134339-50-7Relevant academic research and scientific papers
Baeyer-Villiger oxidation under Payne epoxidation conditions
Bradley, Tyne D.,Dragan, Andrei,Tomkinson, Nicholas C.O.
, p. 8155 - 8161 (2015)
A novel method for the Baeyer-Villiger oxidation of ketones has been developed and optimized. The transformation involves a transition metal-free activation of hydrogen peroxide under Payne epoxidation conditions. Reaction of a ketone with hydrogen peroxide in the presence of a nitrile under mildly basic reaction conditions leads to the corresponding ester. The transformation has been successfully applied to a range of ketones in moderate to excellent yields (30-91%) and good to excellent regioselectivities (7:1 to 20:1).
Continuous Flow Chemo-Enzymatic Baeyer-Villiger Oxidation with Superactive and Extra-Stable Enzyme/Carbon Nanotube Catalyst: An Efficient Upgrade from Batch to Flow
Szelwicka, Anna,Zawadzki, Przemys?aw,Sitko, Magdalena,Boncel, S?awomir,Czardybon, Wojciech,Chrobok, Anna
, p. 1386 - 1395 (2019)
Continuous flow chemo-enzymatic Baeyer-Villiger oxidation in the presence of exceptionally active Candida antarctica lipase B immobilized via simple physical adsorption on multiwalled carbon nanotubes has been investigated. The nanobiocatalyst was used to generate peracid in situ from ethyl acetate and 30 wt % aq. hydrogen peroxide as the primary oxidant. Application of the highly stable and active nanobiocatalyst in the Baeyer-Villiger oxidation of 2-methylcyclohexanone to 6-methyl-?-caprolactone after 8 h at 40 °C led to a high product yield (87%) and selectivity (>99%). Environmentally friendly ethyl acetate was applied as both solvent and the peracid precursor. To determine the most favorable reaction conditions, a series of experiments using various parameters was performed. The main contribution of this work is that it describes the first application of the nanobiocatalyst in a chemo-enzymatic Baeyer-Villiger oxidation in a flow system. Since the process was performed in a flow reactor, many improvements were achieved. First of all, substantially shorter reaction times as well as a significant increase in the product yield were obtained as compared to the batch process. Since peracids are unstable, a large increase in the safety of the process was demonstrated under mild conditions in this work. In summary, this work shows a particularly efficient upgrade in the studied processes by transfer from a batch to a flow system.
A robust chemo-enzymatic lactone synthesis using acyltransferase from Mycobacterium smegmatis
Drozdz,Hanefeld,Szymańska,Jarz?bski,Chrobok
, p. 37 - 40 (2016)
The new application of acyltransferase, isolated from Mycobacterium smegmatis for the chemo-enzymatic Baeyer-Villiger oxidation of cyclic ketones to lactones was demonstrated. Acyltransferase exhibited high activity, and high stability under harsh reaction conditions, like oxidation with 60% aq. H2O2 at 45°C. This paves the way to a novel robust chemo-enzymatic method for lactone synthesis with high yields.
Mutagenesis-Independent Stabilization of Class B Flavin Monooxygenases in Operation
Goncalves, Leticia C. P.,Kracher, Daniel,Milker, Sofia,Fink, Michael J.,Rudroff, Florian,Ludwig, Roland,Bommarius, Andreas S.,Mihovilovic, Marko D.
, p. 2121 - 2131 (2017)
This paper describes the stabilization of flavin-dependent monooxygenases under reaction conditions, using an engineered formulation of additives (the natural cofactors NADPH and FAD, and superoxide dismutase and catalase as catalytic antioxidants). This
Perdecanoic acid as a safe and stable medium-chain peracid for Baeyer-Villiger oxidation of cyclic ketones to lactones
Sitko, Magdalena,Szelwicka, Anna,Wojewódka, Andrzej,Skwarek, Andrzej,Tadasiewicz, Dariusz,Schimmelpfennig, Lech,Dziuba, Krzysztof,Morawiec-Witczak, Magdalena,Chrobok, Anna
, p. 30012 - 30018 (2019)
Stability studies dedicated to high-energy compounds for a series of linear peracids (C6-C12), including sensitivity to mechanical impulse (shock and friction), as well as electrical (spark) and thermal sensitivity (temperature and heat of decomposition), were presented in this work for the first time. Studies revealed that all peracids were insensitive to shock, while in the case of the other sensitivity tests sharp differences between results for C8 and C10 peracids were observed. Taking into account the relatively high initial temperature of decomposition (above 64 °C) perdecanoic acid was selected as a safe alternative to commonly used hazardous short-chain peracids. Next, a new method for the Baeyer-Villiger oxidation was presented. Oxidation of 2-adamantanone was chosen as a model reaction. Peroctanoic, perdecanoic and perdodecanoic acids were tested as oxidants. Peroctanoic acid was the most reactive but taking into account both safety and kinetic issues, perdecanoic acid was selected for the further studies. The influence of reaction conditions on reaction rate was investigated. Optimized reaction conditions were suggested (two-fold molar excess of peracid with respect to the ketone, toluene as a solvent, 35 °C). This exploratory study offers promise with regard to the development of safer alternatives to peracetic acid in industrial oxidation.
