Phenyl alcohol; Phenyl hydrate; Fenol; Fenolo; Carbolic acid; Phenylic acid; Hydroxybenzene; Monohydroxybenzene; Phenyl hydroxide;
Phenol is the simplest aromatic alcohol which characterized by a hydroxyl (-OH) group attached to a benzene ring. The term phenol is not only for phenol itself but also for a class of aromatic compounds possessing a hydroxyl group attached to a benzene ring or a complex ring system. Phenol in water solution is sometimes called carbolic acid. Phenols differs from aliphatic alcohols which hydroxyl group is bonded to a saturated carbon atom. Due to the tendency of pi-orbital overlap between carbon and oxygen, phenol can lose easily the H+ ion from the hydroxyl group, resulting in higher acidity than aliphatic alcohols (but weaker acidity than carboxylic acids). The intermediate state losing hydrogen ion (H+) from the hydroxyl group in a phenol is called phenolate anion C6H5O-. It reacts with strong bases to form salts called phenolates.
Pure phenol is a white crystalline solid that melts at 41 C, boils at 182 C. It is moderately soluble in water and is soluble in ethanol and ether. Phenols form stronger hydrogen bonds than aliphatic alcohols and. Phenols are more soluble in water than alcohols and have higher boiling points. Many phenols have a sharp, spicy odour, but phenol smells bland and sweetish. It is highly toxic and caustic. Some phenols interfere with the endocrine system and disrupt the function of hormones. They have antiseptic property and are used in formulating disinfectants, deodorizers, and pesticides.
Phenol is synthesized by either the hydrolysis of chlorobenzene ( Raschig process) or the oxidation of cumene in air to form cumene hydroperoxide, which is then cleaved into phenol and acetone, a valuable by-product ( Cumene process ). Phenols are acidic and react with strong bases to form alkali-metal salts known as phenoxides. The most important reaction of phenol is its condensation (which produces water as a side effect) with formaldehyde. Commercially main derivatives from phenol are ; Bisphenol A ( > Polycarbonate and Epoxy Resins), Phenolic Resins ( > Moulding Binders, Insulation Wool), Cyclohexane ( > Caprolactam), Alkylphenols ( > Surfactants), Salicyclic Acid ( > Pharmaceuticals). Phenol is an important parent material in the production of thermosetting resins, drugs, dyes, pesticides, and explosives.