4835-90-9Relevant academic research and scientific papers
Liquid-phase heterogeneous oxidation of hydroxypivalaldehyde with oxygen in alkaline aqueous solution in the presence of supported palladium catalyst
Zhizhkun,Chernaya,Trusov
, p. 942 - 945 (2002)
The kinetics of a model reaction of hydroxypivalaldehyde oxidation with molecular oxygen in alkaline aqueous solution in the presence of 4% Pd/Al 2O3 was studied with the aim of searching for promising heterogeneous catalysts for D-g
Pivalic Acid as Combined Buffer and Scavenger for Studies of Cloud Water Chemistry with Pulse Radiolysis
Nauser, Thomas,Buehler, Rolf E.
, p. 3651 - 3656 (1994)
The reactions of cloud water with transition-metal ions may be studied using pivalic acid as buffer and OH(1.) scavenger.Commonly used phosphate buffers form strong complexes that may have an important effect on reaction kinetics.Low solubility products limit transition-metal ion concentrations to very low levels (micromolar).With pivalic acid as buffer, we can increase the Cu(II) concentration typically by a factor of 340.At the same time better buffer characteristics and less complex formation is achieved.The scavenger efficiency equals that of tert-butyl alcohol.The rate data and the spectra of pivalic acid radicals have been measured in N2O-saturated solutions of pivalic acid.The acid constant was found to be 4.9 +/- 0.1.The rate constants for the reaction of OH(1.) with pivalic acid have been re-evaluated: k = (7+/-2)E8 dm3 mol-1 s-1 and k = 6.5E8 dm3 mol-1 s-1.The importance of including reactions like H(1.) + (1.)CH2(CH3)2CCO2H in the reaction model is shown.The rate constants for the recombination of pivalic acid radicals are: k = (7+/-1)E8 dm3 mol-1 s-1, k = (7+/-3)E8 dm3 mol-1 s-1 and k = (3.7+/-0.4)E8 dm3 mol-1 s-1.
Pd(II)-Catalyzed Chemoselective Acetoxylation of C(sp2)-H and C(sp3)-H Bonds in Tertiary Amides
Vijaykumar, Muniyappa,Punji, Benudhar
, p. 8172 - 8181 (2021)
Palladium-catalyzed chemoselective C(sp2)-H and C(sp3)-H acetoxylation of synthetically useful tertiary amides is reported under relatively mild reaction conditions. This protocol proceeds through the assistance of a weakly coordinated directing group (Ca? O) and requires low catalyst (1.0 mol %) loading. Diverse functionalities, such as C(sp2)-Cl, C(sp3)-Cl,-CF3,-COOEt, and-NO2 groups, including morpholinyl, piperazinyl, and pyrrolidinyl heterocycles, are compatible under the reaction conditions. Further functionalization of this protocol is demonstrated by hydrolysis to alcohols, alcohol-acids, as well as reduction to tertiary amines. A preliminary kinetic isotope effect study supported the rate-limiting C-H bond activation process.
Chemoenzymatic Production of Enantiocomplementary 2-Substituted 3-Hydroxycarboxylic Acids from l-α-Amino Acids
Pickl, Mathias,Marín-Valls, Roser,Joglar, Jesús,Bujons, Jordi,Clapés, Pere
, p. 2866 - 2876 (2021/04/14)
A two-enzyme cascade reaction plus in situ oxidative decarboxylation for the transformation of readily available canonical and non-canonical l-α-amino acids into 2-substituted 3-hydroxycarboxylic acid derivatives is described. The biocatalytic cascade consisted of an oxidative deamination of l-α-amino acids by an l-α-amino acid deaminase from Cosenzaea myxofaciens, rendering 2-oxoacid intermediates, with an ensuing aldol addition reaction to formaldehyde, catalyzed by metal-dependent (R)- or (S)-selective carboligases namely 2-oxo-3-deoxy-l-rhamnonate aldolase (YfaU) and ketopantoate hydroxymethyltransferase (KPHMT), respectively, furnishing 3-substituted 4-hydroxy-2-oxoacids. The overall substrate conversion was optimized by balancing biocatalyst loading and amino acid and formaldehyde concentrations, yielding 36–98% aldol adduct formation and 91–98% ee for each enantiomer. Subsequent in situ follow-up chemistry via hydrogen peroxide-driven oxidative decarboxylation afforded the corresponding 2-substituted 3-hydroxycarboxylic acid derivatives. (Figure presented.).
Design and Synthesis of Novel N-(2-aminophenyl)benzamide Derivatives as Histone Deacetylase Inhibitors and Their Antitumor Activity Study
La, Minh Thanh,Jeong, Byung-Hoon,Kim, Hee-Kwon
supporting information, p. 740 - 743 (2021/03/16)
Histone deacetylases (HDACs) are promising therapeutic targets for cancer therapy because inhibition of HDACs triggers growth arrest or apoptosis of tumor cells. In the present study, a new series of fluorinated N-(2-aminophenyl)benzamide derivatives were synthesized to investigate potential inhibition of HDACs and associated anticancer activity. Among the synthesized derivatives, compound 24a showed potent inhibitory activity of HDACs and higher antitumor efficacy in human cancer cell lines (HCT-116, MCF-7, and A549) compared with SAHA. Moreover, animal studies demonstrated that compound 24a showed potent in vivo antitumor efficacy in an HCT-116 colon cancer xenograft mouse model.
