31077-80-2

Upstream product

• 62-53-3 aniline 
• 586-96-9 Nitrosobenzene 
• 100-65-2 N-Phenylhydroxylamine 

Downstream Products

• 495-48-7 azoxybenzene 
• 586-96-9 Nitrosobenzene 

Relevant academic research and scientific papers

Mechanochemically induced cross-dimerizations of nitrosobenzenes. Kinetics and solid-state isotope effects

Mechanical treatment (milling) of crystals of aromatic nitroso dimers (azodioxides) induces their dissociation and cross-dimerizations. The mechanisms of these processes are discussed on the basis of kinetic studies and the solid-state 15 N kinetic isotope effect, which is measured for the first time. By comparison with analogous processes in cocrystals and in melts, it appears that the reactions follow similar mechanism in which the surface deformations play the crucial role. The system can also be used as a model for a more general conceptual study of solid-state reaction mechanisms. Copyright

Photothermal reactions of nitrosobenzene and halonitrosobenzenes in solid-state

Photothermal reactions of the dimers of nitrosobenzene, m-chloronitrosobenzene, and p-chloronitrosobenzene were studied in solid-state by IR spectroscopy at low temperatures and by X-ray powder diffraction. It was found for the first time that photothermal cycle (photolytic dissociation fol-lowed by thermal dimerization) could successively be performed also with Z-configured dimeric nitroso-benzene. Halonitrosobenzenes dimers with E-configuration afforded different photo behavior depending on the po-sition of halogen atom on the benzene ring: while m-halonitrosobenzenes do not dissociate under UV ir-radiation, p-chloronitrosobenzene, as well as previously studied p-bromonitrosobenzene photolyses very efficiently with recovering of the original crystal phase. Kinetics of thermal dimerization was measured in solid-state, and it was found that the reaction phase transformation occurs as a two-dimensional growth through the crystal.

Nitrosobenzene cross-dimerization: Structural selectivity in solution and in solid state

Possibility of nitrosobenzenes to form dimeric molecular structures (azodioxides) is used as a model for intermolecular selectivity investigations in solution as well as in solid state. Cross-dimerization of different combinations of p- and m-substituted nitrosobenzene pairs was studied by variable temperature 1H NMR, solid-state NMR (CP MAS), IR, and ab initio calculations. It is evident that p-nitronitrosobenzene behaves nonselectively because it forms dimers with all the studied nitrosobenzene partners. In contrast, p-methoxynitrosobenzene in most cases does not form dimers. The evidence that ability to form dimers is different in solution than in the solid state can be explained by influence of molecular arrangements in the crystal lattice.

Structural investigations of C-nitrosobenzenes. Part 2. NMR studies of monomer-dimer equilibria including restricted nitroso group rotation in monomers

Energy barriers associated with rotation of nitroso groups in monomeric nitrosobenzene and eleven monomeric substituted nitrosobenzenes in solution have been measured by total 1H NMR bandshape analysis. ΔG? (298.15 K) values for the rotations are in the range 31-41 kJ mol-1. The values for 4-substituted compounds correlate well with the Hammett σp+ parameter for the substituent. The experimental energy barrier for nitrosobenzene is compared with theoretical calculations. Monomerdimer equilibria of these compounds in solution have been investigated, with ΔH, ΔSominus; and ΔGominus; data calculated for the dissociation of both Z- and E- azodioxy dimers to monomers. Kinetic data, based on time-dependent and two-dimensional exchange spectroscopy (2D-EXSY) NMR measurements, have been obtained for the dissociation of 3-methylnitrosobenzene and 3,5-dimethylnitrosobenzene dimers. Energy profiles for the ground and transition states of both dimers and monomers (including exchange between both their rotameric forms) are discussed.

Oxidation of Aromatic Amines with Hydrogen Peroxide Catalyzed by Cetylpyridinium Heteropolyoxometalates

Various substituted anilines 1 were selectively converted into the corresponsing nitrosobenzenes 2 or nitrobenzenes 3 by oxidation with aqueous hydrogen peroxide catalyzed by heteropolyoxometalates.The oxidation of anilines 1 with 35percent H2O2 catalyzed by peroxotungstophosphate (PCWP) at room temperature in chloroform under two-phase conditions afforded nitrosobenzene 2 with high selectivity.When the same reactions were carried out at higher temperature (e.g., refluxing chloroform), nitrobenzenes 3 were obtained in good yields.The oxidation of aniline (1a) with dilute H2O2 catalyzed by PCWP (2 wtpercent) in an aqueous medium produced azoxybenzene (4a) with high selectivity.Phenylazoxyalkanes 7 were prepared by the first direct cooxidation of 1a in the presence of primary aliphatic amines 6.For example, the oxidation of a 1:2 mixture of 1a and hexylamine (6b) with 35percent H2O2 (6 equiv) in the presence of PCWP produced phenylazoxyhexane (7b) along with a small amount of 4a (8percent).The reaction path for the conversion of anilines to azoxy-, nitroso-, and nitrobenzenes is described.

Oxidation of Aliphatic and Aromatic Amines with Hydrogen Peroxide Catralyzed by Peroxoheteropoly Oxometalates

Peroxotungstophosphate (PCWP) was found to be an efficient catalyst for the oxidation of amines with 35percent H2O2 under the biphasic or homogeneous condition.Thus, primary and secondary amines were oxidized to oximes and nitrones, respectively, in good yields.Aromatic amines afforded to the corresponding nitroso compounds and/or nitrobenzenes.

Study of the Monomer-Dimer Equilibrium of Nitrosobenzene Using Multinuclear One- and Two-Dimensional NMR Techniques

The monomer-dimer equilibrium of nitrosobenzene in CDCl3 solution was studied in the temperature range -50 to 30 deg C using 13C, 15N and 17O NMR spectroscopy.Decreasing temperature favours the dimeric azodioxy species, and below ca 10 deg C both cis and trans dimers were detected in addition to the monomer.The relative abundance of the trans dimer is low (* (298.15 K) being 65.8 +/-0.1 and 70.0 +/-0.3 kJ mol-1, respectively.Key words 13C, 15N, 17O NMR 13C 2D-EXSY nitrosobensene activation energies