550-60-7Relevant articles and documents
Specific para-hydroxylation of nitronaphthalenes with cumene hydroperoxide in basic aqueous media
Zhu, Lei,Zhang, Lin-Hua
, p. 3519 - 3522 (2000)
A synthetic method for specific para-hydroxylation of nitroarenes has been developed. The reaction of nitronaphthalenes with cumeme hydroperoxide in basic aqueous media produces exclusively para-hydroxy nitronaphthalenes in good yield. The selectivity of ortho and para hydroxylation is mediated by water content. The rationale for water-controlled orientation of hydroxylation has been briefly discussed. (C) 2000 Elsevier Science Ltd.
Light-Controlled Tyrosine Nitration of Proteins
Long, Tengfang,Liu, Lei,Tao, Youqi,Zhang, Wanli,Quan, Jiale,Zheng, Jie,Hegemann, Julian D.,Uesugi, Motonari,Yao, Wenbing,Tian, Hong,Wang, Huan
supporting information, p. 13414 - 13422 (2021/05/12)
Tyrosine nitration of proteins is one of the most important oxidative post-translational modifications in vivo. A major obstacle for its biochemical and physiological studies is the lack of efficient and chemoselective protein tyrosine nitration reagents. Herein, we report a generalizable strategy for light-controlled protein tyrosine nitration by employing biocompatible dinitroimidazole reagents. Upon 390 nm irradiation, dinitroimidazoles efficiently convert tyrosine residues into 3-nitrotyrosine residues in peptides and proteins with fast kinetics and high chemoselectivity under neutral aqueous buffer conditions. The incorporation of 3-nitrotyrosine residues enhances the thermostability of lasso peptide natural products and endows murine tumor necrosis factor-α with strong immunogenicity to break self-tolerance. The light-controlled time resolution of this method allows the investigation of the impact of tyrosine nitration on the self-assembly behavior of α-synuclein.
Method for preparing 6-nitro-2-diazo-1-naphthol-4-sulfonic acid hydrate
-
Paragraph 0008; 0032-0034; 0041-0043, (2020/06/17)
The invention discloses a method for preparing 6-nitro-2-diazo-1-naphthol-4-sulfonic acid hydrate. The method comprises the following steps: carrying out a nitrosation reaction on 2-naphthol serving as a raw material, sodium nitrite and dilute sulfuric acid in a tubular reactor to generate 1-nitroso-2-naphthol, carrying out catalytic hydrogenation on the 1-nitroso-2-naphthol and hydrogen in a Raney nickel immobilized fixed bed reactor to generate 1-amino-2-naphthol, carrying out sulfonation diazotization cyclization on 1-amino-2-naphthol and nitrosyl sulfuric acid in the tubular reactor, and nitrifying with nitric acid to obtain the final product 6-nitro-2-diazo-1-naphthol-4-sulfonic acid hydrate. According to the novel synthesis method of the 6-nitro-2-diazo-1-naphthol-4-sulfonic acid hydrate, hydrogen is used for reduction in the route, nitrosyl sulfuric acid is used for sulfonation diazotization cyclization, so the problem that a large amount of solid waste is generated in a traditional route is avoided, the atom utilization rate is high, the yield is increased, the safety coefficient is increased by using a tubular process, and the method is suitable for industrial production.
Ruthenium-Catalyzed Tandem Carbene/Alkyne Metathesis/N-H Insertion: Synthesis of Benzofused Six-Membered Azaheterocycles
Padín, Damián,Saá, Carlos,Varela, Jesús A.
supporting information, (2020/03/30)
The Cp*RuCl-based catalyst enables expedient access to a variety of benzofused six-membered azaheterocycles from unprotected o-alkynylanilines and trimethylsilyldiazomethane through an unprecedent tandem carbene/alkyne metathesis/N-H insertion reaction. The transformation takes place under mild reaction conditions (room temperature, 15 min) and with excellent functional group tolerance. The synthetic utility of the final products and a mechanistic rationale are also discussed.
Ring-Fused 1,4-Dihydro[1,2,4]triazin-4-yls through Photocyclization
Bartos, Paulina,Kaszyński, Piotr,Young, Victor G.
supporting information, (2020/05/22)
Halogen lamp irradiation of benzo[e][1,2,4]triazines 2[X] in CH2Cl2 solutions leads to planar ring-fused 1,4-dihydro[1,2,4]triazin-4-yl radicals 1 through a novel, potentially general, cyclization mechanism. The scope and efficiency of the method were established for unsubstituted and ortho-substituted (X = NH2, Br, NO2) phenoxy, naphthyloxy, and quinolinoxy derivatives 2[X]. The regioselectivity of 2[X] photocyclization was rationalized with DFT computational methods. Radicals 1 were characterized by spectroscopic (UV-vis, EPR), electrochemical, and XRD methods.