Aerobic Aliphatic Hydroxylation Reactions by Copper Complexes: A Simple Clip-and-Cleave Concept
Becker, Jonathan,Zhyhadlo, Yevheniia Y.,Butova, Ekaterina D.,Fokin, Andrey A.,Schreiner, Peter R.,F?rster, Moritz,Holthausen, Max C.,Specht, Pascal,Schindler, Siegfried
, p. 15543 - 15549 (2018/09/21)
A simple imine clip-and-cleave concept has been developed for the selective hydroxylation of non-activated CH bonds in aliphatic aldehydes with dioxygen through a copper complex. The synthetic protocol involves reaction of a substrate aldehyde with N,N-diethyl-ethylendiamine to give the corresponding imine, which is used as a bidentate donor ligand forming a copper(I) complex with [Cu(CH3CN)4][CF3SO3]. After exposure of the reaction mixture to dioxygen acidic cleavage and aqueous workup liberates the corresponding β-hydroxylated aldehyde. The concept for the hydroxylation of trimethylacetaldehyde as well as adamantane and diamantane 1-carbaldehydes was investigated and the corresponding β-hydroxy aldehydes were obtained with high selectivities. The results of low temperature stopped-flow measurements indicate the formation of a bis(μ-oxido)dicopper complex as reactive intermediate. According to density functional theory (DFT, RI-BLYP-D3/def2-TZVP(SDD)/ COSMO(CH2Cl2)//RI-PBE-D3/def2-TZVP(SDD)) computations CH bonds suitably predisposed to the [Cu2O2]2+ core undergo hydroxylation in a concerted step with particularly low activation barriers, which explains the experimentally observed regioselectivities.
Synthesis method of 2,2-dimethyl-3-hydroxypropionic acid
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Paragraph 0030; 0031; 0034; 0035, (2017/03/14)
The invention discloses a synthesis method of 2,2-dimethyl-3-hydroxypropionic acid. With isobutyraldehyde and formaldehyde as the raw materials, 2,2-dimethyl-3-hydroxypropionic acid is directly prepared through aldol reaction and disproportionation and oxidation reaction, a catalyst composed of aluminium oxide and manganese oxide is added in the aldol reaction, and a catalyst formed by mixing bismuth oxide with aluminium oxide is added in the disproportionation and oxidation reaction; meanwhile, the reaction conditions are optimized, the excessive consumption of sodium hydroxide is lowered, reaction time is shortened, reaction energy consumption is lowered, reaction yield is improved, and high economic benefits are achieved.
Preparation method of hydroxypivalic acid
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Paragraph 0052; 0053; 0057, (2017/01/02)
The invention provides a preparation method of hydroxypivalic acid. The preparation method comprises the following steps: (1) adding a sodium carbonate water solution into a sodium polystyrenesulfonate water solution, stirring, regulating the pH value, adding a barium chloride water solution, stirring, standing, taking out, filtering, washing, and drying to obtain barium carbonate microspheres; (2) adding the barium carbonate microspheres into absolute ethyl alcohol, carrying out ultrasonic dispersion, adding CTAB, continuing to carry out ultrasonic dispersion to obtain a barium carbonate microsphere solution, dropwise adding a hydrated silica solution, carrying out magnetic stirring, standing, carrying out centrifuging, washing, drying, and calcining so as to obtain a BaO/SiO2 core-shell microsphere catalyst; (3) adding a formaldehyde water solution and triethylamine into a four-mouth flask, heating in a water bath, dropwise adding isobutyraldehyde, and carrying out reduced pressure distillation on a reaction liquid, so as to obtain hydroxyl pivaldehyde; and (4) adding hydroxyl pivaldehyde and a sodium hydroxide solution into the four-mouth flask, carrying out heating reflux, adding water and a catalyst, heating while stirring, carrying out suction filtration on the reaction liquid, concentrating a filtrate, regulating the pH value, carrying out extraction, and standing until crystals are separated. The preparation method has the beneficial effects of relatively high benefit, relatively low cost and mild condition.
Method for preparing hydroxypivalic acid by catalytic oxidation of phosphotungstic acid
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Paragraph 0042; 0043, (2016/12/01)
The invention discloses a method for preparing hydroxypivalic acid by catalytic oxidation of phosphotungstic acid and belongs to the technical field of chemical industry.The method comprises: subjecting isobutyraldehyde and formaldehyde to aldol condensation under the catalytic action of triethylamine; in an existing production method of hydroxypivalic acid, the shortest oxidation time takes 9 hours; the process used herein takes only 4 hours to produce a product; in the existing production method of hydroxypivalic acid, highest product yield is about 75%, and the yield of the product of the invention is up to 80-85%.The defects that an original process produces many byproducts and the byproducts are difficult to separate are overcome, product purity is effectively improved, and the technical process is simplified; a catalyst used herein is reusable, the activity of the catalyst decreases at low speed, energy consumption of the oxidation process is low, and production cost is thus reduced.
Gold(I)/copper(II)-cocatalyzed tandem cyclization/semipinacol reaction: Construction of 6-Aza/Oxa-Spiro[4.5]decane skeletons and formal synthesis of (±)-halichlorine
Zhu, Dao-Yong,Zhang, Zhen,Mou, Xue-Qing,Tu, Yong-Qiang,Zhang, Fu-Min,Peng, Jin-Bao,Wang, Shao-Hua,Zhang, Shu-Yu
, p. 747 - 752 (2015/03/18)
A simple and efficient strategy for the construction of 6-aza/oxa-spiro[4.5]decane skeletons under the cocatalysis of gold(I)/copper(II) was developed, and its potential utility was demonstrated by a formal synthesis of the biologically active marine alkaloid (±)-halichlorine.
