Transfer nitration amines

The efficient At-nitration of secondary amines has been achieved by transfer nitration with 4-chloro-5-methoxy-2-nitropyridazin-3-one, a reagent prepared from the nitration of the parent 4-chloro-5-methoxypyridazin-3-one with copper nitrate trihydrate in acetic anhydride. Reactions have been conducted in methylene chloride, ethyl acetate, acetonitrile and diethyl ether where yields of secondary nitramine are generally high. Homopiperazine is selectively nitrated to At-nitrohomopiperazine or At, At -dinitrohomopiperazine depending on the reaction stoichiometry. At-Nitration of primary amines or aromatic secondary amines is not achievable with this reagent. 

The synthesis of 2-nitropyridazin-3(2//)-ones has been discussed in Section 8.01.5.5.5. These compounds showed excellent nitro group transfer properties allowing the N-nitration of secondary amines under mild neutral conditions <2003JOC9113>. 

Interaction within encounter pairs. The above arguments have assumed that there is no interaction between the components in the encounter pairs A. B and B.X (Scheme 3) but this is probably unrealistic. Stabilization of the encounter pair A. B by charge-transfer interaction should favour the pre-association path by reducing the value of k 3 and possibly also increasing that of k4 [cf. equation (46)].22 Thus, in the nitration of neutral amine molecules (X) by nitronium ions (B) in concentrated sulphuric acid, interaction between the components in the encounter pair ArNHJ.NOJ should increase the acidity of the N—H hydrogens and facilitate the formation of the free amine. In the bromination of aromatic compounds (B) by HOBr(A), interaction between the components should increase the concentration of the encounter pair ArH. HOBr and facilitate the protonation of the hypobromous acid. 

This involves the use of tertiary amine extraction of the An ions from acidic 11 M LiCl solutions. Spectroscopic studies have indicated that, in the cases of Am and Nd at least, the octahedral trianionic hexachloro complexes are extracted from 11 M LiCl. Stability constant data for the chloride complexing of Am , and Cfin media of ionic strength 1,0 have been reported. Tertiary amines also extract Pu and a study of extraction from nitrate media by trilaurylamine (TLA) in xylene has been reported. " This showed that the mass transfer rate was controlled by the reactions between Pu from the bulk phase and interfacially adsorbed TLA-HNOs. The separation of individual transplutonium elements from the Tramex actinide product may be achieved using ion exchange or precipitation techniques." ... 

Also highly nitrated compounds can be detected and identified by means of donors, such as hydrocarbons. Their identification was suggested by the method of thin-layer chromatography [103]. A method of rapid detection, of explosives such as TNT, TNB, Picryl chloride, wi-DNB, Tetryl in the form of charge-transfer complexes with aromatic amines, such as aniline, dimethylaniline, toluidines, anisidines, naphthylamines, benzidine etc. was developed by Dwivedy et al. [104]. The authors used for identification thin-layer chromatography establishing Rf values for model complexes. 

Many redox reactions by colloidal nanoparticles have been reported. Three of the most-studied reactions are (1) the catalyzed electron transfer between ferricyanide and thiosulfate [8,19-21], (2) the catalytic reduction of fluorescent dyes by sodium borohydride [22, 23], and (3) the catalytic reduction of organic compounds (e.g., nitro-aryls [9] and alcohols [24]). These reactions have been studied extensively because they are easy to follow spectroscopically allowing for straightforward measurement of reaction kinetics. The third set of reactions has enormous industrial significance, where nitro compounds are reduced to their less toxic nitrate or amine counterparts [25, 26] and the electrooxidation of methanol is utilized for methanol fuel cells [27, 28]. 

The conversion of naphthalene to 2-naphthoic acids by irradiation with carbon dioxide and electron donors (e.g. amines or dimethoxybenzene) has been further investigated and the quantum yields of the reaction measured for different solvents and donors. Electron transfer also occurs in the photochemical phosphonation of naphthalene and phenanthrene achieved by irradiation with trialkyl-phosphites and electron acceptors such as 1,3-dicyanobenzene. The photonitration of phenol in aqueous solutions of nitrate ion has been reported and phenols have been prepared by irradiation of substituted benzenes with the aromatic N-oxide (132). ... 

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