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Phenols
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In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of a hydroxyl group (-O H) attached to an aromatic hydrocarbon group. The simplest of the class is phenol (C6H5OH).
Although similar to alcohols, phenols have unique properties and are not classified as alcohols (since the hydroxyl group is not bonded to a saturated carbon atom).

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In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of a hydroxyl group (-O H) attached to an aromatic hydrocarbon group. The simplest of the class is phenol (C6H5OH).
Although similar to alcohols, phenols have unique properties and are not classified as alcohols (since the hydroxyl group is not bonded to a saturated carbon atom). They have relatively higher acidities due to the aromatic ring's tight coupling with the oxygen and a relatively loose bond between the oxygen and hydrogen. The acidity of the hydroxyl group in phenols is commonly intermediate between that of aliphatic alcohols and carboxylic acids (their pKa is usually between 10 and 12). Loss of a positive hydrogen ion (H+) from the hydroxyl group of a phenol forms a negative phenolate ion.
Some phenols are germicidal and are used in formulating disinfectants. Others possess estrogenic or endocrine disrupting activity.
Synthesis of phenols
Several laboratory methods for the synthesis of phenols:
- by an ester rearrangement in the Fries rearrangement
- by a rearrangement of N-phenylhydroxylamines in the Bamberger rearrangement
- by hydrolysis of phenolic esters or ethers
- by reduction of quinones
- by replacement of an aromatic amine by an hydroxyl group with water and sodium bisulfide in the Bucherer reaction
- by hydrolysis of diazonium salts
- by oligomerisation with formaldehyde + base catalysed reaction with epichlorohydrine to epoxi resin components
- by reaction with acetone/ketones to e.g. Bisphenol A, an important monomer for resins, e.g. polycarbonate(PC), epoxi resins
- by a rearrangement reaction of dienones in the dienone phenol rearrangement :
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Reactions of phenols
Phenols react in a wide variety of ways.
- Phenolate anions (deriving from phenols by the loss of H+) can act as ligands towards metal cations
Phenolic compounds
- For a full list, see :Category:Phenols
Adverse health effects of some phenols
Some of the above substances are related to endocrine-disruptive chemicals.
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