Amino compounds, oxidation

These are water-soluble crystalline compounds sold as concentrated aqueous solutions. The methylol groups are highly reactive (118—122) and capable of being cured on the fabric by reaction with ammonia or amino compounds to form durable cross-linked finishes, probably having phosphine oxide stmctures after post-oxidizing. This finishing process, as developed by Albright Wilson, is known as the Proban process. 

Water. Based on the overall balanced equation for this reaction, a minimum of one mole of water per mole of nitro compound is required for the reduction to take place. In practice, however, 4 to 5 moles of water per mole of nitro compound are used to ensure that enough water is present to convert all of the iron to the intermediate ferrous and ferric hydroxides. In some cases, much larger amounts of water are used to dissolve the amino compound and help separate it from the iron oxide sludge after the reaction is complete. 

One of the best methods of synthesis of isothiazoles is by direct oxidation of y- iminothiols (169) or their tautomers. The reaction is capable of many ramifications and is represented by the general equation shown in Scheme 27. The substituents represent a wide range of groups. Thus, iminothioamides (169 R = NH2) are oxidized to give 3-alkyl-5-aminoisothiazoles (170 = NH2), amidines (169 R = NH2) produce 3-amino compounds,... 

Transformations of nitro compounds, nitrones, nitrates, hydroxylamines, and amino-A-oxides into heterocycles 98SL939. 

The action of nitrous acid on the benzodiazepine A -oxide 38 gives the nitrosoamino derivative 39,234 which reacts with alcohols, ethanethiol and various amino compounds, such as hydrazines and guanidine, by replacement of the methyl(nitroso)amino group.235 Reaction with aziridine affords the aziridinyl compound 40f or the 2-(aziridin-l-yl)ethylainino derivative 40g, depending on the conditions. 

D. Miscellaneous.—A further study of the reactions of diphenyl-phosphine oxide with tetracyclone has confirmed that the reaction yields the oxide (30) under mild, basic conditions, and that the reaction is thermally reversible. The displacement of halogen from phosphorus by amino-compounds has been used in the synthesis of a number of aminofluoro-phosphine oxides (31), and of A-methyl-AA-bis(dichlorophosphinyl)-amine (32). ... 

Interaction of lipid oxidation products and amino compounds. Amino acids and primary amines may be involved in other reactions which could lead to the formation of compounds having the potential to undergo N-nitrosation. Malonaldehyde, produced as a result of oxidation of lipids, particularly polyunsaturated fatty acids, has been shown to react with amino acids to produce... 

Following this pnblication, the anthors tested a series of Pd-NHC complexes (33-36) for the oxidative carbonylation of amino compounds (Scheme 9.8) [44,45]. These complexes catalysed the oxidative carbonylation of amino compounds selectively to the nreas with good conversion and very high TOFs. Unlike the Cu-NHC catalyst 38-X, the palladium complexes catalysed the oxidative carbonylation of a variety of aromatic amines. For example, 35 converted d-Me-C H -NH, d-Cl-C H -NH, 2,4-Me3-C H3-NH3, 2,6-Me3-C H3-NH3, and 4-Ac-C H3-NH3 to the corresponding nreas with very high TOFs (>6000) in 1 h at 150°C, in 99%, 87%, 85%, 72%, and 60% isolated yields, respectively (Pco,o2 = 3.2/0.8 MPa). 

Microbial growth, enzymatic reactions, non-enzymatic browning (reaction between carbonyl and amino compounds), and lipid oxidation are the major deterioration mechanisms that limit the stability of low moisture (o intermediate moisture foods (o.6o < <0.85) and biological materials. 

One of numerous examples of LOX-catalyzed cooxidation reactions is the oxidation and demethylation of amino derivatives of aromatic compounds. Oxidation of such compounds as 4-aminobiphenyl, a component of tobacco smoke, phenothiazine tranquillizers, and others is supposed to be the origin of their damaging effects including reproductive toxicity. Thus, LOX-catalyzed cooxidation of phenothiazine derivatives with hydrogen peroxide resulted in the formation of cation radicals [40]. Soybean LOX and human term placenta LOX catalyzed the free radical-mediated cooxidation of 4-aminobiphenyl to toxic intermediates [41]. It has been suggested that demethylation of aminopyrine by soybean LOX is mediated by the cation radicals and neutral radicals [42]. Similarly, soybean and human term placenta LOXs catalyzed N-demethylation of phenothiazines [43] and derivatives of A,A-dimethylaniline [44] and the formation of glutathione conjugate from ethacrynic acid and p-aminophenol [45,46],... 

