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Isopentyl (Isoamyl) Acetate Synthesis and Extraction

12.0 g of isopentyl alcohol mixed with 20 mL glacial acetic acid and 1.2 mL of H2SO4. This is refluxed for an hour. Must use 20 mL of diethyl ether as the extraction solvent. What is the procedure for the extractions (to MAXIMIZE THE YIELD) and volumes? (i.e. How much water, NaCl, sodium bicarbonate and in what order)?

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In this experiment, we will prepare an ester, according to the reaction below. When combined in the presence of acid and heated, a water molecule is formed from the OH in each molecule, leaving a bridge over oxygen. The resultant compound is an ester.

Pour 15 mL (density 0.813g/mL) of isopentyl alcohol (also called isoamyl alcohol or 3-methyl-l-butanol) and 20 mL (density 1.049g/mL) of glacial acetic acid into a 100-mL round-bottomed flask. Cool the round bottom flask in ice for 5 minutes. Carefully add 1.2 mL of concentrated sulfuric acid to the contents of the flask, with swirling. Add two boiling stones to the mixture.
Assemble a reflux apparatus. Bring the mixture to a boil with a heating mantle. Heat the mixture under reflux for 1 hour. Remove the heating source and allow the mixture to cool for 2 minutes.
Pour the cooled mixture into a beaker filled approximately with 50g of ice (100 mL in beaker). Add the solution into a separatory funnel. Rinse the reaction flask with 10 mL of cold water and pour the rinsing into the separatory funnel. Add about 10 mL of diethyl ether. Stopper the separatory funnel and shake it several times (remember to vent the separatory funnel regularly!). Separate the lower aqueous layer from the upper organic layer into a labeled ...

Solution Summary

A full procedure for the reaction of acetic acid and isopentyl (isoamyl) alchohol forming isopentyl (isoamyl) acetate is provided in detail.