19519-71-2Relevant articles and documents
NMR Study of the Monomer-Dimer Equilibria of Dimethylnitrosobenzenes in Solution. Identification of Mixed Azodioxy Dimeric Species
Orrell, Keith G.,Stephenson, David,Rault, Thierry
, p. 368 - 376 (1989)
The monomer-dimer equilibria of 2,6- and 3,5-dimethylnitrosobenzenes in CDCl3 solution were investigated by 1H and/or 13C NMR spectroscopy.The mixed systems nitrosobenzene + 2,6-dimethylnitrosobenzene and 2,6-dimethylnitrosobenzene + 3,5-dimethylnitrosobenzene were also studied, and mixed azodioxy dimers were identified.In all systems exchange occurs exclusively between dimer and monomer species, rates and activation energies being calculated from time-dependent 1H 1D spectra and/or 1H 2D-EXSY spectra measured at different temperatures. KEY WORDS 1H NMR 13C NMR 2,6-Dimethylnitrosobenzene 3,5-Dimethylnitrosobenzene Monomer-dimer equilibria Mixed azodioxy dimers
Selective N-oxidation of aromatic amines to nitroso derivatives using a molybdenum acetylide oxo-peroxo complex as catalyst
Biradar, Ankush V.,Kotbagi, Trupti V.,Dongare, Mohan K.,Umbarkar, Shubhangi B.
, p. 3616 - 3619 (2008/09/19)
The molybdenum acetylide oxo-peroxo complex obtained in situ by the treatment of the corresponding molybdenum acetylide carbonyl complex, CpMo(CO)3(C{triple bond, long}CPh); Cp = η5-C5H5 with H2O2, has been used as an efficient catalyst for selective N-oxidation of primary amines to nitroso derivatives. Excellent amine conversion (up to 100%) and very high selectivity for nitroso compounds (99%) have been obtained using 30% hydrogen peroxide as an oxidant. The oxo peroxo Mo(VI) complex has also been found to be very active for the oxidation of various substituted primary aromatic amines with electron donating as well as electron withdrawing substituents on the aromatic ring.
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 (2007/10/02)
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.