The most unambiguous description of amino compounds of the type (XVII) was in terms of the parent phosphine oxide. 

Fig. 5. Biological oxidation reactions of primary, secondary and tertiary amino compounds...

Consequently, by choosing proper conditions, especially the ratios of the carbonyl compound to the amino compound, very good yields of the desired amines can be obtained [322, 953]. In catalytic hydrogenations alkylation of amines was also achieved by alcohols under the conditions when they may be dehydrogenated to the carbonyl compounds [803]. The reaction of aldehydes and ketones with ammonia and amines in the presence of hydrogen is carried out on catalysts platinum oxide [957], nickel [803, 958] or Raney nickel [956, 959,960]. Yields range from low (23-35%) to very high (93%). An alternative route is the use of complex borohydrides sodium borohydride [954], lithium cyanoborohydride [955] and sodium cyanoborohydride [103] in aqueous-alcoholic solutions of pH 5-8. 

An alternative nucleophilic attack at the 7-position is given in Scheme 21. The oxidation of the 7-benzylsulfanyl substituent of 33 with w-chloroperbenzoic acid (MCPBA) resulted in the corresponding sulfone 34. The 7-sulfones were found to be unstable, and used immediately to facilitate a nucleophilic substitution by various primary amines or ammonia. The transformation of sulfide 33 into 7-amino compound 35 was accomplished in 80% overall yield <2004JHC575>. 

T. Shono, Kagaku (Kyoto) 42, 642 643 (1987) Synthesis of Physiologically Active Amino Compounds using Anodic Oxidation as the Key Step". 

Protection of amino compounds by the 2,4-bis(methylthio)phenoxycarbonyl residue [266] converts them into acid stable entities. Removal of the protecting group can be achieved through oxidation at sulfur such that the resulting bissulfone provides conjoint pathways for ready fragmentation. 

In laboratory model systems using reduced DOM constituents (Dunnivant et al., 1992), Fe(II) adsorbed to iron (hydr)oxides (Klausen et al., 1995), or zero-valent iron metal (Agrawal and Tratnyek, 1996) as reductants, the nitroso- and particularly the hydroxylamino compounds have been observed as reaction intermediates, but were ultimately also converted to the corresponding amino-compounds. 

From a practical point of view, reduction of NACs is of great interest for two reasons. First, the amino compounds formed may exhibit a considerable (eco)toxi-city, and therefore may be of even greater concern as compared to the parent compounds. Additionally, the reduced products may react further with natural matrices, in particular with natural organic matter, thus leading to bound residues (see sections on oxidations below). One prominent example involves the reduction products of the explosive, 2,4,6-trinitrotoluene (TNT see Fig. 14.6), particularly the two isomeric diaminonitrotoluenes (2,4-DA-6-NT and 2,6-DA-4-NT) and the completely reduced triaminotoluene (TAT). These have been found to bind irreversibly to organic matter constituents present in soils (Achtnich et al., 2000) and sediments (Elovitz and Weber, 1999). This process offers interesting perspectives for the treatment of NAC contaminated sites. In fact, a dual step anaerobic/aerobic soil slurry treatment process has been developed for remediation of TNT contaminated soils (Lenke et al., 2000). 

Nitro compounds are easily reduced, catalytically or chemically, to amino compounds. Incomplete reduction can lead to a hydroxylamino derivative or to binuclear azo, azoxy and hydrazo compouds, e.g. (760) — (759), (761). A nitro group can be reduced in the presence of an iV-oxide group, e.g. (755) - (752). 

Amino- (459) and 3-amino-quinazolin-2-ones (460) (75JCS(Pl)3l), as well as 1-amino- and 2-amino-indazoles (92AHC(53)85) can be oxidized to 1,2,3-benzotriazines. C-Amino compounds can also give triazines oxidation of 3-aminoindazole (461) with hydrogen peroxide forms 1,2,3-benzo-triazin-4-one (462) <1899LA(305)289). 

Aminofiavones are also available from chalcones derived from 5-acetamino-2-hydroxyacetophenone (57JOC304). Oxidation by selenium dioxide leads to 6-acetaminoflavones which may be deacetylated to the 6-amino compound, whilst alkaline hydrogen peroxide affords the corresponding flavonols (461) in a typical Algar-Flynn-Oyamada reaction (64CB610). 

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