Organic Chemistry - Alcohol Reactions

Organic Compounds

• Carboxylic Compounds: Includes molecules with a carboxyl group (-COOH). Different functional groups connected to the carbon chain give them unique properties.
• Alcohols/Ethers: Characterized by the presence of the hydroxyl (-OH) group in alcohols, and the ether group (-O-) in ethers. Their structures and polarities (decreasing with additional methyl groups) influence their chemical behaviors. Steric hindrance is a factor that impacts their behavior.
• Hydrocarbons: Organic compounds composed solely of carbon and hydrogen.

Alcohols and Ethers

• Nomenclature: Alcohols and ethers are named according to the number of carbon atoms.
  • Examples: Methanol (CH₃OH), Ethanol (CH₃CH₂OH).
• Polarity: The polarity of alcohols and ethers decreases as the number of carbon atoms increases.

Preparation of Alcohols

• Hydration of Alkenes: Addition of water molecules to alkenes.
• Oxymercuration-demercuration: Two-step reaction using mercury reagents for alkene hydration.
• Nucleophilic Substitution: A process where a nucleophile substitutes a leaving group.

Reactions of Alcohols

• Reaction with Weakly Acid: Protonation of the O-H bond, creating a better leaving group.
• Alkoxide formation: Reaction of alcohols with strong bases.

Oxidation of Alcohols

• Mild Oxidative Reagent: Chemicals that can oxidize alcohols to aldehydes or ketones. These can be Reagents like PCC, or CrO3.
• Strong Oxidative Reagent: Oxidize alcohols to carboxylic acids
• Oxidizing Agents Examples: KMnO₄, H₂CrO₄, PCC.

Dehydration of Alcohol

• Elimination Reactions: Forms alkenes by removing water.

Preparation of Ethers

• Williamson Ether Synthesis: Nucleophilic substitution reaction.

Reactions of Ethers

• Cleavage of Ether: Reaction with strong acids like HI or HBr to break the C-O bonds.
• Hydration of Ethers: Reaction with strong acid to form alcohols and alkyl halide.

Carbonyl Compounds

• Aldehydes/Ketones: Contain the carbonyl group (C=O). Nomenclature follows the number of carbon atoms with specific functional groups.
• Oxidation of Alcohols Aldehydes and ketones are products of oxidizing alcohols (mild oxidation).
• Reduction of Carbonyl Compounds: Conversion of aldehydes and ketones to alcohols by using reducing agents such as LiAlH₄ or NaBH₄.

Reactions of Aldehydes and Ketones

• Nucleophilic Addition: Addition of nucleophiles to the carbonyl group.
• **Halogenation ** Addition of halogens (Cl₂ or Br₂) to the carbonyl group.
• Addition of Cyanide: Addition of cyanide to the carbonyl group.
• Addition of Grignard Reagents: Strong reducing reagent often used to obtain alcohols.
• Oxidation: Conversion to carboxylic acids.

Reactions of Carboxylic Acids and Derivatives

• Acyl Substitution: Nucleophilic substitution reactions.
• Hydrolysis: Splitting of the molecule by reacting with water.
• Reduction Conversion to alcohols or aldehydes
• Preparation of acyl chlorides: Reactions used to produce acyl chlorides.

Preparation of Acyl Chloride.

• Reactions of acyl chloride: Reactions to produce various compounds.

Aldol Condensation

• A condensation reaction: Combining two molecules by removing water.