Arenes aromaticity

K. H. Saunders andR. L. M. ARen, Aromatic Dla Compounds., Edward Arnold, London, UK, 1985. 

EPA Method 25A is the instrumental analyzer method for determination of total gaseous organic concentration using a flame ionization analyzer. The method apphes to the measurement of total gaseous organic concentration of vapors consisting primarily of alkanes, alkenes, and/or arenes (aromatic hydrocarbons). The concentration is expressed in terms of propane (or other appropriate organic calibration gas) or in terms or carrion. 

Alkenes, alkynes, and arenes (aromatic compounds) all contain carbon-carbon multiple bonds. Alkenes have a double bond, alkynes have a triple bond, and cneues have alternating double and single bonds in a six-membered ring of carbon atoms. Because of their structural similarities, these compounds also have chemical similarities. 

Arenes. Aromatic hydrocarbons, as a class, are called arenes. 

Fullerenes can be derivatized by various means. For example, reaction with fluorine gas proceeds stepwise to the formation of colorless CeoFeo, which, according to the 19F nuclear magnetic resonance (NMR) spectrum, contains just one type of F site and so evidently retains a high degree of symmetry.9 In view of the low adhesion typical of fluorocarbons, this spherical molecule is expected to have extraordinary lubricant properties. Curiously, bromination of Ceo is reversible on heating otherwise, the reactions of fullerenes resemble those of alkenes or arenes (aromatic hydrocarbons). 

Oxidation of Other Arenes. Aromatic compounds with longer alkyl side chains can be converted to ketones or carboxylic acids. All the previously discussed reagents except Cr02Cl2 usually afford the selective formation of ketones from alkyl-substituted arenes. Oxidation with Cr02Cl2 usually gives a mixture of products. These include compounds oxidized in the P position presumably formed via an alkene intermediate or as a result of the rearrangement of an intermediate epoxide.110,705... 

Hydrocarbons contain only hydrogen and carbon. The hydrocarbon functional groups include alkanes, alkenes, alkynes, and arenes (aromatic compounds). Simple hydrocarbons have few medicinal applications, but are the feedstock of the petrochemical industry to produce plastics, dyes, solvents, detergents, and adhesives (to name just a few). Therefore, hydrocarbons are essential to the medical field. Additionally, all hydrocarbons are flammable and, therefore, find application as fuels. For example, gasoline is a mixture of hydrocarbons. 

The geometry of achiral dimeric calix[4]arene endowed with urea functionalities offers further possibilities to obtain homodimeric chiral capsules. In fact, simply employing two different substituents A and B on the urea or on the ether part of the calix[4]arene aromatic rings and considering all the possible combinations depicted in Fig. 19, it was possible to obtain up... 

Given a Lewis structure, a condensed formula, or a line drawing for an organic compound, identify it as representing an alkane, alkene, alkyne, arene (aromatic), alcohol, carboxylic acid, ether, aldehyde, ketone, ester, amine, or amide. 

The whole argument is organized in four sections stoichiometric acylations, catalytic homogeneous acylations, catalytic heterogeneous acylations, and phenol acylations. It is structured according to the role played by the catalyst in the activation of reagents as well as in the different modes of regioselectivity encountered in the acylation of arenes, aromatic ethers, and phenols. 

Grimmer, G., K.W. Naujack, and G. Dettbarn Gas chromatographic determination of polycyclic aromatic hydrocarbons, aza-arenes, aromatic amines in the particle and vapor phase of mainstream and sidestream smoke of cigarettes Intemat. Exptl. Toxicol. Symp. on Passive Smoking, Essen ERG (1986) pp. 1-19 Toxicol. Lett. 35 (1987) 117-124. 

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