1196-12-9Relevant academic research and scientific papers
Enthalpies of combustion of 2,2',4,4',6,6'-hexamethylazobenzene-N,N-dioxide, 2,2',6,6'-tetramethylazobenzene-N,N-dioxide, 2,4,6-trimethylnitrobenzene, and 2,6-dimethylnitrobenzene: the dissociation enthalpies of the N=N and N-O bonds
Acree, W. E.,Tucker, Sheryl A.,Pilcher, G.,Chowdhary, Afza,Silva, Maria D. M. C. Ribeiro da,Monte, M. J. S.
, p. 1253 - 1262 (1993)
The standard (po=0.1 MPa) molar enthalpies of combustion at the temperature T=298.15 K were measured by static-bomb calorimetry for crystalline 2,2',4,4',6,6'-hexamethylazobenzene-N,N-dioxide (HMABOO), 2,2',6,6'-tetramethylazobenzene-N,N-dioxide (TMABOO), 2,4,6-trimethylnitrobenzene (NITME), and liquid 2,6-dimethylnitrobenzene (NITXY).The enthalpies of sublimation at the temperature 298.15 K of HMABOO and TMABOO were assessed from vapour-pressure measurements; the enthalpy of sublimation of NITME and the enthalpy of vaporization of NITXY were measured by microcalorimetry. .The standard molar enthalpies of decomposition of the crystalline N,N-dioxides to the corresponding gaseous monomeric nitroso-compounds at T=298.15 K were measured by microcalorimetry: for HMABOO, (18.1+/-2.5) kJ*mol-1, and for TMABOO, (179.2+/-2.2) kJ*mol-1.For HMABOO and TMABOO, D(N=N)/(kJ*mol-1) was derived as (74.1+/-12.2) and (72.2+/-12.2), and /(kJ*mol-1) as (285.7+/-6.8) and (287.8+/-6.6), respectively.D(N-O)/(kJ*mol-1) in NITME and in NITXY was derived as (383.4+/-2.9) and (380.4+/-2.3), respectively.
Addition reactions of a phosphorus triamide to nitrosoarenes and acylpyridines
Mattos, Jared T.,Radosevich, Alexander T.,te Grotenhuis, Colet
, p. 940 - 946 (2020)
Tricoordinate phosphorus compounds react with a wide variety of double bonds through addition reactions. The dipolar and cyclic products formed are important intermediates in organophosphorus chemistry. We investigated the reactivity between phosphorus triamide 1 and nitrosoarenes and 2-acylpyridines. For sterically congested substrates, the formation of σ5,λ5-phosphorus products is observed. DFT calculations indicate this product is formed through a concerted [4 + 1] mechanism. For less sterically congested substrates, products are observed arising from cleavage of the N = O or C = O bond with formation of a terminal P = O bond and aryl nitrene or carbene migration into a P–N bond of the phosphorus triamide core. DFT calculations are consistent with an initial [2 + 1] addition to phosphorus followed by formal carbene/nitrene migration in these cases.
Tungsten- and molybdenum-based coordination polymer-catalyzed N-oxidation of primary aromatic amines with aqueous hydrogen peroxide
Bordoloi, Ankur,Halligudi
, p. 2085 - 2088 (2007)
Recyclable tungsten- and molybdenum-based coordination polymers efficiently catalyzed the oxidation of primary aromatic amines to the corresponding nitroso derivatives with 30% aqueous hydrogen peroxide in high yields at room temperature.
Synthesis of Di(hetero)arylamines from Nitrosoarenes and Boronic Acids: A General, Mild, and Transition-Metal-Free Coupling
Roscales, Silvia,Csák?, Aurelio G.
supporting information, p. 1667 - 1671 (2018/03/23)
The synthesis of di(hetero)arylamines by a transition-metal-free cross-coupling between nitrosoarenes and boronic acids is reported. The procedure is experimentally simple, fast, mild, and scalable and has a wide functional group tolerance, including carbonyls, nitro, halogens, free OH and NH groups. It also permits the synthesis of sterically hindered compounds.
Titania-Supported Gold Nanoparticles Catalyze the Selective Oxidation of Amines into Nitroso Compounds in the Presence of Hydrogen Peroxide
Fountoulaki, Stella,Gkizis, Petros L.,Symeonidis, Theodoros S.,Kaminioti, Eleni,Karina, Athanasia,Tamiolakis, Ioannis,Armatas, Gerasimos S.,Lykakis, Ioannis N.
supporting information, p. 1500 - 1508 (2016/05/19)
In this article, the catalytic activity of titania-supported gold nanoparticles (Au/TiO2) was studied for the selective oxidation of amines into nitroso compounds using hydrogen peroxide (H2O2). Gold nanoparticles deposited on Degussa P25 polymorphs of titania (TiO2) have been found to promote the selective formation of a variety of nitroso arenes in high yields and selectivities, even in a large-scale synthesis. In contrast, alkyl amines are oxidized to the corresponding oximes under the examined conditions. Kinetic studies indicated that aryl amines substituted with electron-donating groups are oxidized faster than the corresponding amines bearing an electron-withdrawing functionality. A Hammett-type kinetic analysis of a range of para-X-substituted aryl amines implicates an electron transfer (ET) mechanism (ρ=-1.15) for oxidation reactions with concomitant formation of the corresponding N-aryl hydroxylamine as possible intermediate. We also show that the oxidation protocol of aryl amines in the presence of 1,3-cyclohexadiene leads in excellent yields to the corresponding hetero Diels-Alder adducts between the diene and the in situ formed nitrosoarenes.
