7377-03-9Relevant articles and documents
Influence of octanohydroxamic acid on the association behavior of cationic surfactants: Hydrolytic cleavage of phosphate ester
Satnami, Manmohan L.,Dewangan, Hitesh K.,Kandpal, Neha,Nagwanshi, Rekha,Ghosh, Kallol K.
, p. 805 - 814 (2016)
The surface properties and mixed micellization behavior of cetyltrimethylammonium bromide (CTAB), tetradecyltrimethylammonium bromide (TTAB) and dodecyltrimethylammonium bromide (DTAB) with octanohydroxamic acid (OHA) have been investigated by means of conductivity and surface tension measurements in aqueous solution and borate buffer at 300 K. The critical micelle concentration (cmc), surface properties such as maximum surface access (Γmax), surface pressure at the cmc (Πcmc) and minimum surface area per molecule (Amin) has been determined. The standard Gibbs free energy of micellization (ΔGm0), standard Gibbs free energy of adsorption (ΔGad0), and standard Gibbs free energy of micellization per alkyl chain (ΔGm,tail0) of cationic surfactant with OHA have been evaluated. The fluorescence quenching technique was used to estimate the aggregation number (Nagg) and packing parameter (P) for determining the structural feature of cationic surfactants in the presence of octanohydroxamic acid. The hydrolytic reaction of paraoxon with octanohydroxamic acid was studied under a cationic micellar system by using OHA- at 9.2 pH and 300 K. The variations of surface properties from aqueous medium to the reaction condition have also been discussed. Pseudophase model (PPM) has been fitted for the quantitative treatment of the data.
Alternating Current Electrolysis as Efficient Tool for the Direct Electrochemical Oxidation of Hydroxamic Acids for Acyl Nitroso Diels–Alder Reactions
F?hrmann, Jan,Hilt, Gerhard
supporting information, p. 20313 - 20317 (2021/08/12)
The acyl nitroso Diels–Alder reaction of 1,3-dienes with electrochemically oxidised hydroxamic acids is described. By using alternating current electrolysis, their typical electro-induced decomposition could be suppressed in favour of the 1,2-oxazine cycloaddition products. The reaction was optimised using Design of Experiments (DoE) and a sensitivity test was conducted. A mixture of triethylamine/hexafluoroisopropanol served as supporting electrolyte in dichloromethane, thus giving products of high purity after evaporation of the volatiles without further purification. The optimised reaction conditions were applied to various 1,3-dienes and hydroxamic acids, giving up to 96 % isolated yield.
Preparation process of capryloyl hydroxamic acid
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Paragraph 0034-0042; 0046-0054, (2021/01/30)
The invention relates to the field of chemical synthesis, and particularly discloses a preparation process of capryloyl hydroxamic acid, which comprises the following steps: preparing ethyl n-caprylate, and preparing the capryloyl hydroxamic acid, wherein the ethyl n-caprylate is prepared by the following steps: mixing 1-1.5 kg of n-caprylic acid with 0.35-0.7 kg of ethanol, adding solid superacid, performing heating reflux for 5-7 hours, filtering to obtain precipitate and filtrate, and performing reduced pressure distillation on the filtrate to obtain the ethyl n-caprylate, and the obtainedprecipitate is washed and roasted to obtain the solid superacid, and the solid superacid is recycled to the preparation step of the ethyl n-caprylate for use. By using the solid superacid catalyst, the environmental friendliness of the esterification reaction in the n-capryloyl hydroxamic acid preparation process is improved.
Repurposing the 3-Isocyanobutanoic Acid Adenylation Enzyme SfaB for Versatile Amidation and Thioesterification
Zhu, Mengyi,Wang, Lijuan,He, Jing
supporting information, p. 2030 - 2035 (2020/11/30)
Genome mining of microbial natural products enables chemists not only to discover the bioactive molecules with novel skeletons, but also to identify the enzymes that catalyze diverse chemical reactions. Exploring the substrate promiscuity and catalytic mechanism of those biosynthetic enzymes facilitates the development of potential biocatalysts. SfaB is an acyl adenylate-forming enzyme that adenylates a unique building block, 3-isocyanobutanoic acid, in the biosynthetic pathway of the diisonitrile natural product SF2768 produced by Streptomyces thioluteus, and this AMP-ligase was demonstrated to accept a broad range of short-chain fatty acids (SCFAs). Herein, we repurpose SfaB to catalyze amidation or thioesterification between those SCFAs and various amine or thiol nucleophiles, thereby providing an alternative enzymatic approach to prepare the corresponding amides and thioesters in vitro.
