96-91-3Relevant academic research and scientific papers
A Common, Facile and Eco-Friendly Method for the Reduction of Nitroarenes, Selective Reduction of Poly-Nitroarenes and Deoxygenation of N-Oxide Containing Heteroarenes Using Elemental Sulfur
Cerecetto, Hugo,Romero, Angel H.
supporting information, (2020/03/23)
A transition metal-free, environment-friendly and practical protocol was developed either for the reduction of nitroarenes or for the deoxygenation of N-oxide containing heteroarenes. The reaction proceeded with the use of a non-toxic and cheap feedstock as elemental sulfur in aqueous methanol under relatively mild conditions. Green chemistry credentials were widely favorable compared to traditional and industrial protocols with good E-factors and a low production of waste. The strategy allowed the efficient reduction of a large variety of substituted-nitroarenes including various o-nitroanilines as well as selective reduction of various poly-nitroarenes in excellent yields with a broad substrate scope. The protocol was successfully extended to the deoxygenation of some N-oxide containing heteroarenes, like benzofuroxans, phenazine N,N'-dioxides, pyridine N-oxides, 2H-indazole N1-oxides, quinoxaline N1,N4-dioxides and benzo[d]imidazole N1,N3-dioxides. A gram-scale example for the synthesis of luminol, in green conditions, was reported. A solid mechanism of reaction was proposed from experimental evidences.
Fine tuning the performance of multiorbital radical conductors by substituent effects
Mailman, Aaron,Wong, Joanne W.L.,Winter, Stephen M.,Claridge, Robert C.M.,Robertson, Craig M.,Assoud, Abdeljalil,Yong, Wenjun,Steven, Eden,Dube, Paul A.,Tse, John S.,Desgreniers, Serge,Secco, Richard A.,Oakley, Richard T.
, p. 1625 - 1635 (2017/02/10)
A critical feature of the electronic structure of oxobenzene-bridged bisdithiazolyl radicals 2 is the presence of a low-lying LUMO which, in the solid state, improves charge transport by providing additional degrees of freedom for electron transfer. The magnitude of this multiorbital effect can be fine-tuned by variations in the π-electron releasing/accepting nature of the basal ligand. Here we demonstrate that incorporation of a nitro group significantly stabilizes the LUMO, and hence lowers Ueff, the effective Coulombic barrier to charge transfer. The effect is echoed, at the molecular level, in the observed trend in Ecell, the electrochemical cell potential for 2 with R = F, H and NO2. The crystal structures of the MeCN and EtCN solvates of 2 with R = NO2 have been determined. In the EtCN solvate the radicals are dimerized, but in the MeCN solvate the radicals form superimposed and evenly spaced πstacked arrays. This highly 1D material displays Pauli-like temperature independent paramagnetic behavior, with χTIP = 6 × 10-4 emu mol-1, but its charge transport behavior, with σRT near 0.04 S cm-1 and Eact = 0.05 eV, is more consistent with a Mott insulating ground state. High pressure crystallographic measurements confirm uniform compression of the π-stacked architecture with no phase change apparent up to 8 GPa. High pressure conductivity measurements indicate that the charge gap between the Mott insulator and metallic states can be closed near 6 GPa. These results are discussed in the light of DFT band structure calculations.
Exothermic thermal reaction of dopamine with 3,5-dinitrobenzoic acid
Ito, Yoshikatsu,Arimoto, Satoru
, p. 849 - 857 (2007/10/03)
Pyrolysis of the crystalline 1:1 molecular complex DA·dnba, which was prepared from cocrystallization of dopamine (DA) and 3,5-dinitrobenzoic acid (dnba), was studied. This cocrystal decomposed violently at the melting-point, leading to the formation of a black solid along with a tiny amount of 3-amino-5-nitrobenzoic acid (1). The pyrolysis reaction was followed by differential scanning calorimetry (DSC) and one large exothermic peak was observed at the decomposition temperature. In view of the DSC patterns for cocrystal DA·dnba and other compounds, it seems that both a catechol moiety and an amino group of DA in addition to a strong electron acceptor such as dnba are required for the appearance of the exothermic peak. On the basis of (a) elemental analysis of the black solid and (b) other pyrolysis experiments for cocrystals PA·dnba (PA: β-phenylethylamine), BA·dnba (BA: benzylamine), DMDA·dnba (DMDA: O,O′-dimethyldopamine) and DHBA·dnba (DHBA: 3,4-dihydroxybenzylamine), it is assumed that the black solid was formed mainly through elimination of more than one molecule of water from one molecule of DA·dnba. Copyright
Nitration of o-Aminophenol, o-Anisidine, and o-Benzenediazonium Oxide in Sulfuric Acid
Gorelik,Shteiman,Shner,Romanskii,Kuznetsova
, p. 348 - 352 (2007/10/03)
Entering into a reaction in the protonated form, o-aminophenol is nitrated in 80% sulfuric acid at the para and ortho positions to the hydroxy group to afford a mixture of 4-nitro- and 6-nitro-2-aminophenol and is nitrated and sulfonated in concentrated sulfuric acid, whereas o-anisidine is nitrated at the para positions in both cases, converting into 4-nitro-2-aminoanisole. After diazotization of o-aminophenol and subsequent nitration of o-benzenediazonium oxide, a mixture of the same derivatives as in diazotization of the nitration products of o-aminophenol is formed, but the 6-nitro isomer prevails.
Unsymmetrical 1:2-chromium complexes containing an azo compound and an azomethine compound
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, (2008/06/13)
Compounds of the formula: STR1 WHICH ARE EMINENTLY SUITABLE FOR DYEING NATURAL AND SYNTHETIC POLYAMIDES AND FOR COLORING SURFACE COATINGS. Dyeings on textile material are distinguished by very good lightfastness and very good fastness to wet treatments, for example fastness to water, perspiration, sea water and washing.
Process for the manufacture of symmetric 1:2 chromium complexes of azo dyes
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, (2008/06/13)
The present invention relates to a process for the manufacture of 1:2 chromium complexes of metallisable azo dyes, wherein the azo dyes are treated in aqueous solution at pH 7 to 9 with at least the stoichiometric amount of a chromium complex, and, in the course of the chroming, the reaction medium is acidified once or repeatedly to a pH of 6 or less and subsequently brought back again to pH 7 to 9.
