F:Flammable;
88-89-1Relevant academic research and scientific papers
Kinetics and product distribution of 1-adamantyl picrate heterolysis in acetonitrile in the presence of triphenylverdazyls
Serebryakov,Moiseeva
, (2012)
The reaction of triphenylverdazyls with strong acids in acetonitrile in the presence of salts with chloride anion is reversible. The observed rate of the heterolysis of 1-adamantyl picrate in the presence of triphenylverdazyls does not depend on the subst
General-Base Catalysis in the Reaction of Water with Activated Aromatic Substrates. The Hydrolysis of 3-Methyl-1-picrylimidazolium Ion
Rossi, Rita H. de,Veglia, Alicia
, p. 1879 - 1883 (1983)
The rate of hydrolysis of 3-methyl-1-picrylimidazolium ion was investigated between pH 1.7 and 9.3 in the presence of several buffer bases at various concentrations.The reaction is strongly catalyzed by oxygen bases.The catalytic constants including water and OH- are spread over a range of ten powers of ten and show a good Broensted correlation with β=0.62.The kinetic solvent isotopic effect for the water-, acetate-, and OH--catalyzed reactions are 2, 0.86, and 0.84, respectively.The mechanism of catalysis is discussed, and it is concluded that it represents concerted addition of water to the aromatic ring.
Medium effect on the reaction of N-butyl-2,4,6-trinitroaniline with NaOH
Salum, Maria Laura,De Rossi, Rita H.,Bujan, Elba I.
, p. 2164 - 2174 (2007)
The kinetics of the reaction of N-butyl-2,4,6-trinitroaniline (3) with NaOH have been studied in 10 and 60% 1,4-dioxane/H2O at 25 °C. In both cases, several processes were observed. In 10% 1,4-dioxane/H2O the only product formed was 2,4,6-trinitrophenol (4), whereas in 60% 1,4-dioxane/ H2O a mixture of 4 and 5,7-dinitro-2-propyl-1H-benzimid- azole 3-oxide (5) was observed in ratios that depend on the HO- concentration. A mechanism involving the formation of a complexes through the addition of one or two HO- anions to unsubstituted ring positions is proposed for 2,4,6-trinitrophenol formation. The presence of these complexes was confirmed by NMR studies in 60% [D8]1,4-dioxane/D2O. The mechanism suggested for the formation of the N-oxide includes the cyclization of an N-alkylidene-2-nitrosoaniline-type intermediate as the rate-determining step. The decrease in solvent polarity produces a decrease in the observed rate constant for the formation of 4 of about one order of magnitude making the cyclization reaction a competitive pathway. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
Supramolecular structure of 2,4,6-trinitrophenol
Sun, Yin-Xia,Ren, Zong-Li,Meng, Wei-Sheng
, p. 6186 - 6188 (2013)
The compound 2,4,6-trinitrophenol with the molecular formula C6H3N3O7, crystallizes with two crystallographically independent but chemically identical molecules in the asymmetric unit. The dihedral angle formed by the two benzene rings is about 67.49. The
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.
Visible-Light-Induced Radical Polynitration of Arylboronic Acids: Synthesis of Polynitrophenols
Zhang, Qi,Raveendra Babu, Kaki,Huang, Zhouliang,Song, Jinna,Bi, Xihe
, p. 2891 - 2896 (2018/06/20)
We report a visible light-assisted one-pot method for the synthesis of polynitrophenols through radical tandem hydroxylation and nitration of arylboronic acids by utilizing copper(II) nitrate tri-nitydrate as the nitro source. This method features mild conditions, a simple procedure, and good functional group tolerance. Compared to conventional methods, this work provides a straightforward approach for the polynitration of aromatic compounds.
Effect of medium acidity on the efficiency of oxidation of 2,4,6-trinitrotoluene to 2,4,6-trinitrobenzoic acid
Мikhalchenko,Leibzon,Leonova, M. Yu.,Gultyai
, p. 2216 - 2219 (2017/05/12)
An effect of boric acid additives on oxidation of 2,4,6-trinitrotoluene (TNT) to 2,4,6-trinitrobenzoic acid (TNBA) with chromic anhydride in concentrated (96—100%) H2SO4 has been studied. In the presence of tetrahydrosulfatoboric acid HB(HSO4)4 formed in situ (up to 5 mol.%) or added as a preliminary prepared solution (up to 1 mol. %), TNT is selectively oxidized to TNBA in the yields up to 95—99%. The mechanism including formation of TNT dication as a key step of its oxidation at the methyl group has been suggested.