Iodine(III)-Catalyzed Electrophilic Nitration of Phenols via Non-Br?nsted Acidic NO2+ Generation
Juárez-Ornelas, Kevin A.,Jiménez-Halla, J. Oscar C.,Kato, Terumasa,Solorio-Alvarado, César R.,Maruoka, Keiji
supporting information, p. 1315 - 1319 (2019/03/07)
The first catalytic procedure for the electrophilic nitration of phenols was developed using iodosylbenzene as an organocatalyst based on iodine(III) and aluminum nitrate as a nitro group source. This atom-economic protocol occurs under mild, non-Br?nsted acidic and open-flask reaction conditions with a broad functional-group tolerance including several heterocycles. Density functional theory (DFT) calculations at the (SMD:MeCN)Mo8-HX/(LANLo8+f,6-311+G) level indicated that the reaction proceeds through a cationic pathway that efficiently generates the NO2+ ion, which is the nitrating species under neutral conditions.
3-(Ethoxycarbonyl)-1-(5-methyl-5-(nitrosooxy)hexyl)pyridin-1-ium cation: A green alternative to tert-butyl nitrite for synthesis of nitro-group-containing arenes and drugs at room temperature
Chaudhary, Renu,Natarajan, Palani,Rani, Neetu,Sakshi,Venugopalan, Paloth
supporting information, (2019/12/30)
Due to their remarkable properties, task-specific ionic liquids have turned out to be progressively popular over the last few years in the field of green organic synthesis. Herein, for the first time, we report that a new task-specific nitrite-based ionic liquid such as 3-(ethoxycarbonyl)-1-(5-methyl-5-(nitrosooxy)hexyl)pyridin-1-ium bis(trifluoromethanesulfonyl)imides (TS-N-IL) derived from biodegradable ethyl nicotinate indeed acted as an efficient and eco-friendly reagent for the synthesis of highly valuable nitroaromatic compounds and drugs including nitroxynil, tolcapone, niclofolan, flutamide, niclosamide and nitrazepam. The bridging of an ionic liquid with nitrite group not only increases the yield and rate of direct C[sbnd]N bond formation reaction but also allows easy product separation and recyclability of a byproduct. Nonvolatile nature, easy synthesis, merely stoichiometric need and mildness are a portion of the extra focal points of TS-N-IL while contrasted with tert-butyl nitrite an outstanding and highly-flammable reagent utilized largely in organic synthesis.
2-Methyl-1,3-disulfoimidazolium polyoxometalate hybrid catalytic systems as equivalent safer alternatives to concentrated sulfuric acid in nitration of aromatic compounds
Saikia, Susmita,Borah, Ruli
, (2019/08/20)
Ionic liquid-derived polyoxometalate salts [mdsim]3[PM12O40] (where M?=?W and Mo) of two heteropolyacids H3PW12O40.nH2O and H3PMo12O40.nH2O were synthesized using 2-methyl-1,3-disulfoimidazolium chloride ([mdsim][Cl]) ionic liquid and the corresponding heteropolyacids. Three equivalents of [mdsim][Cl] were treated with the respective Keggin-structured heteropolyacids (one equivalent) in aqueous medium at room temperature to afford the water-stable ionic polyoxometalates as acidic solids. They were completely characterized using spectroscopic and other analytical techniques including thermal analysis and Hammett acidity studies. The inherent Br?nsted acidic properties of ─SO3H group of these polyoxometalate salts were studied for the nitration of aromatic compounds with 69% HNO3 at normal temperature and 80°C without use of any external concentrated sulfuric acid. These strongly acidic polyoxometalates display good recyclability and efficient reusability.
Silica-supported perchloric acid and potassium bisulfate as reusable green catalysts for nitration of aromatics under solvent-free microwave conditions
Kumar, M. Satish,Sriram, Y. Hemanth,Venkateswarlu,Rajanna,Sudhakar, M. Sai,Venkanna, Purugula,Saiprakash
supporting information, p. 59 - 67 (2017/12/26)
Silica-supported perchloric acid and bisulfate (SiO2/HClO4 and SiO2/KHSO4) have been developed as reusable green catalysts for nitration of aromatic compounds using NaNO2 in acetonitrile medium under conventional and solvent-free microwave conditions. The reaction times under microwave irradiation are significantly shorter than conventional method even though the yields obtained in microwave-assisted reactions are comparable with those obtained under reflux conditions.
Preparation method of 1-nitro-2-naphthol derivative
-
Paragraph 0031-0034, (2017/08/30)
The invention belongs to the field of organic synthesis and in particular relates to a preparation method of a 1-nitro-2-naphthol derivative. The preparation method comprises the following steps: adding a 2-naphthol derivative shown as a formula I-1, tert-butyl nitrite and a certain amount of water into a dry reactor; adding a certain amount of an organic solvent and stirring at room temperature (commonly referring to 20 DEG C to 25 DEG C) for a period of time; after reacting, filtering an reaction solution through a glass dropper filled with silica gel; washing a filter cake with ethyl acetate; spinning and drying filtrate; carrying out silica gel column chromatography separation to obtain a target product with a formula I. A reaction formula can be shown in the description.