Aliphatic monoamines

Monoamine ligands in ruthenium(II) complexes have been reported to undergo oxidative dehydrogenation to imines benzylamine affords benzaldimine (and benzonitrile) [7] and cyclohexylamine yields cyclohexanone imine [8]. 

The catalytic dehydrogenation of primary aliphatic amines to nitriles by the CuCl/py system at room temperature has been reported [9,10]. 

According to an improved version of that procedure, primary amines (1) can be catalytically converted to nitriles (2) in the presence of the CuCl/py/O system with added 4 X molecular sieve, at 60 °C and 1 

In the proposed mechanism, supported by kinetic results, an oxocopper(II) dimer [PY Cu Cl O plays the role of the active oxidant 

The kinetics of diethylamine oxidation by molecular oxygen catalyzed by Ru(III) ion and Ru(III)-EDTA complex has been studied in aqueous solution at 35 [16]. The main reaction products are the corresponding imine, N-hydroxyethylamine and acetaldehyde. The proposed mechanism involves formation of a ruthenium amide complex which undergoes -hydride elimination. 

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For aliphatic monoamine [43], it is shown that secondary amines R2NH always possess a higher promoting effect for the polymerization of AAM and even the primary amine PA will enhance the polymerization with Rr = 1.47 and Ea = 36.4 kJ/mol, while the tertiary aliphatic amine TPA will not provide the polymerization due to some steric hindrance (Table 6). All of the data of cyclic amines listed in Table 7 are effective, i.e., NMMP with Rr = 1.81 and Ea = 29.9 kJ/mol showing the absence of steric hindrance. 

The treatment of aliphatic monoamines, benzil monooxime, benzil monohydrazone, and alkyl, monohaloalkyl arylketoximes bearing two or three a-hydrogens with tetrasulfur tetranitride to afford 1,2,5-thiadiazoles was presented in CHEC(1984) and CHEC-II(1996). 

MAO Inhibitors. MAO is an enzyme which oxidizes a variety of monoamines. Among the substrates of this enzyme are tyramine, tryptamine, 5-hydroxytryptamine, histamine, and short chain aliphatic monoamines ( ). Oxidation of histamine to imidazoleacetaldehyde can be carried out by DAO as well as MAO. is also responsible for the conversion of N -MH, the product of HMT, to N -MIAA. Many MAO inhibitors have been identified they are conventionally divided into hydrazides, hydrazines and amines (44). Some MAO inhibitors, e.g. the hydrazines, are non-selective they also inhibit DAO. 

Aliphatic Amines The molecular ion peak of an aliphatic monoamine is an odd number, but it is usually quite weak and, in long-chain or highly branched amines, undetectable. The base peak fre-... 

Like ammonia, the simple aliphatic monoamines are gases at room temperatnre, bnt as the length of the... 

Butylamine was not shown to be mutagenic in Salmonella in tests reviewed. Millimolar concentrations of various primary aliphatic monoamines have been shown to cause the release of lysosomal beta-glucuronidase in cultured mouse peritoneal macrophages. In selected culture systems exposed to butylamine, lysosomal enzymes were selectively released. 

The enzyme was crosslinked by glutaraldehyde to collagen fibril and fixed to an O2 probe. Maximal sensitivity was found with hexylamine and some other aliphatic monoamines. Tyramine and histamine were indicated with 30% sensitivity. 

CATALYTIC OXIDATION OF NITROGEN COMPOUNDS WITH O2 10.1.2. Aliphatic monoamines... 

Aliphatic monoamines can be oxidized to imines and nitriles with 0 and Cud I) or Ru(II) catalysts, presumably via inner-sphere electron... 

Several simple aliphatic monoamines, formed by decarboxylation of amino acids or by transamination of aldehydes, occur widely in plants (Fig. 28.1) (Geissman and Grout, 1969 Guggisberg and Hesse, 1983 Smith, 1977a,b). Many involve subsequent N-methylation. These compounds are called protoalkaloids in some references (Hegnauer, 1988) more than 1100 compounds of this type are known (Verpoorte et al., 1991). 

An amine oxidase has been purified from pea seedlings by Mann and associates (197,198). The purified enzyme catalyzed the oxidation not only of diamines but also of phenylalkylamines, aliphatic monoamines, and of L-lysine. The rates of oxidation for the latter three were less than for the diamines. The oxidation of all compounds was similarly affected by cyanide and semicarbazide. The conclusion reached was that a single enzyme is involved which is less specific than animal diamine oxidase. 

The specificity of animal diamine oxidase has been reinvestigated by Fonts et al. (119). Hog kidney cortex served as the source of partially purified diamine oxidase. According to these workers monoamine oxidase is easily separated from diamine oxidase since monoamine oxidase is exclusively present in particulate matter (however, see I40). Twenty-six monoamines (aliphatic monoamines, amino alcohols, phenylalkylmonoamines) were tested and thirteen were shown to be attacked by diamine oxidase, although much less readily than the diamines. Semicarbazide (111, 187) and aminoguanidine (188), which do not effect monoamine oxidase, blocked the oxidation and deamination of the monoamines. In contrast, the oxidation was not affected by iproniazid, a powerful inhibitor of monoamine oxidase but not of diamine oxidase (169-161). Simultaneous oxidation of mono-and diamines did not lead to additive oxidation rates. In view of these results it was concluded that mammalian diamine oxidase does attack monoamines at a reduced rate. Apparently the second basic group of the diamines is not required for the formation of the enzyme substrate complex... 

Many compounds have been studied as possible inhibitors of diamine oxidase because of the finding that the so-called antihistamine drugs inhibit diamine oxidase. Ammonia (190), aliphatic monoamines (191), ephed-rine (199), and choline (191) are weak inhibitors, whereas guanidines (193), imidazole (194), basic dyes such as pyocyanine (195), methylene blue (196), and toluylene blue (195), diamines such as thiamine (197), pyridoxamine (197), piperazine (197), and diamidines (198) (such as 4,4 -diamidinostilbene and its dimethyl derivative) are potent competitive... 

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