i chem synthesis of esters
Post on 21-Oct-2014
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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