Volatile aliphatic amines

A. T. James. Biochem. J. 52, lAl-l (1952). Chromatography gas-liquid, volatile aliphatic amines, pyridines. 

Methylamine in fresh beef muscle is present at 2mg/kg, while the other volatile aliphatic amines (dimethyl-, trimethyl-, ethyl-, diethyl-and isopropylamine) are detected only in trace amounts. 

Elndler has described a special apparatus for carrying out the reaction of ketones, sulfur, and volatile aliphatic amines. When an amine is used which boils at approximately the desired temperature of reaction, no special closed apparatus is required, the reaction mixture being heated in conventional glass equipment under reflux condenser. A large-scale preparation starting with 373 g. of 2-acetylnaphthalene in a single run has been carried out (for experimental procedure see p. 97). ... 

If ammonia or a volatile aliphatic amine is evolved (similar odours) an ammonium salt of an acid or a salt of an aliphatic amine may be present. The separation of a base as a solid, oily layer or emulsion (careful observation required), probably denotes a salt of an aromatic amine or of a substituted hydrazine—cf. test 10. 

Therefore, CL and die depolymerized product from which CL is regenerated contain various impurities which are present in widely fluctuating amounts depending on the reclamation processes involved. In particular, the presence of cyclohexanone, cyclohexanone oxime, octahydrophenazine, aniline, and other easily oxidized compounds affects die permanganate number. Also volatile substances such as aniline, cyclohexylamine, cyclohexanol, cyclohexanone, nitrocy-clohexanone, and aliphatic amines may also be present in the CL.22... 

Of the primary monoamines, some, such as. aniline, o-toluidine, xylidine, are colourless liquids. Others, such as p-toluidine, pseudo-cumidine and the naphthylamines, are solids. They can be distilled without decomposition and are volatile with steam. In water they are rather sparingly soluble—a 3 per cent solution of aniline can be made. The di- and polyamines are usually solids, not volatile in steam and much more soluble in water than the monoamines. The amines are basic in character, but, as a result of the negative nature of the phenyl-group, the aromatic amines are considerably weaker bases than are the aliphatic amines. Consequently aqueous solutions of the (stoicheio-metrically) neutral aniline salts are acid to litmus because of the hydrolysis which they undergo. For the same reason a small amount of the free base can be extracted with ether from an aqueous solution of an aniline salt. (Test with a solution of hydrogen chloride in ether or, after evaporation of the ether, by the reaction with bleaching powder.)... 

The power and beauty of jet techniques is the ability to produce a beam of molecules that are vibrationally and rotationally cold but are still vapors. These advantages of supersonic expansions, however, rely on the possibility of producing sufficient partial vapor pressure of the molecules of interest, typically a few millibars. By regulating the temperature of the beam, it is possible to vary the vapor pressure of the sample to the required values. As an example, hquid molecules, such as aromatic alcohols, have to be heated at about 80 °C to obtain the right vapor concentration in the beam, while other largely volatile molecules, such as aliphatic amines, must be kept in a cold bath around 0 °C to avoid saturation. 

The aliphatic amines, including triethylene tetramine (TETA) and diethylene triamine (DETA), are highly alkaline (pH 13-14), caustic, and volatile and may cause severe... 

Twelve volatile acyclic amines and amides (114-120,125-129) (Table VIII) from ponerine ants in the genus Mesoponera have been identified by gas chromatography-mass spectrometry and mass spectral comparison with authentic synthetic samples 41). The major aliphatic amine, A-isoamylnonylamine (114), shows a molecular ion at m/z 213, a-cleavage fragments at miz 156 (M — C4H9)... 

TMA is a volatile aliphatic tertiary amine with a pungent odour resembling rotting fish (Fig. 7.4.1). TMA has a 100-fold greater olfactory potency than its N-oxide. The reported threshold odour for TMA is 0.9 ppm. Exposure to concentrations above 20 ppm gives moderate irritation of the respiratory system and the eyes. Dermal contact with a concentrated aqueous solution may cause severe burns [4]. Oral ingestion of 15 mg TMA hydrochloride/kg body weight induces nausea and ichthyo-hydrosis [9]. 

