Aromatic ring phenols

Chains that include aromatic rings (phenols, pyridines, etc.) are said to be polycyclic and are stiffer, harder and more stable than aliphatic chains. Polycarbonate is an example, being hard enough for use in eyeglass lenses. An extreme example is Kevlar fiber. 

Phenols are compounds having the hydroxyl (OH) group attached directly to an aromatic ring. Phenols commonly found in pesticide wastewaters include chlorophenols, nitrophenols, and... 

Nitrosation of phenolic substrates usually uses nitrous acid prepared in situ from a dilute mineral acid and an alkali metal nitrite. In general, for every phenolic group present in a substrate an equal number of nitroso groups can be introduced into the aromatic ring phenol, resorcinol and phloroglucinol react with nitrous acid to form 4-nitrosophenol, 2,4-dinitrosoresorcinol and 2,4,6-trinitrosophloroglucinol respectively. 

What are phenolic compounds They are compounds that have one or more hydroxyl groups attached directly to an aromatic ring. Phenol (1.1) is the structure upon which the entire group is based. The aromatic ring in this case is, of course, benzene. 

Anilines, flammable liquids, unsaturated organics, lactic acid, coal, ammonia, powdered metals, wood, alcohols, electron-rich aromatic rings (phenols, analines)... 

Electron-rich aromatic rings (phenols, anilines), unsaturated hydrocarbons, potassium permanganate, chlorates, perchlorates... 

This was the first theory proposed and fitted in well with the majority of results. There can be no doubt that the aromatic ring, phenol, and the nitrogen groups are all important, but there is some doubt as to whether the ethylene bridge is important, since there are several analgesics which lack it (e.g. fentanyl). 

A type of organic compound in which at least one hydroxyl group is bound directly to one of the carbon atoms of an aromatic ring. Phenols do not show the behavior typical of alcohols. In particular they are more acidic because of the electron-withdrawing effect of the aromatic ring. The preparation of phenol itself is by fusing the sodium salt of the sulfonic acid with sodium hydroxide ... 

Aryldiazonium ions react with strongly activated aromatic rings (phenols and aromatic amines) to give azo compounds. For example,... 

Phenols are aromatic counterparts of alcohols but are much more acidic (pkia 10) because their anions are resonance stabilized by delocalization of the negative charge into the aromatic ring. Phenols can he oxidized to quinones by reaction with Fremy s salt (potassium nitrosodisulfonate), and quinones can he reduced to hydroquinones by reaction with NaBH4. 

---