Synthesis of novel organoselenium as catalyst for Baeyer-Villiger oxidation with 30% H2O2
Ichikawa, Hayato,Usami, Yoshihide,Arimoto, Masao
, p. 8665 - 8668 (2005)
A novel diselenide was synthesized in good yield via only four steps from phenol, and was employed as the catalyst for the Baeyer-Villiger oxidation with 30% H2O2 to obtain lactones in good yields.
Titanium complexes of pyrrolylaldiminate ligands and their exploitation for the ring-opening polymerization of cyclic esters
Chuawong, Pitak,Hormnirun, Pimpa,Nanok, Tanin,Upitak, Kanokon,Wattanathana, Worawat
, p. 10964 - 10981 (2021/08/17)
A series of six-coordinate titanium complexes1-6supported by pyrrolylaldiminate ligands were preparedviathe reaction of 2 equivalents of ligands and Ti(OiPr)4in toluene at 70 °C. The X-ray structure of2revealed that the two ligands w
Benzyne-Mediated Esterification Reaction
Li, Yang,Shi, Jiarong,Zhao, Jinlong
supporting information, p. 7274 - 7278 (2021/10/01)
A benzyne-mediated esterification of carboxylic acids and alcohols under mild conditions has been realized, which is made possible via a selective nucleophilic addition of carboxylic acid to benzyne in the presence of alcohol. After a subsequent transesterification with alcohol, the corresponding esters can be produced efficiently. This benzyne-mediated protocol can be used on the modification of Ibuprofen, cholesterol, estradiol, and synthesis of nandrolone phenylpropionate. In addition, benzyne can also be used to promote lactonization and amidation reaction.
Polycyclic ketone monooxygenase from the thermophilic fungus Thermothelomyces thermophila: A structurally distinct biocatalyst for bulky substrates
Fürst, Maximilian J.L.J.,Savino, Simone,Dudek, Hanna M.,Castellanos, J. Rúben Gómez,De Souza, Cora Gutiérrez,Rovida, Stefano,Fraaije, Marco W.,Mattevi, Andrea
supporting information, p. 627 - 630 (2017/05/15)
Regio- and stereoselective Baeyer-Villiger oxidations are difficult to achieve by classical chemical means, particularly when large, functionalized molecules are to be converted. Biocatalysis using flavin-containing Baeyer-Villiger monooxygenases (BVMOs) is a wellestablished tool to address these challenges, but known BVMOs have shortcomings in either stability or substrate selectivity. We characterized a novel BVMO from the thermophilic fungus Thermothelomyces thermophila, determined its three-dimensional structure, and demonstrated its use as a promising biocatalyst. This fungal enzyme displays excellent enantioselectivity, acts on various ketones, and is particularly active on polycyclic molecules. Most notably we observed that the enzyme can perform oxidations on both the A and D ring when converting steroids. These functional properties can be linked to unique structural features, which identify enzymes acting on bulky substrates as a distinct subgroup of the BVMO class.
Exceptional activity of gallium(III) chloride and chlorogallate(III) ionic liquids for Baeyer–Villiger oxidation
Markiton, Magdalena,Chrobok, Anna,Matuszek, Karolina,Seddon, Kenneth R.,Swadzba-Kwasny, Ma?gorzata
, p. 30460 - 30467 (2019/01/14)
Baeyer–Villiger oxidation of cyclic ketones, using H2O2 as the oxidising agent, was systematically studied using a range of metal chlorides in different solvents, and in neat chlorogallate(III) ionic liquids. The extremely high activity of GaCl3 in promoting oxidation with H2O2, irrespective of solvent, was reported for the first time. The activity of all other metal chlorides was strongly solvent-dependent. In particular, AlCl3 was very active in a protic solvent (ethanol), and tin chlorides, SnCl4 and SnCl2, were active in aprotic solvents (toluene and dioxane). In order to eliminate the need for volatile organic solvent, a Lewis acidic chlorogallate(III) ionic liquid was used in the place of GaCl3, which afforded typically 89–94% yields of lactones in 1–120 min, at ambient conditions. Raman and 71Ga NMR spectroscopic studies suggest that the active species, in both GaCl3 and chlorogallate(III) ionic liquid systems, are chlorohydroxygallate(III) anions, [GaCl3OH], which are the products of partial hydrolysis of GaCl3 and chlorogallate(III) anions; therefore, the presence of water is crucial.
