156617-88-8Relevant articles and documents
Clay supported ammonium nitrate "clayan": A new reagent for selective nitration of arenes
Meshram,Ganesh,Madhavi,Eshwaraiah,Yadav,Gunasekar
, p. 2497 - 2503 (2003)
The nitration of activated, deactivated and highly functionalized arenes is described using clay-supported ammonium nitrate in the presence of perchloric acid.
Hydrophobic WO3/SiO2 catalyst for the nitration of aromatics in liquid phase
Kulal,Kasabe,Jadhav,Dongare,Umbarkar
, p. 105 - 113 (2019)
WO3/SiO2 solid acid catalyst synthesized using sol gel method has shown promising activity (up to 65% conversion) for aromatic nitration in liquid phase using commercial nitric acid (70%) as nitrating agent without using any sulfuric acid. The water formed during the reaction as well as water from dilute nitric acid (70%) was removed azeotropically, however due to the hydrophilic nature of the catalyst, some water gets strongly adsorbed on catalyst surface forming a barrier layer between catalyst and organics. This prevents effective adsorption of substrate on catalyst surface for its subsequent reaction. To improve the activity further, the hydrophilic/hydrophobic nature of the catalyst was altered by post modification by grafting with commercial short chain organosilane (Dynasylan 9896). The modified 20% WO3/SiO2 catalyst when used for o-xylene nitration in liquid phase, showed significant increase in the conversion from 65% to 80% under identical reaction conditions. Catalyst characterization revealed decrease in the surface area of 20% WO3/SiO2 from 356 m2/g to 302 m2/g after grafting with Dynasylan 9896. The fine dispersion of WO3 particles (2–5 nm) on silica support was not affected due to modification. NMR and FTIR study revealed the decrease in surface hydroxyl groups imparting hydrophobicity to the catalyst. Interestingly the total acidic sites of the catalyst remained almost unaltered (0.54 mmol NH3/g) even after modification. Even though, the acidity and other characteristics of the catalyst did not change appreciably, there was a considerable increase in the o-xylene conversion which can be ascribed to the hydrophobic nature of the catalyst.
Regioselective nitration of m-xylene catalyzed by zeolite catalyst
Dong, Xiongzi,Peng, Xinhua
, p. 1122 - 1128 (2015)
Nitration with nitric acid and acetic anhydride via acetyl nitrate as nitrating species is efficient with the substrate m-xylene as solvent. Zeolite Hβ with an SiO2/Al2O3 ratio of 500 was found to be the most active of the catalysts tried both in yield and regioselectivity in the nitration of m-xylene. The molecular volume of the reactants was calculated with the Gaussian 09 program at the B3LYP/6-311+G(2d, p) level and compared with the size of the zeolite Hβ channels. A range of other substrates were subjected to the nitrating system under the same conditions as those optimized for m-xylene and excellent selectivity was obtained.
Regioselective preparation of 4-nitro-o-xylene using nitrogen dioxide/molecular oxygen over zeolite catalysts. remarkable enhancement of para-selectivity
Liu, Hongtao,Ji, Cheng,Dong, Xiongzi,Peng, Xinhua,Shi, Chunjie
, p. 817 - 819 (2014)
In the presence of molecular oxygen and zeolite H-β with Si/Al 2 = 500, o-xylene reacted regioselectively with liquid nitrogen dioxide at 35 °C to yield mononitro-o-xylenes as the main product, where the 4-nitro-o-xylene isomer predominated up to 89% and the 4-nitro-/3-nitro-o- xylene isomer ratio improved to 7.8. The process is eco-friendly, less expensive, and the zeolite could be easily regenerated by a simple workup to afford results similar to those obtained with the fresh catalyst.
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Kobe,Pritchett
, p. 1398,1400, 1401 (1952)
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Photoinduced Iron-Catalyzed ipso-Nitration of Aryl Halides via Single-Electron Transfer
Wu, Cunluo,Bian, Qilong,Ding, Tao,Tang, Mingming,Zhang, Wenkai,Xu, Yuanqing,Liu, Baoying,Xu, Hao,Li, Hai-Bei,Fu, Hua
, p. 9561 - 9568 (2021/08/06)
A photoinduced iron-catalyzed ipso-nitration of aryl halides with KNO2 has been developed, in which aryl iodides, bromides, and some of aryl chlorides are feasible. The mechanism investigations show that the in situ formed iron complex by FeSO4, KNO2, and 1,10-phenanthroline acts as the light-harvesting photocatalyst with a longer lifetime of the excited state, and the reaction undergoes a photoinduced single-electron transfer (SET) process. This work represents an example for the photoinduced iron-catalyzed Ullmann-type couplings.
Cyhalofop-containing pesticide composition and application thereof
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Paragraph 0016; 0035; 0040-0041; 0046; 0051-0052; 0057; ...., (2021/11/26)
The invention discloses a pesticide composition containing cyhalofop-butyl and application thereof, belongs to the technical field of pesticide preparation and comprises 10 - 20 parts of cyhalofop-butyl. Tetramethyl chloride 3-5 parts, synergistic microcapsule 8-13 parts, wetting agent 1.5 - 4.5 parts, dispersing agent 1-3 parts, defoaming agent 0.5 - 1.5 parts and water 40 - 50 parts. When the water in the soil is less, the weed is absorbed by the chitosan so as to accelerate the absorption of A the synergic microcapsule and the cyhalofop-butyl ester, so that the pesticide composition is greatly reduced per mu.
Method and device for preparing methylnitro-benzene by channelization
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Paragraph 0047; 0048; 0049, (2019/02/04)
The invention discloses a method and a device for preparing methylnitro-benzene by channelization. The device comprises a storage tank, a nitrogen dioxide cylinder, an ozone generator, a flow pump, agas flowmeter, a reaction pipeline filled with a catalyst, a mixing pipeline, two T-shaped mixed joints, a cooling system, a heating system, a back pressure valve and a receiving tank. The method specifically comprises the following steps: opening the cooling system and the heating system; opening the ozone generator; arranging the flow pump and the gas flowmeter; and mixing raw materials liquid methyl benzene and nitrogen dioxide through the first T-shaped mixing joint and feeding the mixture into the mixing pipeline, then mixing the mixture with ozone in the second T-shaped mixing joint, feeding the mixture into the reaction pipeline filled with the catalyst for a nitrifying reaction, and post-treating a reaction liquid to obtain methylnitro-benzene. The method is controlled precisely and automatically, and is simple to operate, mild in reaction condition, simple in post treatment, quick to transfer mass and heat, high in safety and good in economical benefit.
