97-00-7Relevant academic research and scientific papers
Kinetics and mechanism of p-nitrochlorobenzene nitration with nitric acid
Veretennikov,Lebedev,Tselinskii
, p. 1451 - 1454 (2001)
Kinetics of homogeneous nitration of p-nitrochlorobenzene with 85-95% nitric acid was investigated. An introduction of a nitro group into a chlorobenzene molecule results in 1600 times deceleration of nitration. It was presumed from comparison of kinetic parameters and correlations of log keff for the mono- and dinitration with the acidity functions of nitric acid that the limiting stage in p-nitrochlorobenzene nitration was the transformation of diffusion pairs into reaction products, whereas in chlorobenzene nitration the limiting stage consisted in diffusion pairs formation.
Deaminative chlorination of aminoheterocycles
Ghiazza, Clément,Faber, Teresa,Gómez-Palomino, Alejandro,Cornella, Josep
, p. 78 - 84 (2021/12/23)
Selective modification of heteroatom-containing aromatic structures is in high demand as it permits rapid evaluation of molecular complexity in advanced intermediates. Inspired by the selectivity of deaminases in nature, herein we present a simple methodology that enables the NH2 groups in aminoheterocycles to be conceived as masked modification handles. With the aid of a simple pyrylium reagent and a cheap chloride source, C(sp2)?NH2 can be converted into C(sp2)?Cl bonds. The method is characterized by its wide functional group tolerance and substrate scope, allowing the modification of >20 different classes of heteroaromatic motifs (five- and six-membered heterocycles), bearing numerous sensitive motifs. The facile conversion of NH2 into Cl in a late-stage fashion enables practitioners to apply Sandmeyer- and Vilsmeier-type transforms without the burden of explosive and unsafe diazonium salts, stoichiometric transition metals or highly oxidizing and unselective chlorinating agents. [Figure not available: see fulltext.]
2,2,2-Trifluoroacetaldehyde O-(Aryl)oxime: A Precursor of Trifluoroacetonitrile
Lin, Bo,Yao, Yunfei,Huang, Yangjie,Weng, Zhiqiang
, p. 2055 - 2058 (2022/03/31)
The preparation of 2,2,2-trifluoroacetaldehyde O-(aryl)oxime, a previously inaccessible precursor of trifluoroacetonitrile, via reaction of hydroxylamine and trifluoroacetaldehyde hydrate is reported. This precursor released CF3CN in quantitative yield under mildly basic conditions. The precursor was successfully used in the synthesis of trifluoromethylated oxadiazoles. The facile, cost-effective, scalable, and recyclable procedure makes these trifluoroacetonitrile precursors generally applicable.
Self-powered continuous nitration method and device
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Paragraph 0061-0064, (2021/07/17)
The invention belongs to the technical field of organic synthesis application, and particularly relates to a self-powered continuous nitration method and device. According to the method, a raw material (or a raw material solution) and mixed acid (or nitric acid) are added into a self-powered continuous reactor at the same time, reaction feed liquid continuously and circularly flows, is mixed and reacts in a tube pass through self-propelling force generated by stirring of an impeller, the mass and heat transfer process is completed, and the target requirement is met. According to the invention, the mass transfer and heat transfer efficiency can be improved, the heat exchange and heat transfer capabilities are improved, the reaction time is shortened, the risk degree of art is reduced, the thermal runaway risk is avoided, the reaction safety is improved, and the realization of chemical industry intrinsic safety large scale production is facilitated.
Novel viologen compound and preparation thereof
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Paragraph 0154-0155, (2020/07/23)
The invention relates to novel viologen compounds and a preparation method thereof. Specifically, the invention provides a type of compounds with a structure shown by a formula I. The definitions of the groups are as in the specifications. The compounds of the formula I provided by the invention can be widely applied in the aspects of soft matter material construction, photoelectric materials, and solar cells.
Nitrification method for preparing dinitrochlorobenzene by catalyzing chlorobenzene through ionic liquid
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Paragraph 0029-0071, (2019/04/17)
The invention discloses a nitrification method for preparing dinitrochlorobenzene by catalyzing chlorobenzene through ionic liquid, including the steps of mixing chlorobenzene and a catalyst, heatingto be 50-60 DEG C, mixing with stirring for 2-4 hours to obtain a mixture; respectively adding the mixture and nitric acid solution into a microchannel reactor, performing nitrification in the microchannel reactor, discharging from an outlet, standing for 24 hours, extracting subnatant, and then washing, neutralizing and drying the subnatant to obtain dinitrochlorobenzene. The method is green andenvironmentally friendly as generating of a great quantity of waste acid is avoided in production; reaction in the method has high selectivity and high yield, and 2,4-dinitrochlorobenzene prepared bythe method has high purity.