Nitrosation of aryl and heteroaryltrifluoroborates with nitrosonium tetrafluoroborate
Molander, Gary A.,Cavalcanti, Livia N.
experimental part, p. 4402 - 4413 (2012/06/18)
Organotrifluoroborates have emerged as an alternative to toxic and air- and moisture-sensitive organometallic species for the synthesis of functionalized aryl and heteroaryl compounds. It has been shown that the trifluoroborate moiety can be easily converted into a variety of different substituents in a late synthetic stage. In this paper, we disclose a mild, selective, and convenient method for the ipso-nitrosation of organotrifluoroborates using nitrosonium tetrafluoroborate (NOBF4). Aryl- and heteroaryltrifluoroborates were converted into the corresponding nitroso products in good to excellent yields. This method proved to be tolerant of a broad range of functional groups.
Direct Nitrosation of Aromatic Hydrocarbons and Ethers with the Electrophilic Nitrosonium Cation
Bosch, Eric,Kochi, Jay K.
, p. 5573 - 5586 (2007/10/02)
Various polymethylbenzenes and anisoles are selectively nitrosated with the electrophilic nitrosonium salt NO(1+)BF4(1-) in good conversions and yields under mild conditions in which the conventional procedure (based on nitrile neutralization with strong acid) is ineffective.The reactivity patterns in acetonitrile deduced from the various time/conversions in Tables 2 and 3 indicate that aromatic nitrosation is distinctly different from those previously established for electrophilic aromatic nitration.The contrasting behavior of NO(1+) in aromatic nitrosation is ascribed to a rate-limiting deprotonation of the reversibly formed Wheland intermediate, which in the case of aromatic nitration with NO2(1+) occurs with no deuterium kinetic isotope effect.Aromatic nitroso derivatives (unlike the nitro counterpart) are excellent electron donors that are subject to a reversible one-electron oxidation at positive potentials significantly less than that of the parent polymethylbenzene or anisole.As a result, the series of nitrosobenzenes are also much better Broensted bases than the corresponding nitro derivatives, and this marked distinction, therefore, accounts for the large differentiation in the deprotonation rates of their respective conjugate acids (i.e.Wheland intermediates).
Monomer-Dimer Solution Equilibria of 2,4,6-Trialkylnitrosobenzenes and 2,4,6-Trialkylnitrosobenzene/Nitrosobenzene Mixtures. A Study Using One- and Twodimensional NMR Techniques
Orrell, Keith G.,Stephenson, David,Verlaque, James H.
, p. 1297 - 1303 (2007/10/02)
2,4,6-Trimethylnitrosobenzene in CDCl3 exists as a mixture of monomer and Z- and E-azodioxy dimers.The dissociation kinetics of both dimers were measured by one-dimensional time-dependent NMR spectroscopy on non-equilibrium solutions, and by two-dimensional exchange spectroscopy (2D-EXSY) on equilibrium solutions. 2,4,6-Tri-t-butylnitrosobenzene is entirely monomeric in CDCl3 but forms mixed azodioxy dimers in the presence of nitrosobenzene.The dissociation kinetics of the mixed E-dimer were followed by NMR techniques.The activation energy parameters for these dissociation equilibria were compared with previous data on related nitrosobenzene and dimethylnitrosobenzene systems.
PRESSURE EFFECT ON DIMERIZATION EQUILIBRIA OF A SERIES OF SUBSTITUTED NITROSOBENZENES IN SOLUTION.
Yoshimura,Nakahara
, p. 46 - 50 (2007/10/02)
The effect of pressure was studied on the dimerization reactions of six di- and tri-substituted nitrosobenzenes in carbon tetrachloride at 25 degree C. The obtained configurational volume changes for the prototype one bond formation reactions are in the range of minus 17 to minus 21 cm**3 mol** minus **1 at 6. 13 MPa. The volume changes were interpreted in terms of the perturbation theory of liquid; they were dominated by the volume change in the reference system composed of hard spheres. Small differences between the observed and theoretical reference volume changes were ascribed to the perturbation due to electrostatic interactions between the solute and solvent; the perturbation volume changes were estimated by the Kirkwood theory of dipolar solvation.
ACTIVATION VOLUME FOR DIMERIZATION REACTION OF 2,4, 6-TRIMETHYLNITROSOBENZENE IN SOLUTION.
Yoshimura,Nakahara
, p. 50 - 55 (2007/10/02)
The effect of pressure on the rate and equilibrium constants for the dimerization reaction of 2,4,6-trimethylnitrosobenzene in acetonitrile was studied up to 196 MPa at 25 degree C in order to examine whether the dynamical effect on the reaction process in solution can be neglected as assumed in the transition state theory. All the rate constants relevant to the dimerization were determined by the pressure relaxation method. The configurational reaction volume for the dimerization and the activation volume for the dissociation were minus 17. 4 plus or minus 0. 7 and plus 5. 1 0. 3 cm**3 mol** minus **1 at 98 MPa, respectively. The experimental results were in reasonable agreement with the theoretical ones that were calculated for the model system composed of hard spheres according to the liquid theory and the transition state theory.
