121-87-9Relevant academic research and scientific papers
Kinetic study and mechanism of Niclosamide degradation
Zaazaa, Hala E.,Abdelrahman, Maha M.,Ali, Nouruddin W.,Magdy, Maimana A.,Abdelkawy
, p. 655 - 662 (2014)
A spectrophotometric kinetic study of Niclosamide alkaline degradation as a function of drug concentration, alkaline concentration and temperature has been established utilizing double divisor-ratio spectra spectrophotometric method. The developed method allowed determination of Niclosamide in presence of its alkaline degradation products; namely; 2-chloro-4-nitro aniline (DEG I) and 5-chloro salicylic acid (DEG II) with characterization of its degradation mechanism. It was found that degradation kinetic of Niclosamide followed pseudo-first order under the established experimental conditions with a degradation rate constant (k) of 0.0829 mol/h and half life (t1/2) of 8.35 h. The overall degradation rate constant as a function of the temperature under the given conditions obeyed Arrhenius equation where the activation energy was calculated to be 3.41 kcal/mol.
Practical and efficient chlorination of deactivated anilines and anilides with NCS in 2-propanol
Zanka, Atsuhiko,Kubota, Ariyoshi
, p. 1984 - 1986 (1999)
Deactivated anilines and anilides were efficiently monochlorinated with NCS in 2-propanol. The described method was applicable to a large scale synthesis.
Sodium lauryl sulfate-catalyzed oxidative chlorination of aromatic compounds
Mahajan, Tanu,Kumar, Lalit,Dwivedi, K.,Agarwal, D. D.
, p. 3655 - 3663,9 (2012)
Chlorination of commercially important aromatic compounds using sodium chloride as chlorine source and sodium periodate as oxidant in acidic medium catalyzed by sodium lauryl sulfate (SLS) led to the chloro-substituted aromatics in good yields and purity. Addition of sodium lauryl sulfate led to increased chlorination rate, better yield, excellent purity, and better quality of end product. The advantages of the present method are greater yield, excellent purity, and shorter reaction time at room temperature. Also dichlorinated product can be obtained by increasing the amount of sodium chloride and sodium periodate at slightly higher temperature (40C).
Activator free, expeditious and eco-friendly chlorination of activated arenes by N-chloro-N-(phenylsulfonyl)benzene sulfonamide (NCBSI)
Misal, Balu,Palav, Amey,Ganwir, Prerna,Chaturbhuj, Ganesh
supporting information, (2021/01/04)
N-Chloro-N-(phenylsulfonyl)benzene sulfonamide (NCBSI) has been explored for the first time as a chlorinating reagent for direct chlorination of various activated arenes and heterocycles without any activator. A comparative in-silico study was performed to determine the electrophilic character for NCBSI and commercially available N-chloro reagents to reveal the reactivity on a theoretical viewpoint. The reagent was prepared by an improved method avoiding the use of hazardous t-butyl hypochlorite. This reagent was proved to be very reactive compared to other N-chloro reagents. The precursor of the reagent N-(phenylsulfonyl)benzene sulfonamide was recovered from aqueous spent, which can be recycled to synthesize NCBSI. The eco-friendly protocol was equally applicable for the synthesis of industrially important chloroxylenol as an antibacterial agent.
Fabrication of magnetically separable ruthenium nanoparticles decorated on channelled silica microspheres: Efficient catalysts for chemoselective hydrogenation of nitroarenes
Das, Manash R.,Das, Pankaj,Kalita, Gauravjyoti D.
, p. 13483 - 13496 (2021/10/12)
Fe3O4-SiO2microspheres were synthesized by a three-step synthetic procedure involving silica coating, surface capping, and surface modification. These magnetic mesoporous microspheres were employed as sorbents for the incorporation of ultrasmall Ru nanoparticles (2-5 nm) followed by thermal aggregation of the microspheres for achieving better heterogeneity and low leaching. The Ru decorated Fe3O4-SiO2microspheres (Ru@Fe3O4-CSM) were applied as chemoselective catalysts to convert more than 20 substituted nitroarenes to corresponding amines with good-to-excellent conversion (77-99%) and selectivity (70-100%) under mild conditions; the catalyst can be magnetically recovered within a frame of 90s (recovery time-lapse) and reused up to 5 times without significant decrease in activity or selectivity. Magnetic hysteresis studies were performed to elucidate the magnetic behavior of the ruthenium decorated materials.
Unlocking Amides through Selective C–N Bond Cleavage: Allyl Bromide-Mediated Divergent Synthesis of Nitrogen-Containing Functional Groups
Govindan, Karthick,Chen, Nian-Qi,Chuang, Yu-Wei,Lin, Wei-Yu
supporting information, p. 9419 - 9424 (2021/11/30)
We report a new set of reactions based on the unlocking of amides through simple treatment with allyl bromide, creating a common platform for accessing a diverse range of nitrogen-containing functional groups such as primary amides, sulfonamides, primary amines, N-acyl compounds (esters, thioesters, amides), and N-sulfonyl esters. The method has potential industrial applicability, as demonstrated through gram-scale syntheses in batch and in a continuous flow system.
