Contents Other Aromatic Systems with

Tetrahydronaphthalene [119-64-2] (Tetralin) is a water-white Hquid that is insoluble in water, slightly soluble in methyl alcohol, and completely soluble in other monohydric alcohols, ethyl ether, and most other organic solvents. It is a powerhil solvent for oils, resins, waxes, mbber, asphalt, and aromatic hydrocarbons, eg, naphthalene and anthracene. Its high flash point and low vapor pressure make it usehil in the manufacture of paints, lacquers, and varnishes for cleaning printing ink from rollers and type in the manufacture of shoe creams and floor waxes as a solvent in the textile industry and for the removal of naphthalene deposits in gas-distribution systems (25). The commercial product typically has a tetrahydronaphthalene content of >97 wt%, with some decahydronaphthalene and naphthalene as the principal impurities. 

In all examples, excellent agreement was observed for the extent of the DNFB reaction or for the p-nitrobenzoyl contents with the difference between NaOH and NajCOa neutralization and with the content of hydrolysis-resistant methoxy groups. Of course, other hydroxyl groups of similar acidities, e.g., enols, would react in the same way as phenols. However, the presence of phenols at the periphery of an aromatic system is much more likely. 

The content of this article is restricted to systems with at least two aromatic molecules there are other sets of intermolecular interactions involving cations, or hydrogen-bonding molecules, interacting with the rr-delocal-ized aromatic molecules. 

The aniline point of crude oil is the temperature at which equal parts of aniline and the oil are completely miscible. For oils of a given type, the aniline point increases slightly with molecular weight but increases markedly with paraffinic character and may therefore be used to obtain an approximate estimation of aromatics content. Aniline point determinations are only infrequently applied to heavy oils and residua since their very character, and the other evaluation methods outlined here, indicates them to be complex with high proportions of ring systems (aromatic constituents and naphthene constituents). 

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