Esterification
Ethanol oxygen bonds to the acid carbonyl carbon, followed by proton transfer and water loss. The product joins a butanoyl fragment to an ethoxy group.
- Reagents
- Ethanol; H2SO4 catalyst
- Conditions
- Heat with acid catalyst; reversible equilibrium
- Reaction class
- Esterification
- Equation
- CH3CH2CH2COOH + CH3CH2OH <=> CH3CH2CH2COOCH2CH3 + H2O
Overview
Ethanol oxygen bonds to the acid carbonyl carbon, followed by proton transfer and water loss. The product joins a butanoyl fragment to an ethoxy group.
Transformation
Butanoic acid → Ethyl butyrate
- Equation
- CH3CH2CH2COOH + CH3CH2OH <=> CH3CH2CH2COOCH2CH3 + H2O
- Reactants
- Butanoic acid + Ethanol
- Products
- Ethyl butyrate + Water
- Reagents
- Ethanol; H2SO4 catalyst
- Environment
- Heat with acid catalyst; reversible equilibrium
- Reaction class
- Esterification
- Mechanism
- acid-catalysed nucleophilic acyl substitution
- Evidence level
- source-backed molecular example
Scope and limitations
- Scope
- Butanoic acid supplies the four-carbon acyl fragment; ethanol supplies two further carbons.
- Limitations
- Ethyl butyrate is ethyl butanoate, not butyl ethanoate. The two six-carbon esters have different connectivity.
Related reactions
- Aldehyde oxidation: Butanal → Butanoic acid
The hydrated aldehyde is oxidised to a carboxyl group. All four starting carbon atoms remain together in butanoic acid.
- Acid hydrolysis: Ethyl butyrate → Butanoic acid
Water attack and proton transfers permit the ethoxy fragment to leave as ethanol. Re-forming the carbonyl produces butanoic acid on the other branch.
- Acid hydrolysis: Ethyl butyrate → Ethanol
Water attack and proton transfers permit the ethoxy fragment to leave as ethanol. Re-forming the carbonyl produces butanoic acid on the other branch.
References
- Organic Chemistry: Reactions of Carboxylic AcidsJohn McMurry · OpenStax Organic Chemistry · 2023
Checked 2026-09-16. Supports the reaction pattern and mechanistic explanation; named examples apply that scope to existing molecular records without claimed experimental yields.