amide, and suitable channel size and shape. Among them, 2 displays the highest catalytic activity and excellent cooperative catalysis due to the presence of basic non-coordinated amide groups.
Structure-activity relationship on human serum paraoxonase (PON1) using substrate analogues and inhibitors
Bargota, Rakesh S.,Akhtar, Mahmoud,Biggadike, Keith,Gani, David,Allemann, Rudolf K.
, p. 1623 - 1626 (2003)
Substrate analogues based on the parent compounds paraoxon and phenyl acetate were tested on human serum paraoxonase (PON1) to explore the active site of the enzyme. Replacement of the nitro group of paraoxon with an amine or hydrogen, as well as electronic changes to the parent compound, converted these analogues into inhibitors. Introduction of either electron-withdrawing or donating groups onto phenyl acetate resulted in reduction in their rate of hydrolysis by PON1.
A New and Selective Metal-Catalyzed Baeyer-Villiger Oxidation Procedure
G?ttlich, Richard,Yamakoshi, Koichi,Sasai, Hiroaki,Shibasaki, Masakatsu
, p. 971 - 973 (1997)
A new, highly selective and high yielding procedure is described for the Baeyer-Villiger oxidation, using a tin-catalyst and bis(trimethylsilyl) peroxide (BTP).
Use of Molecular Oxygen in the Baeyer-Villiger Oxidation The Influence of Metal Catalysts
Bolm, Carsten,Schlingloff, Gunther,Weickhardt, Konrad
, p. 3405 - 3408 (1993)
Baeyer-Villiger oxidation of ketones using molecular oxygen and benzaldehyde in the absence of metal catalysts afforded lactones in high yields.The catalytic activity of various metal salts has been studied.Key Words: Baeyer-Villiger oxidation, Molecular
Ligand-Promoted Palladium-Catalyzed C?H Acetoxylation of Simple Arenes
Valderas, Carolina,Naksomboon, Kananat,Fernández-Ibá?ez, M. ángeles
, p. 3213 - 3217 (2016)
The palladium-catalyzed C?H oxidation of simple arenes is an attractive strategy to obtain phenols, which have many applications in the fine chemicals industry. Although some advances have been made in this research area, low reactivity and selectivity are, in general, observed. This report describes a new catalytic system for the efficient C?H acetoxylation of simple arenes based on Pd(OAc)2 and a pyridinecarboxylic acid ligand.
Electron-transfer Chain (ETC) Promotion of Aromatic Substitution Reactions. Entry into the SON2 Mechanism via Ipso Radical Attack
Eberson, Lennart,Joensson, Lennart
, p. 133 - 134 (1981)
The oxidative electron-transfer chain mechanism, the SON2 mechanism, is shown to be initiated by benzoyl-oxyl radicals, since 4-fluoroanisole can be converted into a mixture of 4-methoxyphenyl acetate and benzoate (maximum ratio 10:1) in high yield by decomposing benzoyl peroxide in HOAc-KOAc at 78 deg C.
Electrophilic components in the electrochemical acetoxylation of substituted arenes
Burasov, Alexander V.,Petrosyan, Vladimir A.
, p. 196 - 197 (2008)
The mechanism of anodic acetoxylation of substituted arenes under conditions of undivided galvanostatic electrolysis in MeCN containing acetate is suggested and an important role of electrophilic components (AcOH or ZnCl2) catalyzing transformation of intermediate ipso-acetoxylated polysubstituted arenonium cations to corresponding ortho-acetoxylated arenonium cations, which give acetoxylation products after deprotonation, is experimentally proved.
Acetylation of phenols in organic solvent catalyzed by a lipase from chromobacterium viscosum
Nicolosi,Piatelli,Sanfilippo
, p. 2477 - 2482 (1992)
Lipase from Chromobacterium viscosum, absorbed on an inert support, was employed as catalyst for the esterification of monohydric phenols in organic solvent, with vinyl acetate as acyl donor. The effect of aromatic ring substitution on the initial rate of transesterification was investigated.
Bacteriogenic iron oxide as an effective catalyst for Baeyer-Villiger oxidation with molecular oxygen and benzaldehyde
Mandai, Kyoko,Hanata, Minae,Mitsudo, Koichi,Mandai, Hiroki,Suga, Seiji,Hashimoto, Hideki,Takada, Jun
, p. 9403 - 9407 (2015)
Iron oxide produced by iron-oxidizing bacteria, Leptothrix ochracea, (L-BIOX) obtained from a freshwater purification plant, Joyo City in Kyoto, Japan catalyzed Baeyer-Villiger oxidation with molecular oxygen in the presence of benzaldehyde at 25 °C more efficiently than usual iron compounds. L-BIOX can promote the reactions of various substrates to give the desired products in sufficient yields and was found to be reusable. Scanning transmission electron microscopy and 57Fe M?ssbauer spectroscopy revealed that no change of the surface structure of L-BIOX was observed even after four times of the recycling test and the oxidation state of iron in L-BIOX is trivalent before and after the oxidation of cyclohexanone. An investigation with analogous amorphous iron oxides which contain silicon revealed that the catalytic activity of L-BIOX might stem from a synergetic effect of iron and silicon in the structure.
Substituent Effect in o-Nitroperbenzoic Acid Oxidation of m- and p-Substituted Acetophenones
Token, Katsuo,Hirano, Kenji,Yokoyama, Tai,Goto, Katsumi
, p. 2766 - 2771 (1991)
The Baeyer-Villiger reaction of m- and p-substituted acetophenones (substituents: H, p-MeO, p-t-Bu, p-i-Pr, p-Et, p-Me, p-Cl, p-Br, m-MeO, m-Me, m-Cl) with o-nitroperbenzoic acid was studied in chloroform at 30 deg C.The rate constants for the general acid catalysis were measured at several concentrations of o-nitrobenzoic acid which acted as an acid catalyst.The uncatalyzed and acid-catalyzed rate constants obtained afforded ρ values of -2.16 and -4.11 with ?, respectively.The results indicated that the rate-determining step is the migration of the phenyl group in the peroxy acid-carbonyl adduct for all the substituents studied, whether the reaction is acid-catalyzed or not, and that the acid catalyst intervenes only in the formation of the acid-ketone adduct in the initial state and not in the migration step.The variation of the leaving group abilities required the variation of the substituent constants applied, whereas the acid intervention in the addition step was reflected only in the variation of the ρ value, not in the substituent constants to be applied.The smaller resonance demand for o-nitrobenzoic acid indicated that the structure of the transition state in the migration step was looser and that the position of the transition state was earlier than those for m-chloroperbenzoic acid.