Environment-friendly preparation method of 2-chloro-4-nitro-6-bromoaniline
-
Paragraph 0040; 0043; 0046; 0049; 0051; 0054; 0056; 0059, (2020/05/02)
A preparation method of 2-chloro-4-nitro-6-bromoaniline comprises the following steps: (a) carrying out mixed acid nitration on o-dichlorobenzene, and continuing to apply the generated waste acid to anext nitration reaction; (b) purifying the obtained nitration product in an alcohol solvent to obtain 3,4-dichloronitrobenzene, and continuously applying the recovered alcohol solvent to a next purification process; (c) carrying out ammonolysis on the 3,4-dichloronitrobenzene in a water phase by adopting a specific catalyst to prepare o-chloro-p-nitroaniline, and continuously applying the recycled liquid ammonia to a next ammonolysis reaction; and (d) brominating o-chloro-p-nitroaniline in a hydrogen bromide and oxidant system, and recycling brominated waste acid liquid and bromine for a nextbromination reaction. The product obtained by the method is good in yield, high in purity and high in quality; and two waste acids and bromine in the product are recycled, so that the amount of wastewater is reduced. Compared with traditional processes, the method has obvious quality and environmental protection advantages, and has high production safety.
Environment-friendly 2, 6-dichloro-4-nitroaniline preparation method
-
Paragraph 0037-0057, (2020/08/27)
The invention discloses an environment-friendly 2, 6-dichloro-4-nitroaniline preparation method, and belongs to the field of environmental protection. The environment-friendly 2, 6-dichloro-4-nitroaniline preparation method comprises the following steps: step 1, adding o-dichlorobenzene, namely a component shown as a formula (I), into a nitric acid and sulfuric acid solution for reaction to obtainm-nitro-1, 2-dichlorobenzene, namely a component shown as a formula (II); step 2, adding the m-nitro-1, 2-dichlorobenzene obtained in the step 1 into an ammonia water solution for reaction to obtain2-chloro-4-nitroaniline, namely a component shown as a formula (III); step 3, dropwise adding hydrochloric acid and a hydrogen peroxide solution into the 2-chloro-4-nitroaniline obtained in the step 2. According to the new preparation method, the generation of polychlorophenol during the 2, 6-dichloro-4-nitroaniline preparation process is effectively reduced, the environmental protection meets therequirements of OECO-Textile 100, and a dye obtained after the actual production of the preparation method directly meets the requirements of OECO-Textile 100.
Cyclic synthesis method of nitroaniline chloride
-
Paragraph 0028; 0029; 0036; 0037, (2020/10/05)
The invention discloses a cyclic synthesis method of nitroaniline chloride. The cyclic synthesis method comprises the following steps: (1) mixing nitroaniline and sulfuric acid, and preheating to a chlorination reaction temperature; (2) respectively inputting the solution obtained in the step (1) and chlorine into a reactor to carry out a chlorination reaction, cooling the material obtained in thereaction to obtain a supersaturated solution, and crystallizing to separate out a supersaturated product namely nitroaniline chloride; and (3) carrying out solid-liquid separation on the material cooled in the step (2), carrying out flash evaporation on the obtained saturated nitroaniline chloride/sulfuric acid solution, recycling hydrogen chloride, and circulating hydrogen chloride to the step (1) to replace sulfuric acid for dissolving nitroaniline, thereby realizing cyclic synthesis of nitroaniline chloride. Product super-saturation precipitation and saturated solution circulation are realized, the proportion of raw materials in a reaction system is reduced, the reaction is promoted to enter a uniform liquid phase system, meanwhile, mother liquor can be recycled, and the purposes of high efficiency, controllability and comprehensive utilization of resources are achieved.
UREA-SUBSTITUTED AROMATIC RING-LINKED DIOXANE-QUINAZOLINE AND -LINKED DIOXANE-QUINOLINE COMPOUNDS, PREPARATION METHOD THEREFOR AND USE THEREOF
-
Paragraph 0051-0052, (2020/01/22)
The present invention relates to a urea-substituted aromatic ring-linked dioxane-quinazoline compound of Formula (I) and a urea-substituted aromatic ring-linked dioxane-quinoline, or a pharmaceutically acceptable salt thereof or a hydrate thereof. Also provided are the preparation of the compound as shown in Formula (I) and the pharmaceutically acceptable salt thereof and the use thereof as a drug. The drug is used as an inhibitor of tyrosine kinases (e.g., VEGFR-2, C-RAF, B-RAF) for treating tyrosine kinase-related diseases.
