88-72-2Relevant articles and documents
Aromatic nitration with nitric acid/trifluoromethanesulfonic anhydride
Olah,Reddy,Prakash
, p. 1087 - 1089 (1992)
Nitric acid/trifluoromethanesulfonic (triflic) anhydride was shown to be a highly effective electrophilic nitrating agent. A series of aromatics were nitrated under mild conditions in high yields. Similar results were also obtained when using nitric acid/
Nitrobenzyl Derivatives as Bioreductive Alkylating Agents: Evidence for the Reductive Formation of a Reactive Intermediate
Kirkpatrick, D. L.,Johnson, K. E.,Sartorelli, A. C.
, p. 2048 - 2052 (1986)
o- and p-nitrobenzyl chlorides and carbamates were chemically and electrochemically reduced in the presence and absence of the nucleophile morpholine; activation of these compounds by reduction was required to produce an intermediate capable of alkylation.The reduction products formed by the catalytic hydrogenation of each compound were examined by gas chromatography-mass spectrometry.In addition, the products generated by controlled-potential electrolysis were examined by ESR and NMR spectrometry.After a one-electron reduction, o- and p-nitrobenzyl chlorides were activated to the nitrobenzyl radicals, which subsequently dimerized to the dinitrobibenzyl derivatives or reacted with morpholine when present in the reaction medium to form the (nitrobenzyl)morpholine adducts.The nitrobenzyl carbamates were not activated after a one-electron reduction; however, the morpholine and the ether adducts of these agents were observed after catalytic hydrogenation.It was assumed that an intermediate or intermediates formed after the one-electron reduction product, or the full reduction product of the carbamates, were capable of alkylating various nucleophiles.Chemical reduction of the potential bioreductive alkylating agent (o-nitrobenzyl)-6-thioguanine produced (o-aminobenzyl)-6-thioguanine, indicating a lack of formation of a reactive electrophile by reduction. (o-, (m-, and (p-nitrobenzyl)-6-thioguanine analogues were also examined for cytotoxic activity toward EMT6 tumor cells under aerobic and hypoxic conditions.In agreement with the inability of (o-nitrobenzyl)-6-thioguanine to form a reactive species after chemical reduction, no decrease in the survival of neoplastic cells exposed to 10-4 M drug occurred under either aerobic or hypoxic conditions.
Application of H-ZSM-5 Zeolite for Regioselective Mononitration of Toluene
Kwok, Thomas J.,Jayasuriya, Keerthi,Damavarapu, Reddy,Brodman, Bruce W.
, p. 4939 - 4942 (1994)
The nitration of toluene with n-propyl nitrate has been carried out in the presence of H-ZSM-5 as the catalyst.Several H-ZSM-5 catalysts with different Si/Al ratios were investigated to determine the influence of varying Si/Al ratios on the catalytic activity.It was found that high Si/Al ratios enhanced the regioselectivity for the p-nitrotoluene over the ortho isomer under comparable conditions.The best o:m:p product distribution (5:0:95) was achieved using H-ZSM-5 with a Si/Al ratio of 1000.The isolable yield is 54percent.In contrast to conventional nitration methods, the product distribution reported in this study is remarkable.
Some Aspects of Nitration of Aromatics by Lower Oxidation States of Nitrogen
Milligan, Barton
, p. 1495 - 1500 (1983)
Nitration of benzene and toluene in trifluoroacetic acid (TFA) solution with sodium nitrite (N(III)) and nitrogen dioxide (N(IV)) occurs relatively slowly to produce mononitroarenes and oxidized byproducts.The yield of nitroarene improves as the ratio of
Aromatic Substitution. 50. Mercury(II)-Promoted Azeotropic Nitration of Aromatics over Nafion-H Solid Superacidic Catalyst
Olah, George A.,Krishnamurthy, V. V.,Narang, Subhash C.
