59-89-2Relevant academic research and scientific papers
Release of nitrosating species in the course of reduction of benzo-1,2,3,4-tetrazine 1,3-dioxides.
Ratnikov, Maxim O,Lipilin, Dmitry L,Churakov, Aleksandr M,Strelenko, Yuri A,Tartakovsky, Vladimir A
, p. 3227 - 3229 (2007/10/03)
[reaction: see text] The reduction of benzo-1,2,3,4-tetrazine 1,3-dioxides (BTDOs) 1 with Na(2)S(2)O(4) or SnCl(2) is suggested to proceed via intermediate N-nitrosobenzotriazoles 3 to afford benzotriazoles 2. The (15)N-labeling experiments exhibit that t
Pseudophase Approach to Reactivity in Microemulsions: Quantitative Explanation of the Kinetics of the Nitrosation of Amines by Alkyl Nitrides in AOT/Isooctane/Water Microemulsions
Garcia-Rio, L.,Leis, J. R.,Mejuto, J. C.
, p. 10981 - 10988 (2007/10/03)
The kinetics of the nitroso group transfer from 2-ethoxyethyl (EEN) and 2-bromoethyl (BEN) nitrit+e to the secondary amines piperazine (PIP), N-methylbenzylamine (NMBA), and morpholine (MOR) in bis(2-ethylhexyl) sulfosuccinate (AOT)/isooctane(iC8)/water microemulsions were determined.They are explained quantitatively in terms of a model in which the reagents are distributed among the aqueous, organic, and AOT film surfactant, with the aqueous pseudophase and the surfactant film as the losi of the reaction.
Reactions of Secondary Nitramines with Tributyltin Hydride and Tris(trimethylsilyl)silane
Imrie, Christopher
, p. 328 - 329 (2007/10/03)
The reactions of secondary nitramines (N-nitroamines) with tributyltin hydride or tris(trimethylsilyl)silane have been investigated under free radical conditions.Reactions of nitramines with tributyltin radicals gave mostly the denitration products (secondary amines) whilst reactions with tris(trimethylsilyl)silyl radicals afforded almost exclusively nitrosamines (N-nitrosoamines).
Reactivity of Nucleophilic Nitrogen Compounds towards the Nitroso Group
Garcia-Rio, Luis,Iglesias, Emilia,Leis, J. Ramon,Pena, M. Elena,Rios, Ana
, p. 29 - 37 (2007/10/02)
We discuss the reactivity of 43 nucleophilic nitrogen compounds towards the nitroso group of N-methyl-N-nitrosotoluene-p-sulfonamide (MNTS), and in some cases with alkyl nitrites.The series of nucleophiles considered is structurally very varied, includes members exhibiting the alpha effect, and covers 8 pKa units and a range of reactivities of almost five orders of magnitude.The values of solvent isotope effects and activation parameters have been measured and throw light on the structure of the transition states involved.Reactivities do not correlate well with thebasicity of the nucleophile, largely owing to the behaviour of primary amines, ammonia and nucleophiles with an alpha effect.Application of the curve crossing model suggests a relationship with vertical ionization potentials.The relationship with Ritchie's N+ scale is discussed, and interesting correlations with the reactivities of the same nucleophiles in various other chemical processes are noted.
Transfer of the Nitroso Group in Water/AOT/Isooctane Microemulsions: Intrinsic and Apparent Reactivity
Garcia-Rio, Luis,Leis, J. Ramon,Pena, M. Elena,Iglesias, Emilia
, p. 3437 - 3442 (2007/10/02)
The kinetics of the transfer of the nitroso group from N-methyl-N-nitroso-p-toluenesulfonamide to each of seven secondary amines (piperazine, N-methylbenzylamine, piperidine, dimethylamine, morpholine, pyrrolidine, and diisopropylamine) was studied using a wide variety of water/AOT/isooctane microemulsions as reaction media.The diverse kinetic behavior of the various amines can be explained quantitatively on the basis of a single model taking into account the distribution of the amine among the aqueous and isooctane phases and their mutual interface; the reaction itself always takes place at the interface.The relative reactivities of the amines are discussed in comparison with the order observed in water.
Formation of Nitrosamines in Alkaline Conditions: a Kinetic Study of the Nitrosation of Linear and Cyclic Secondary Amines by Nitroalkanes
Calle, Emilio,Casado, Julio,Cinos, Jose L.,Mateos, Francisco J. Garcia,Tostado, Manuel
, p. 987 - 991 (2007/10/02)
A study has been made of the nitrosation of sixteen secondary amines, six alkylamines (dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, diisobutylamine) and ten cyclic secondary amines (2-methylaziridine, azetidine, pyrrolidine, piperidine, 2-methylpiperidine, homopiperidine, heptamethyleneimine, piperazine, 1-methylpiperazine and morpholine) by nitropropane and nitrobutane in a strongly basic medium (-> = 0.1 mol dm-3).The nitrites were not formed in situ (i.e. in the actual bulk of the reaction medium) but rather were isolated,purified and used in pure form.The rate equation (i) was found v = k2obs (i).The fitting of the experimental results to the Taft correlation points to a nucleophilic attack on nitrite esters by the amines.Analysis of the log k2/pKa and log k2/Ei(v) correlations indicates orbital control of the reactions studied.These results, together with the fact that the reactivity of the different amines diminishes ostensibly when the values of the 13C-H nuclear spin coupling constant in the series of corresponding cycloalkanes increase, show that the overall hybridization of the nitrogen atom in the cycle changes from sp2 in the triangular nucleophile methylaziridine to sp3 in larger cycles.The results obtained at different temperatures and with water-tetrahydrofuran media, together with a study of isotope effects suggest that these reactions occur through a highly ordered transition state and that the role of solvation should not be overlooked.
