Phenols

Jump to: navigation, search

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).

Phenol - the simplest of the phenols.

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 tightly 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 comprised 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:

The dienone phenol rearrangement

Reactions of phenols

Phenols react in a wide variety of ways.

Oxone Phenol Dearomatization

Phenolic compounds

For a full list, see Category:Phenols
Phenol the parent compound, used as an disinfectant and for chemical synthesis
BHT (butylated hydroxytoluene) - a fat-soluble antioxidant and food additive
Capsaicin the pungent compound of chilli peppers
Bisphenol A and other bisphenols produced from ketones and phenol / cresol
Chavibetol from betel, used as a flavouring
Cresol found in coal tar and creosote
Estradiol estrogen - hormones
Eugenol the main constituent of the essential oil of clove
Gallic acid found in gallnuts
Guaiacol (2-methoxyphenol) - has a smokey flavor, and is found in roasted coffee, whisky, and smoke
4-Nonylphenol a breakdown product of detergents and nonoxynol-9
Orthophenyl phenol a fungicide used for waxing citrus fruits
Picric acid (trinitrophenol) - an explosive material
Phenolphthalein pH indicator
Polyphenol e.g. flavonoids and tannins
Raspberry ketone a compound with an intense raspberry smell
Serotonin / dopamine / adrenaline / noradrenaline natural neurotransmitters
Thymol (2-Isopropyl-5-methyl phenol) - an antiseptic that is used in mouthwashes
Tyrosine an amino acid
Xylenol -


Medicinals

Cannabinoids the active constituents of cannabis
Diethylstilbestrol a synthetic estrogen with a stilbene structure
L-DOPA a synthetic estrogen with a stilbene structure
Methyl salicylate the major constituent of the essental oil of wintergreen
Propofol a short-acting intravenous anesthetic agent
Psilocin a hallucinogenic alkaloid of Psilocybe mushrooms
Salicylic acid a plant hormone used for its analgesic, antipyretic and anti-inflammatory properties, also a precursor compound to Aspirin
Trichlorophenylmethyliodosalicyl the main component of TCP, an antiseptic.


References

  1. related to quinones, see for example the Zincke-Suhl reaction
  2. Advanced organic Chemistry, Reactions, mechanisms and structure 3ed. page Jerry March ISBN 0-471-85472-7
  3. p-tert-butylcalix[8]arene, Organic Syntheses, CV 8, 80 Article
  4. 2,4-Hexadienedioic acid, monomethyl ester, (Z,Z)- Organic Syntheses, Coll. Vol. 8, p.490 (1993); Vol. 66, p.180 (1988) Article
  5. 2,5-Cyclohexadiene-1,4-dione, 2,3,5-trimethyl Organic Syntheses, Coll. Vol. 6, p.1010 (1988); Vol. 52, p.83 (1972) Abstract.
  6. Oxidative De-aromatization of para-Alkyl Phenols into para-Peroxyquinols and para-Quinols Mediated by Oxone as a Source of Singlet Oxygen M. Carmen Carreño, Marcos González-López, Antonio Urbano Angewandte Chemie International Edition Volume 45, Issue 17 , Pages 2737 - 2741 2006 Abstract

cs:Fenoly da:Fenoler de:Phenole et:Fenoolid it:Fenoli ko:페놀류 mk:Фенол (класа) he:פנול sk:Fenoly


Linked-in.jpg