Thioether-Directed NiH-Catalyzed Remote γ-C(sp3)-H Hydroamidation of Alkenes by 1,4,2-Dioxazol-5-ones
Chen, Qishu,Du, Bingnan,Ouyang, Yuxin,Yu, Wing-Yiu
supporting information, p. 14962 - 14968 (2021/09/29)
A NiH-catalyzed thioether-directed cyclometalation strategy is developed to enable remote methylene C-H bond amidation of unactivated alkenes. Due to the preference for five-membered nickelacycle formation, the chain-walking isomerization initiated by the NiH insertion to an alkene can be terminated at the γ-methylene site remote from the alkene moiety. By employing 2,9-dibutyl-1,10-phenanthroline as the ligand and dioxazolones as the reagent, the amidation occurs at the γ-C(sp3)-H bonds to afford the amide products in up to 90% yield (>40 examples) with remarkable regioselectivity (up to 24:1 rr).
METHOD FOR PREPARING N-HYDROXYALKANAMIDE WITH HIGH PURITY
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Paragraph 0062-0076; 0081-0082, (2021/05/04)
The present application relates to a method for preparing N-hydroxyalkaneamide, comprising the steps of: (a) preparing a reaction solution by adding an organic solvent and a surfactant to an aqueous hydroxylamine solution; and (b) adding a carboxylic acid ester to the reaction solution to obtain N-hydroxyalkanamide having 6 to 10 carbon atoms, wherein the organic solvent is insoluble in water.
Preparation process of octanoximic acid (by machine translation)
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Paragraph 0023-0036, (2020/03/09)
The preparation process, comprises the following steps, preparing ethyl acetate, n-octanoic acid ethyl ester and hydroxylamine under the action of sulfuric acid by heating and refluxing :(a) to ;(b) hours to prepare the octanoximic acid, composite catalyst. 30. The preparation method of the octanoximic acid comprises the following steps: sodium acetate and sodium carbonate 60 °C are subjected to hydroxyoximation reaction under the action of a composite catalyst and refluxed 1.5 and 4 hours to prepare the octanoximic acid preparation technology . The technical proposal is as, The method for preparing the octanoximic acid comprises the following steps. 1:0.01. 1:0.03,sup. 1:0.4 .time 1:0.6 10.3.3 (by machine translation)
Preparation method of high-purity capryloyl hydroxamic acid
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Paragraph 0033-0048, (2020/06/16)
The embodiment of the invention relates to a preparation method of high-purity capryloyl hydroxamic acid. The preparation method comprises the following steps: adding sodium sulfide, sodium hydroxideand hydroxylamine hydrochloride into a solvent of a reaction system; adding ethyl n-caprylate into the reaction system for reaction; neutralizing an obtained reaction solution with an acid, filteringto remove salts, removing the solvent in the reaction solution, cleaning, separating and drying to obtain a crude product; wherein sodium sulfide is added before hydroxylamine hydrochloride is added into thereaction system, and the mass ratio of sodium sulfide to ethyl n-caprylate is 0.0015-0.002: 1;the molar ratio of hydroxylamine hydrochloride to ethyl n-caprylate is (1.10-1.15): 1; the reactiontemperature is 45 +/-2 DEG C after ethyl n-caprylate is added. By simultaneously controlling the molar ratio of caprylate to hydroxylamine hydrochloride, the reaction temperature and the addition time and addition amount of Na2S, the purity of the crude product can be 99% on the basis of keeping the yield at 95%.
Method for synthesizing hydroximic acid compound
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Paragraph 0076-0082, (2019/06/13)
The invention discloses a method for synthesizing a hydroximic acid compound. The method comprises the step of subjecting an organic carboxylic acid compound with a structure represented by a formula(I) shown in the description and a hydroxylamine compound with a structure represented by a formula (II) shown in the description to a grinding reaction in the presence of a coupling reagent, therebypreparing the hydroximic acid compound with a structure represented by a formula (III) shown in the description. According to the method, the technical problems that a large amount of organic solventis used, the reaction temperature is high, wastes are plenty, the aftertreatment is complicated, environmental protection is adverse and the like are solved, and the method has the advantages that thesource of the raw materials is wide, the cost is low, the operation is simple, the efficiency is high, the product is easy to separate, the yield is high, industrial production is easy to achieve andthe like.
Preparation method of octanohydroxamic acid
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Paragraph 0022; 0023, (2017/08/29)
The invention discloses a preparation method of octanohydroxamic acid. The preparation method includes: dissolving hydroxylamine hydrochloride into an aqueous alcohol medium, adding n-octoate to form a two-phase reaction system, slowly adding an alkaline solution, and then heating to 25-55 DEG C to perform reaction. The preparation method has the advantages that pure octanohydroxamic acid with purity being above 99% and yield being above 90% can be obtained, and aqueous alcohol medium obtained through centrifugal separation can be reused for multiple times; the method is mild in reaction condition, high in yield, convenient in post-processing, stable in yield, capable of greatly reducing production cost and waste liquid processing cost, convenient to operate, short in reaction time, low in waste liquid amount, economic, practicable, easy in industrial production and effective, and the aqueous alcohol reaction medium can be reused for multiple times.
