55-22-1Relevant articles and documents
STABILITY OF WATER-SOLUBLE VITAMINS AND COENZYMES. VIII. KINETICS OF ACID HYDROLYSIS OF NICOTINOYL-γ-AMINOBUTYRIC ACID
Kozlov, E. I.,L'vova, M. Sh.,Garber, N. I.
, p. 328 - 333 (1988)
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Continuous flow metal-free oxidation of picolines using air
Hamano, Masaya,Nagy, Kevin D.,Jensen, Klavs F.
, p. 2086 - 2088 (2012)
The metal free, direct oxidation of 2-, 3-, and 4-picoline to the corresponding carboxylic acid using either oxygen or air has been developed under continuous flow conditions. Complete conversion for all three substrates was obtained at moderate temperatures and pressures within minutes.
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Trubnikov et al.
, (1968)
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Bartok et al.
, p. 410 (1963)
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v.Euler,Hasselquist
, p. 439,445 (1958)
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Toma,Malin
, p. 288 (1975)
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Decoration of copper foam with Ni nanorods and copper oxide nanosheets to produce a high-stability electrocatalyst for the reduction of CO2: Characterization of the electrosynthesis of isonicotinic acid
Mohammadzadeh, Safoora,Zare, Hamid R.,Khoshro, Hossein
, p. 678 - 685 (2019)
CuO–Cu2O (CuxO) nanosheets were coated on a copper foam substrate by the electrochemical anodization method in an alkaline solution. Constant current coulometry was performed to electrodeposit Ni nanorods on the surface of a Cu/CuxO electrode. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) proved that the copper oxide nanosheets were anchored on the copper foam substrate and modified by Ni nanorods (Cu/CuxO/Ni). The process took place via a facile and inexpensive electrodeposition method. As the results indicate, owing to the synergistic effect of adjacent CuxO and Ni sites, a Cu/CuxO/Ni electrode has a very good and stable electrocatalytic activity to reduce CO2. As tested in this study, the product of the electrocatalytic reduction of CO2 (i.e. activated CO2, or CO2 ??) can be used for the electrocarboxylation of pyridine in mild conditions. Once an electron is transferred from CO2 ?? to pyridine, a pyridine radical anion is formed. Based on the EC'C′CC mechanism, this radical anion reacts with CO2 ?? and produces isonicotinic acid as the main product. In addition, two pyridine radical anions react together and produce a 4,4′-bipyridine dimer. The high stability of the electrocatalyst during the electrolysis process and the simplicity of the workup make the proposed modified electrode appropriate for the electrosynthesis of some organic compounds.
Kinetics of the highly selective liquid-phase oxidation of side chain alkyl groups in 2-methylpyrazine and picolines by selenium dioxide
Mukhopadhyay, Sudip,Chandalia, Sampatraj B.
, p. 455 - 459 (1999)
Kinetics of the liquid-phase oxidation of alkyl groups in 2-methylpyrazine and picolines with selenium dioxide at moderate conditions were studied. Thus, 2-methylpyrazine was oxidized to pyrazinoic acid with selenium dioxide in pyridine at 115 °C with 99% selectivity at a 2-methylpyrazine conversion of 100% in 8 h. It was deduced that the reaction follows secondorder kinetics and the activation energy was found to be 35 kcal/mol. The same reaction-scheme was found to hold for picolines oxidation to obtain picolinic acids. The byproduct selenium, formed in the reaction, was converted back to selenium dioxide by nitric acid oxidation with 100% selectivity.
Oxidation of Antitubercular Drug Isoniazid by a Lipopathic Oxidant, Cetyltrimethylammonium Dichromate: A Mechanistic Study
Garnayak, Sarita,Patel, Sabita
, p. 32 - 44 (2016)
The oxidation of an antitubercular drug isoniazid by a lipopathic oxidant cetyltrimethylammonium dichromate (CTADC) in a nonpolar medium generates isonicotinic acid both in the presence and the absence of acetic acid. The conventional UV–vis spectrophotometric method is used to study the reaction kinetics. The occurrence of the Michaelis–Menten–type kinetics with respect to isoniazid confirms the binding of oxidant and substrate to form a complex before the rate-determining step. The existence of the inverse solvent kinetic isotope effect, k(H2O)/ k(D2O) = 0.7, in an acid-catalyzed reaction proposes a multistep reaction mechanism. A decrease in the rate constant with an increase in [CTADC] reveals the formation of reverse micellar–type aggregates of CTADC in nonpolar solvents. In the presence of different ionic and nonionic surfactants, CTADC forms mixed aggregates and controls the reaction due to the charge on the interface and also due to partition of oxidant and substrate in two different domains. High negative entropy of activation (ΔS? = –145 and –159 J K?1 mol?1 in the absence and presence of acetic acid) proposes a more ordered and highly solvated transition state than the reactants. Furthermore, the solvent polarity-reactivity relationship reveals (i) the presence of less polar and less ionic transition state compared to the reactants during the oxidation, (ii) differential contribution from nonpolar and dipolar aprotic solvents toward the reaction process, and (iii) the existence of polarity/hydrophobic switch at log P = 0.73. A suitable mechanism has been proposed on the basis of experimental results. These results may provide insight into the mechanism of isoniazid oxidation in hydrophobic environment and may assist in understanding the drug resistance in different location.