Tuning the intramolecular charge transfer (ICT) process in push-pull systems: Effect of nitro groups
Panja, Sumit Kumar,Dwivedi, Nidhi,Saha, Satyen
, p. 105786 - 105794 (2016/11/18)
The intramolecular charge transfer (ICT) process in donor-acceptor systems has tremendous importance in various physical and biological systems. Three nitrophenolate salts were synthesized and studied here. The ICT and π → π? transition processes were identified in these derivatives using UV-Vis spectroscopy and theoretical calculations. It was observed that by simple substitution with nitro groups, one can generate and control the ICT process by regulating the charge distribution over the molecule. While for a monosubstitute nitro derivative, only one ICT band was observed, additional ICT processes can be generated at will by introducing a second nitro group. The intensity of this second ICT channel can be regulated with introduction of a third nitro group. Further, the association constants and solvation processes for these potassium nitrophenolate derivatives were found to be drastically dependent on the number of ICT channels present in the molecule. Theoretical studies (MEP analysis) support the experimental observations presented here. The results show that by simply introducing additional acceptor groups to the system, one can tune the ICT band efficiently in a conjugate system.
O-Phenylisourea Synthesis and Deprotonation: Carbodiimide Elimination Precludes the Reported Chapman Rearrangement
Tate, Joseph A.,Hodges, George,Lloyd-Jones, Guy C.
, p. 2821 - 2827 (2016/07/07)
The kinetics of the addition of phenol to diisopropylcarbodiimide, and reaction of the resulting N,N′-diisopropyl-O-phenylisourea with hydroxide, are reported. The isourea is generated by a slow overall termolecular equilibrium process, inhibited by isourea–phenol salt generation. In contrast to an earlier report, reaction of the isourea with hydroxide does not induce a synthetically useful 1,3-O–N (Chapman) rearrangement. Instead, deprotonation results in solvolysis by carbodiimide elimination.
Spectroscopic and thermal investigations on the charge transfer interaction between risperidone as a schizophrenia drug with some traditional π-acceptors: Part 2
El-Habeeb, Abeer A.,Al-Saif, Foziah A.,Refat, Moamen S.
, p. 464 - 477 (2013/04/23)
The focus of present investigation was to assess the utility of non-expensive techniques in the evaluation of risperidone (Ris) in solid and solution states with different traditional π-acceptors and subsequent incorporation of the analytical determination into pharmaceutical formulation for a faster release of risperidone. Charge-transfer complexes (CTC) of risperidone with picric acid (PA), 2,3-dichloro-5,6-dicyano-p-benzoquinon (DDQ), tetracyanoquinodimethane (TCNQ), tetracyano ethylene (TCNE), tetrabromo-p-quinon (BL) and tetrachloro-p-quinon (CL) have been studied spectrophotometrically in absolute methanol at room temperature. The stoichiometries of the complexes were found to be 1:1 ratio by the photometric molar ratio between risperidone and the π-acceptors. The equilibrium constants, molar extinction coefficient (εCT) and spectroscopic-physical parameters (standard free energy (ΔGo), oscillator strength (f), transition dipole moment (μ), resonance energy (RN) and ionization potential (ID)) of the complexes were determined upon the modified Benesi-Hildebrand equation. Risperidone in pure form was applied in this study. The results indicate that the formation constants for the complexes depend on the nature of electron acceptors and donor, and also the spectral studies of the complexes were determined by (infrared, Raman, and 1H NMR) spectra and X-ray powder diffraction (XRD). The most stable mono-protonated form of Ris is characterized by the formation of +NH (pyrimidine ring) intramolecular hydrogen bonded. In the high-wavenumber spectral region ～3400 cm-1, the bands of the +NH stretching vibrations and of the pyrimidine nitrogen atom could be potentially useful to discriminate the investigated forms of Ris. The infrared spectra of both Ris complexes are confirming the participation of +NH pyrimidine ring in the donor-acceptor interaction.
