Concepts about Alcohols and Phenols

Alcohols

• Definition: Organic compounds containing a hydroxyl group (-OH) bonded to a carbon atom of an alkyl or aryl group.
• Classification: Primary (1°), secondary (2°), or tertiary (3°) alcohols based on the number of carbon atoms bonded to the carbon atom bearing the hydroxyl group.
• Properties:
  • Hydrogen bonding: Capable of forming hydrogen bonds with themselves and other molecules.
  • Boiling points and solubility: Higher boiling points and solubility in water compared to hydrocarbons of similar molecular weight.
• Reactions:
  • Substitution: Replacement of the hydroxyl group with other functional groups.
  • Elimination: Loss of a water molecule to form an alkene.
  • Oxidation: Conversion of the hydroxyl group to a carbonyl group.
  • Esterification: Reaction with carboxylic acids to form esters.
• Examples:
  • Ethanol (CH3CH2OH): Simplest alcohol, produced by fermentation of sugars, main component of alcoholic beverages.
  • Methanol (CH3OH): Toxic alcohol, used as a fuel, solvent, and in chemical production.
  • Isopropyl alcohol [(CH3)2CHOH]: Commonly used as a rubbing alcohol and disinfectant.
  • Glycerol (C3H5(OH)3): Trihydroxy alcohol, component of fats and oils, used in cosmetics, personal care products, and pharmaceuticals.

Phenols

• Definition: A class of aromatic alcohols that have a hydroxyl group bonded to a benzene ring.
• Properties:
  • Acidity: More acidic than alcohols due to the electron-withdrawing effect of the benzene ring.
  • Electrophilic aromatic substitution: Undergo electrophilic aromatic substitution reactions, such as halogenation, nitration, and sulfonation.
• Examples:
  • Phenol (C6H5OH): Disinfectant, preservative, used in the production of various chemicals and polymers.
  • Cresol (CH3C6H4OH): Similar properties and uses to phenol.
  • Thymol (C10H14OH): Natural phenol found in thyme, antiseptic, and antifungal properties.