Aromatic hydrocarbon—polar group interaction compounds

Aromatic hydrocarbon-polar group interaction in microemulsions, effect of aromatic compounds, 41,4 /... 

Isolated compounds include alkyl, aromatic, ahcyclic, or functional groups with significant hydrocarbon structure. All isolates have a potential for nonpolar interaction (except inorganic ions and compounds with polar groups, e.g., carbohydrates). Because of this fact, the nonpolar interactions are nonselective and allow the extraction of... 

As seen in Fig. 10, in aromatic hydrocarbons the Jt-electron-rich regions can interact with cations through so-called cation-7t interactions [40], In mixtures with ionic liquids, the aromatic molecules may be solvated in the nonpolar domains but they may have sufficient affinity for the cationic head-groups to be found among the polar domain as well. When looking at the structure of such mixtures, it is useful to study the local environments of the ions and of the aromatic compound. 

Compounds, such as those containing the aromatic nucleus and thus tt electrons, are polarizable. When such molecules are in close proximity to a molecule with a permanent dipole, the electric field from the dipole induces a counterdipole in the polarizable molecule. This induced dipole acts in the same manner as a permanent dipole and, thus, polar interactions occur between the molecules. Induced-dipole interactions are, as with polar interactions, always accompanied by dispersive interactions. Aromatic hydrocarbons can be retained and separated in GC purely by dispersive interactions when using a hydrocarbon stationary phase or they can be retained and separated by combined induced-polar and dispersive interactions using a poly(ethylene glycol) stationary phase. Molecules can possess different types of polarity, phenyl ethanol, for example, will possess both a permanent dipole as a result of the hydroxyl group and also be polarizable due to the... 

Essential oils contain a variety of compounds divided into two main groups hydrocarbons and oxygenated compounds. For garden mint, the essential oil is mainly carvone (oxygenated monoterpene) and limonene (monoterpene hydrocarbon). How does the microwave energy effect differ for these two different aroma compounds It would be reasonable to believe that the more polar the compound the more readily the microwave irradiation is absorbed, because of the better interaction between the electromagnetic wave and compound, so the oil obtained contains more of the more polar aromatic components. This would seem to correspond well to the observed behavior of carvone (polar compound) and limonene (non polar compound) (Table 22.5). 

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