Synthesis of EstersSynthesis of Esters

Nucleophilic Acyl SubstitutionNucleophilic Acyl Substitution

Uses of EstersUses of Esters

Used in perfume Used in perfume makingmaking

Used as food taste Used as food taste enhancersenhancers

Used as solvent of Used as solvent of other compoundsother compounds

Used as fuelUsed as fuel

ReagentsReagents

Carboxylic AcidCarboxylic Acid AlcoholAlcohol

ProcedureProcedure

Measure prescribed Measure prescribed amts of reagents in a amts of reagents in a round bottom quick fit round bottom quick fit flaskflask

Add 2-3 drops of conc. Add 2-3 drops of conc. Sulfuric acidSulfuric acid

Reflux for 45-60 Reflux for 45-60 minutesminutes

Procedures cont’d.Procedures cont’d.

Transfer cooled mixture to Transfer cooled mixture to a separatory funnela separatory funnel

Rinse flask with water then Rinse flask with water then add to sep. funnel until add to sep. funnel until volume is twice that of volume is twice that of organic layerorganic layer

Shake then allow to stratifyShake then allow to stratify Add NaCl soln to hastes Add NaCl soln to hastes

separationseparation Add NaHSO4 to neutralize Add NaHSO4 to neutralize

acidacid

Procedures cont’dProcedures cont’d

Collect organic layer Collect organic layer and dry with and dry with anhydrous Sodium anhydrous Sodium SulfateSulfate

Distill using dry Distill using dry glassware glassware (OPTIONAL)(OPTIONAL)

Overall ReactionOverall Reaction

MechanismMechanism

Nucleophilic Acyl Nucleophilic Acyl SubstitutionSubstitution

note:note:

Esterification is equilibrium sensitive thus the Esterification is equilibrium sensitive thus the need for excess reagentsneed for excess reagents

Esters hydrolyze in the presence of waterEsters hydrolyze in the presence of water