Properties and Sources of Amines

Caffeine is a bitter-tasting compound found in coffee, tea, cola beverages, and chocolate. Caffeine is a mild stimulant, usually imparting a feeling of alertness after consumption. It also increases heart rate, dilates airways, and stimulates the secretion of stomach acid. Caffeine is an alkaloid, a naturally occurring amine derived from a plant source. In Chapter 25 we learn about the properties and reactions of amines. 

Complexation of macrocyclic ligands to lanthanide cations has been studied extensively [207,208], One main reason for the current interest in those macro-cyclic complexes are their intrinsic paramagnetic and luminescent properties. There is also the steadily increasing number of tailor-made macrocyclic ligands [209], This section will focus on complexes which contain macrocycles as discrete counterions and in particular on the coordination chemistry of phthalocyanine (Pc) and porphyrin (Por) ligands. Schiff base ligands which display another source of amine functionalities are usually not deprotonated under the prevailing reaction conditions [210]. 

Halib, N., Amin, M. C. 1. M., and Ahmad, I. (2012). Physicochemical properties and characterization of Nata de Coco from local food industries as a source of cellulose. Sains Malays., 41(2), 205-211. 

Phosphoms pentafluoride behaves as a Lewis acid showing electron-accepting properties. It forms complexes, generally in a ratio of 1 1 with Lewis bases, with amines, ethers, nitriles, sulfoxides, and other bases. These complexes are frequently less stable than the similar BF complexes, probably owing to stearic factors. Because it is a strong acceptor, PF is an excellent catalyst especially in ionic polymeri2ations. Phosphoms pentafluoride is also used as a source of phosphoms for ion implantation (qv) in semiconductors (qv) (26). 

Despite the fact that many boron hydride compounds possess unique chemical and physical properties, very few of these compounds have yet undergone significant commercial exploitation. This is largely owing to the extremely high cost of most boron hydride materials, which has discouraged development of all but the most exotic appHcations. Nevertheless, considerable commercial potential is foreseen for boron hydride materials if and when economical and rehable sources become available. Only the simplest of boron hydride compounds, most notably sodium tetrahydroborate, NajBHJ, diborane(6), B2H, and some of the borane adducts, eg, amine boranes, are now produced in significant commercial quantities. 

The mechanism of amide formation is a source of insight into the properties of carboxylic acids and amines. Initially, we might expect an amine to act as a base and simply accept a proton from the carboxylic acid. Indeed, that does happen, and a quaternary ammonium salt is formed when the reagents are mixed in the absence of a solvent. For example,... 

Extensive developments in the preparation of the enantiomers of chiral nitroso and nitro compounds have not appeared since the earlier review1, and thus no additional discussion of the sources of nitroso and nitro compounds is made in this supplement. However, because of the continuing interest in carcinogenic properties of /V-nitrosamines and related compounds24, there has been a number of reports concerning the ECD and VCD of such compounds, and the ECD and VCD of nitrosamines are discussed as derivatives of chiral amines. 

Air, water, soil, and food are all unavoidable components of the human environment. Each of those elements influences the quality of human life, and each of them may be contaminated. Food is not only the elementary source of nutrients, but may also contain natural chemical substances with toxic properties, e.g., cyanogenic glycosides (many plants), solanine (green parts of potatoes, sprouted potatoes, and potatoes stored in light), industrial pollutants (heavy metals), biogenic amines (fish), or mycotoxins (moldy foodstuffs). 

Nitroaromatic compounds (NACs) are one of the widespread contaminants in the environments. Sources of NACs are numerous they originate from insecticides, herbicides, explosives, pharmaceuticals, feedstock, and chemicals for dyes (Agrawal and Tratnyek, 1996). Under anaerobic conditions, the dominant action is nitro reduction by zero-valent iron to the amine. Other pathways do exist, such as the formation of azo and azoxy compounds, which is followed by the reduction of azo compounds to form amines. Also, in addition to the possibility of azo and azoxy compounds, phenylhydrox-ylamine may be an additional intermediate (Agrawal and Tratnyek, 1996). Nitrobenzene reduction forms the amine aniline. Known for its corrosion inhibition properties, aniline cannot be further reduced by iron. Additionally, it interferes with the mass transport of the contaminant to the surface of the iron. The overall reaction is as follows ... 

Before leaving the matter of amines, we should examine some of the known simpler ones for their effects upon the circulation, especially as to cardiac action and duration of pressor response. The former is noteworthy, as its absence is a necessary prerequisite of the Hochdruckstoff. Presumably an extended vasospastic action should also be a prerequisite. Prolonged action can be produced in at least four ways (1) by some property inherent in the structure of the molecule of the pressor agent which prevents its rapid destruction in situ or in blood (2) by slow liberation of an effector substance from a larger, more complex molecule or system (3) by inhibition of the action of an enzyme system which inactivates some naturally occurring pressor agent and (4) by continuous production from parent sources. Clear-cut examples are not evident at present, although... 

Stable salts can be synthesized that have very low melting points for electrochemical and other applications. The neutralization method introduced in this chapter is an easy way to prepare pure salts and to use them in learning about the structure-property relationships of salts. It has been shown that excellent onium salts can be obtained from the results of neutralized amines. Besides serving as sources of qua-temized onium salts, neutralized amines have excellent properties. Some of these are unique and not retained by ordinary onium salts. More vigorous studies on neutralized amines can be expected to be published in the near future. 

Haywood, G. W., and Large, P. J., 1981, Microbial oxidation of amines dish ibution, purification and properties of two primary amine oxidases from die yeast Candida boidinii grown on amines as sole nitrogen source, Biochem. J. 199 187n201. 

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