TMA, its N-oxide and related aliphatic amines like methylamine and dimethylamine in urine may be quantified using head-space gas chromatography [28] or direct injection of the head-space gas into the gas sample injection port of a mass spectrometer [27]. These methods take advantage of the volatility of the amines and evaluate the amine-rich head-space gas generated above the sample by direct injection. The... 

Mosier, A.R., Andre, C.E., and Viets, F.G., Jr., Identification of aliphatic amines volatilized from cattle feedyard, Environ. Sci. Technol., 7, 642, 1973. 

Glycidyl Adducts of Aliphatic Amines. An aliphatic amine such as diethylenetriamine can be partially reacted with an epoxy, such as a DGEBA resin, to produce a low-volatility adduct. In a typical reaction, the epoxy is added slowly to a large excess of DETA. The reaction is maintained at 75°C by cooling. The reaction products are continuously agitated effectively to provide for good contact and uniform concentration effects. At the end of the reaction, excess DETA is vacuum-distilled away from the adduct. 

The aliphatic amines are, in general, volatile liquids soluble in water. They are strong bases which turn litmus blue, and react with mineral acids to form neutral salts. The reaction to litmus — apart from the physical form — shows immediately whether the base or a salt is at hand. For the isolation and identification of aliphatic amines, the salts formed with picric acid and similar acids are of value. These salts are usually nicely crystalline and have characteristic melting points. 

BRUSH-OFF 45 LOW VOLATILE BRUSH KILLER (93-76-5) Sealed metal containers may burst in heat above 316°F/158°C. Incompatible with sulfuric acid, bases, ammonia, aliphatic amines, alkanolamines, isocyanates, alkylene oxides, epichlorohydrin. 

For GC analysis, HS is a preconcentration technique particularly suitable for the sampling of volatile organic compounds in air, water, and solids. Few reports have been published on the use of static headspace in the analysis of free amines in aqueous samples because of the high polarity and solubility in water of these compounds." In one experiment," static headspace preconcentration was developed for the gas chromatographic analysis of aliphatic amines in aqueous samples. A liquid-gas ratio of 1, an incubation temperature of 80°C (15 min), a pH of 13.7, and a mixture of salts (NaCl and K2SO4) at saturation concentration gave a maximal headspace amine concentration (Table 11.4). 

Organic residual components are the most worrying because of their toxicity. Some of these compounds are formed as by-products. Volatile organic compounds are determined by headspace GC, GC-MS. Intermediate products, such as sultones and sulfones, from sulfonation of olefin and alkyl-benzene, respectively, can be detected by LC. Unreacted products, like ethylene oxide from the synthesis of ethoxylated nonionic and anionic surfactants, are studied by GC benzyl chloride from the quaternization of tertiary amines and aliphatic amines from amidation reaction are determined by LC (Figure 5). 

Aliphatic amine Low cost, low viscosity, easy to mix, room temperature-curing, fast reacting High volatility, toxicity, short pot life, cured network can work up to 80 °C but not above... 

Volatile aliphatic secondary amines such as diethylamine (bp 55 °C) and dimethy-lamine (bp 7°C) have been used to ring-open azabenzonorbornadienes (Scheme 10.12). To simplify the practical procedure these amines were added as their corresponding hydrogen iodide salts [17b]. 

Several other types of curing agent based upon the aliphatic amine approach are also commonly used in epoxide formulations. Examples are the glycidyl adducts of the aliphatic amines, in which the aliphatic amine is partially reacted with an epoxide to give an adduct with low volatility. Similar types of adduct can also be made by reacting the amines with ethylene and propylene oxides. By forming such adducts, reaction rates can be increased, but the physical properties may deteriorate somewhat, and, in the case of the ethylene and propylene oxide adducts, the compounds are hygroscopic. 

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