Organic Chemistry: Alcohols and Phenols

Alcohols and Phenols

• Alcohols are organic compounds containing a hydroxyl (-OH) group attached to a carbon atom.
• Phenols are aromatic compounds containing a hydroxyl (-OH) group bonded directly to an aromatic ring.

Types of Alcohols

• Methanol (methyl alcohol)
• Ethanol (ethyl alcohol)
• 1-propanol (n-propyl alcohol)
• 2-propanol (isopropyl alcohol)
• 1-butanol (n-butyl alcohol)
• 2-butanol (sec-butyl alcohol)
• 2-methyl-1-propanol (isobutyl alcohol)
• 2-methyl-2-propanol (tert-butyl alcohol)
• 2-propen-1-ol (allyl alcohol)
• Cyclohexanol (cyclohexyl alcohol)
• Phenylmethanol (benzyl alcohol)

Types of Phenols

• Phenol
• p-chlorophenol
• 2,4,6-tribromophenol
• m-hydroxybenzoic acid
• p-hydroxybenzaldehyde
• p-nitrophenol
• 2,4-dinitrophenol

Physical Properties of Alcohols

• Boiling Point: Increases with increasing molecular weight due to stronger intermolecular forces
• Solubility: Low molecular weight alcohols are completely miscible with water due to hydrogen bonding; as the carbon chain lengthens, solubility decreases.
• Examples of boiling points and solubility of alcohols are listed in Table 7.1

Acidity of Alcohols and Phenols

• Alcohols are weakly acidic and phenols are more acidic because of resonance stabilization.

Reactions of Alcohols

• Reaction with sodium metal: Alcohols react with sodium metal to produce hydrogen gas and sodium alkoxide.
• Formation of alkyl halides: Alcohols react with halogen acids (HX) to form alkyl halides via SN1 or SN2 mechanisms
• Oxidation Primary alcohols can be oxidized to aldehydes and then to carboxylic acids; secondary alcohols are oxidized to ketones.
• Various oxidizing agents like K₂Cr₂O₇, H₂SO₄, CuO, Jones' reagent and PCC are used

Reactions of Phenols

• Reaction with nitric acid: Phenols react with dilute nitric acid to form nitrophenols, and with concentrated nitric acid to form trinitrophenol (picric acid).
• Reaction with Bromine: Phenol reacts with Bromine to form 2,4,6-tribromophenol

Thiols

• Similar to alcohols, but with a sulfur atom instead of an oxygen.

This quiz covers the fundamental concepts related to alcohols and phenols, including their structures, types, and physical properties. Test your knowledge on various alcohols like ethanol and phenol derivatives. Ideal for students studying organic chemistry.