Oxidation of isoniazid by N-haloarenesulfonamidates in alkaline medium: A kinetic and mechanistic study
Puttaswamy,Anuradha,Ramachandrappa,Made Gowda
, p. 221 - 230 (2000)
The kinetics of oxidation of Isoniazid (INH) by sodium N-haloarenesulfonamidates, chloramine-T (CAT), bromamine-T (BAT), chloramine-B (CAB), and bromamine-B (BAB), has been studied in alkaline medium at 303 K. The oxidation reaction follows identical kinetics with a first-order dependence on each [oxidant] and [INH] and an inverse fractional-order on [OH-]. Addition of the reaction product (p-toluenesulfonamide or benzenesulfonamide) had no significant effect on the reaction rate. Variation of ionic strength and addition of halide ions have no influence on the rate. There is a negative effect of dielectric constant of the solvent. Studies of solvent isotope effects using D2O showed a retardation of rate in the heavier medium. The reaction was studied at different temperatures, and activation parameters have been computed from the Arrhenius and Eyring plots. Isonicotinic acid was identified as the oxidation product by GC-MS. A two-pathway mechanism is proposed in which RNHX and the anion RNX- interact with the substrate in the rate-limiting steps. The mechanism proposed and the derived rate laws are consistent with the observed kinetics. The rate of oxidation of INH increases in the order: BAT>BAB>CAT>CAB. This effect is mainly due to electronic factors.
An ESIPT-based colorimetric and fluorescent probe with large Stokes shift for the sensitive detection of hypochlorous acid and its bioimaging in cells
Ren, Haixian,Huo, Fangjun,Yin, Caixia
, p. 4724 - 4728 (2021)
Hypochlorous acid (HOCl), with a low physiological concentration, plays a vital role in killing the pathogens and anti-inflammation in the human immune system. Deviation from the normal concentration is directly related to the inflammation-associated diseases and even cancer. Thus, it is necessary to sensitively detect the tiny concentration changes of HOCl. However, few of the reported probes could practically work well due to small Stokes shift, high detection of limits, and low SNR. In this study, HBT (2-(2′-Hydroxyphenyl)benzothiazole) was used as the candidate for the ESIPT-based fluorophore and connected to pyridinevia“CC” bonds. The “CC” bonds are the reaction site for HOCl and are activated by the strong electron-withdrawing CN group located on the double-bond carbon atom, resulting in a high sensitivity towards HOCl. Thereby, the probe's emission shifted effectively to the red channel avoiding the interference from biological autofluorescence. The excellent response of the probeJBDtowards HOCl enables it to detect endogenous hypochlorous acid in the cells and provides an ideal molecular tool for exploring the mechanism of hypochlorous acid in oxidative stress and its immune role.
SYNTHESIS OF PYRIDYL(TRICHLOROMETHYL)CARBINOLS UNDER INTERPHASE-CATALYSIS CONDITIONS
Iovel', I. G.,Gol'dberg, Yu. Sh.,Gaukhman, A. P.,Shimanskaya, M. V.
, p. 40 - 43 (1990)
The corresponding pyridyl(trichloromethyl)carbinols were obtained by reactions of 2- and 3-formylpyridine and 6-methyl-2-formylpyridine with chloroform in the presence of aqueous or solid alkali and an interphase catalyst.It is shown that carrying out the reaction in a liquid-solid system is more efficient than in a liquid-liquid system.
MOF-Zn-NHC as an efficient N-heterocyclic carbene catalyst for aerobic oxidation of aldehydes to their corresponding carboxylic acids: Via a cooperative geminal anomeric based oxidation
Babaee, Saeed,Zarei, Mahmoud,Zolfigol, Mohammad Ali
, p. 36230 - 36236 (2021/12/02)
As an efficient heterogenous N-heterocyclic carbene (NHC) catalyst, MOF-Zn-NHC was used in the aerobic oxidation of aryl aldehydes to their corresponding carbocyclic acids via an anomeric based oxidation. Features such as mild reaction conditions and no need for a co-catalyst or oxidative reagent can be considered as the major advantages of the presented method in this study. This journal is
Photo-induced deep aerobic oxidation of alkyl aromatics
Wang, Chang-Cheng,Zhang, Guo-Xiang,Zuo, Zhi-Wei,Zeng, Rong,Zhai, Dan-Dan,Liu, Feng,Shi, Zhang-Jie
, p. 1487 - 1492 (2021/07/10)
Oxidation is a major chemical process to produce oxygenated chemicals in both nature and the chemical industry. Presently, the industrial manufacture of benzoic acids and benzene polycarboxylic acids (BPCAs) is mainly based on the deep oxidation of polyalkyl benzene, which is somewhat suffering from environmental and economical disadvantage due to the formation of ozone-depleting MeBr and corrosion hazards of production equipment. In this report, photo-induced deep aerobic oxidation of (poly)alkyl benzene to benzene (poly)carboxylic acids was developed. CeCl3 was proved to be an efficient HAT (hydrogen atom transfer) catalyst in the presence of alcohol as both hydrogen and electron shuttle. Dioxygen (O2) was found as a sole terminal oxidant. In most cases, pure products were easily isolated by simple filtration, implying large-scale implementation advantages. The reaction provides an ideal protocol to produce valuable fine chemicals from naturally abundant petroleum feedstocks. [Figure not available: see fulltext.].