Preparation method of nitrification organic matter and prepared nitrification organic matter
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Paragraph 0097-0100, (2019/07/29)
The invention discloses a preparation method of nitrification organic matter and the prepared nitrification organic matter, and relates to the technical field of organic synthesis. The preparation method of the nitrification organic substance comprises the following steps: introducing a nitrification acid liquid and molten-state organic matter to be nitrified into a microchannel reactor, and performing a reaction, wherein the organic matter to be nitrified is solid at normal temperature, and solidification and/or dissolution in the nitrification acid liquid does not occur in the organic matterto be nitrified after the organic matter to be nitrified is introduced into the microchannel reactor. According to the preparation method of the nitrification organic matter provided by the invention, the nitrification organic matter prepared by the method has a very good yield and purity without a solvent removal post-treatment process; in the whole process, no solvent participates in the reaction, so that the post-treatment process of solvent removal is avoided; and the method has high safety in the whole reaction process, adopts automation control, has high production efficiency and a greatly-improved production environment, and has larger industrial application value.
NITRATION OF AROMATIC COMPOUNDS
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Paragraph 0051, (2016/08/17)
The present invention provides a process for nitrating aromatic compounds without the need for a solid catalyst and/or any organic solvents and/or any other additives. A typical process includes combining or admixing a nitric acid and an anhydride compound under conditions sufficient to produce a reactive intermediate. The aromatic compound to be nitrated is then added to this reactive intermediate to produce a nitroaromatic compound. The nitroaromatic compound can be substituted with one or more, typically, one to three, and often one or two nitrate (-NO2) groups.
The novel usage of thiourea nitrate in aryl nitration
Meng, Ge,Zheng, Mei-Lin,Zheng, A-Qun,Wang, Mei,Shi, Juan
, p. 87 - 89 (2014/02/14)
Thiourea nitrate (TN) was easily prepared from thiourea and nitric acid to explore its use as a new nitration reagent. Nitrations of various aromatic compounds utilizing TN in concentrated sulfuric acid were studied. TN could convert aromatic compounds to the corresponding nitrated derivatives with various abnormal yields under mild conditions. The results suggested that the reaction mechanism might be different from those of traditional nitration reagents.
Application of screening experimental designs to assess chromatographic isotope effect upon isotope-coded derivatization for quantitative liquid chromatography-mass spectrometry
Szarka, Szabolcs,Prokai-Tatrai, Katalin,Prokai, Laszlo
, p. 7033 - 7040 (2014/08/05)
Isotope effect may cause partial chromatographic separation of labeled (heavy) and unlabeled (light) isotopologue pairs. Together with a simultaneous matrix effect, this could lead to unacceptable accuracy in quantitative liquid chromatography-mass spectrometry assays, especially when electrospray ionization is used. Four biologically relevant reactive aldehydes (acrolein, malondialdehyde, 4-hydroxy-2-nonenal, and 4-oxo-2-nonenal) were derivatized with light or heavy (d3-, 13C6-, 15N2-, or 15N4-labeled) 2,4-dinitrophenylhydrazine and used as model compounds to evaluate chromatographic isotope effects. For comprehensive assessment of retention time differences between light/heavy pairs under various gradient reversed-phase liquid chromatography conditions, major chromatographic parameters (stationary phase, mobile phase pH, temperature, organic solvent, and gradient slope) and different isotope labelings were addressed by multiple-factor screening using experimental designs that included both asymmetrical (Addelman) and Plackett-Burman schemes followed by statistical evaluations. Results confirmed that the most effective approach to avoid chromatographic isotope effect is the use of 15N or 13C labeling instead of deuterium labeling, while chromatographic parameters had no general influence. Comparison of the alternate isotope-coded derivatization assay (AIDA) using deuterium versus 15N labeling gave unacceptable differences (>15%) upon quantifying some of the model aldehydes from biological matrixes. On the basis of our results, we recommend the modification of the AIDA protocol by replacing d 3-2,4-dinitrophenylhydrazine with 15N- or 13C-labeled derivatizing reagent to avoid possible unfavorable consequences of chromatographic isotope effects.