, p. 596 - 598 (1982)
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Regioselective catalyzed nitration of toluene by zeolites
Dong, Xiongzi,Peng, Xinhua
, p. 2341 - 2342 (2015)
The nitration of toluene with nitric acid and nitrogen dioxide as nitration agent was studied. The effect of zeolite catalysts was also discussed. By using zeolite as catalysis, the yield of nitro-toluene was improved with nitric acid as nitration agent. The conversion of toluene and yield of nitro-toluene were both greatly enhanced with nitrogen dioxide as nitration agent.
Selective Mild Oxidation of Anilines into Nitroarenes by Catalytic Activation of Mesoporous Frameworks Linked with Gold-Loaded Mn3O4 Nanoparticles
Armatas, Gerasimos S.,Daikopoulou, Vassiliki,Koutsouroubi, Eirini D.,Lykakis, Ioannis N.,Skliri, Euaggelia
, (2021/11/01)
This work reports the synthesis and catalytic application of mesoporous Au-loaded Mn3O4 nanoparticle assemblies (MNAs) with different Au contents, i. e., 0.2, 0.5 and 1 wt %, towards the selective oxidation of anilines into the corresponding nitroarenes. Among common oxidants, as well as several supported gold nanoparticle platforms, Au/Mn3O4 MNAs containing 0.5 wt % Au with an average particle size of 3–4 nm show the best catalytic performance in the presence of tert-butyl hydroperoxide (TBHP) as a mild oxidant. In all cases, the corresponding nitroarenes were isolated in high to excellent yields (85–97 %) and selectivity (>98 %) from acetonitrile or greener solvents, such as ethyl acetate, after simple flash chromatography purification. The 0.5 % Au/Mn3O4 catalyst can be isolated and reused four times without a significant loss of its activity and can be applied successfully to a lab-scale reaction of p-toluidine (1 mmol) leading to the p-nitrotulene in 83 % yield. The presence of AuNPs on the Mn3O4 surface enhances the catalytic activity for the formation of the desired nitroarene. A reasonable mechanism was proposed including the plausible formation of two intermediates, the corresponding N-aryl hydroxylamine and the nitrosoarene.
Nitration of aromatics with dinitrogen pentoxide in a liquefied 1,1,1,2-tetrafluoroethane medium
Fauziev, Ruslan V.,Kharchenko, Alexandr K.,Kuchurov, Ilya V.,Zharkov, Mikhail N.,Zlotin, Sergei G.
, p. 25841 - 25847 (2021/08/09)
Regardless of the sustainable development path, today, there are highly demanded chemical productions still operating that bear environmental and technological risks inherited from the previous century. The fabrication of nitro compounds, and nitroarenes in particular, is traditionally associated with acidic wastes formed in nitration reactions exploiting mixed acids. However, nitroarenes are indispensable for industrial and military applications. We faced the challenge and developed a greener, safer, and yet effective method for the production of nitroaromatics. The proposed approach comprises the application of an eco-friendly nitrating agent, namely dinitrogen pentoxide (DNP), in the medium of liquefied 1,1,1,2-tetrafluoroethane (TFE) - one of the most non-hazardous Freons. Importantly, the used TFE is not emitted into the atmosphere but is effortlessly recondensed and returned into the process. DNP is obtainedviathe oxidation of dinitrogen tetroxide with ozone. The elaborated method is characterized by high yields of the targeted nitro arenes, mild reaction conditions, and minimal amount of easy-to-utilize wastes.
NITRATION
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Page/Page column 36; 41; 46; 64; 37; 47; 42; 65, (2020/05/28)
The present invention relates to a process for preparing a nitrated compound, comprising the step of reacting a compound (A) comprising at least one substituted or unsubstituted aromatic or heteroaromatic ring, wherein said heteroaromatic ring comprises at least one heteroatom selected from the group consisting of oxygen, sulfur, phosphor, selenium and nitrogen, with a compound of formula (I) wherein Y is selected from the group consisting of hydrogen and nitro.