Facile Formation of N-Nitrosamines from Bromonitromethane and Secondary Amines
Challis, Brian C.,Yousaf, Taher I.
, p. 1598 - 1599 (2007/10/02)
Bromonitromethane readily converts secondary amines to N-nitrosamines in aqueous and organic solvents at room temperature via reaction of an iminium ion intermediate with nitrite ion.
Nitrite Ion as a Nitrosating Reagent. Nitrosation of Morpholine and Diethylamine in the Presence of Formaldehyde
Casado, Julia,Mosquera, Manuel,Paz, L. Carlos,Prieto, M. Flor Rodriguez,Tato, Jose Vazquez
, p. 1963 - 1966 (2007/10/02)
The kinetics of the nitrosation of morpholine and diethylamine in the presence of formaldehyde has been studied at pH values between 6.5-8.2 and 6.9-8.7, respectively.The results are interpreted through a mechanism that implies the reaction between both the nitrite NO2(-) and iminium R2N(+)=CH2 ions.The latter ion results from the dehydration of the conjugated acid of the carbinolamine, R2NH(+)CH2OH, the initial product of the amine-formaldehyde reaction.The results allow the calculation of the equlibrium constants of the formation of carbinolamine, R2NCH2OH, and methanediamine, R2NCH2NR2 (only for the morpholine-formaldehyde system), and their conjugate acids.
Base-Induced Fragmentation of β-Hydroxy Nitrosamines
Loeppky, R. N.,McKinley, W. A.,Hazlitt, L. G.,Outram, J. R.
, p. 4833 - 4841 (2007/10/02)
β-Hydroxy nitrosamines have been found to undergo a base-induced fragmentation reaction.The reaction cleaves the Cα-Cβ bond of the substrate to produce an aldehyde or ketone and a smaller alkylnitrosamine.Rate contants for the fragmentation induced by potassium tert-butoxide in THF or tert-butyl alcohol have been measured for nine substrates at temperatures between 35 and 70 deg C.The rate constants are a function of base concentration and range between 0.15x10-6 and 308x10-6 s-1.Rate constants have been determined for (2-hydroxyethyl)methylnitrosamine,N-nitrosodiethanolamine, (2-hydroxy-2-methylpropyl)methylnitrosamine, (2-hydroxy-2-phenylethyl)methylnitrosamine, N-nitrosoephedrine, (2-hydroxy-2,2-diphenylethyl)methylnitrosamine, and (2-hydroxy-2-phenylpropyl)methylnitrosamine.The nitrosamino alcohol fragmentation rates are in the order tertiary > secondary > primary, and the rate appears to be a function of product stability and steric strain in the substrate.A mechanism which accounts for these observations is proposed.
1-Amino-2-phthalimido-diazene-1-oxides: Formation, Properties and Fragmentation Reactions into Imido- and Amino-nitrenes
Hoesch, Lienhard
, p. 890 - 904 (2007/10/02)
Oxidatively generated phthalimido-nitrene (1) reacts with the nitrosoamines 2a-d (see Scheme 1) to give the corresponding (Z)-1-amino-2-phthalimido-diazene-1-oxides 3a-d in good yields.With the O-nitroso compound 2e, no addition of the nitrene 1 took place.The constitution of the adducts 3 (R = NR2') is deduced from their spectroscopic properties (UV., IR., 1H-NMR. and MS.) as compared to those of (Z)-1-aryl- and (Z)-1-alkyl-2-phthalimido-diazene-1-oxides 3 (R = aryl and alkyl, resp.).The (Z)-configuration of 3 (R = NR2') follows from an X-ray analysis wich is reported separately.Compounds 3 (R = NR2') are cleaved photolytically as well as by acid to the corresponding nitrosoamines 2 (R = NR2') and the nitrene 1, which could be trapped by cyclohexene to give 40percent of 7-phthalimido-7-azabicycloheptane (8) and by dimethylsulfoxide to yield 96percent of S,S-dimethyl-N-phthalimido-sulfoximide (13).Nucleophilic attack leads to fragmentation of 3 (R = NR2') into derivatives of phthalic acid and degradation products of intermediate aminonitrenes 24 corresponding to the respective nitrosoamines 2 (R = NR2') with loss of oxygen.A general rationalization for the formation of 24 includes as a key step a N-to C-migration of the O-atom (see Scheme 6).The final fate of 24 is depending of the type of the nucleophile used.Thus, hydrazinolysis of 3b and of 3c generates besides N,N'-phthalohydrazine (15), morpholine (14) from 3b and 1,3-dihydroisoindole (16) together with 6'-methylidene-1,2,3,4-tetrahydronaphthalene-2-spiro-1'-cyclohexa-2',4'-diene (17) from 3c (see Scheme 5).Treatment of 3b and of 3c with sodium methylate leads in both reactions to monomethyl phthalate (33) and, with 3b, to1,2-dimorpholinodiazene (31) and, with 3c, to 17 (see Scheme 7).Finally, the reaction of 3b with diethylamine generates N,N-diethylphthalamic acid (36), morpholine (14), 1,1,4,4-tetraethyl-2-tetrazene (34) and 1,1-diethyl-4,4-(3-oxapentamethylene)-2-tetrazene (35) (see Scheme 8).
