Introduction
In this weeks lab each group is assigned an unknown alcohol and an unknown carboxylic acid for testing. Each group then synthesizes an unknown ester from a Fisher Esterification reaction of the given unknown. Once an ester product is obtained, 1H and 13C NMR, boiling point, and smell testes are run on the final product in order to identify all the given unknowns.
Procedures
The first step of this week’s lab was to mix 3mL of the unknown alcohol and 6mL of the unknown carboxylic acid in a microwave reaction vessel. To the mixture, 0.75mL of concentrated sulfuric acid was added and the solution was immediately stirred. Once the solution was stirred, the cap was placed on the reaction vessel, which was put into the microwave for heating. Next, 40mL of 3M sodium hydroxide was chilled in an ice bath, and then the extraction apparatus was constructed. Once the microwave was done, the vessel was rinsed with 5mL of water, which was poured into the separatory funnel. Then cold sodium hydroxide was then added portion wise to the separatory funnel and the funnel was swirled. Next, 10mL of dichloromethane was added to the separatory funnel, which was then inverted and vented toward the back of the fume hood. Once mixing was complete, the organic layer was separated into …show more content…
Based on the NMR tests that were run, the results were very consistent to the NMRs of isopentyl acetate. Based on these charts, we concluded that our unknown alcohol was isopentyl alcohol and the unknown carboxylic acid was acetic acid. The boiling point of the experimental product was 140.2°C, which supports the conclusion of isopentyl acetate because that has a boiling poing of 142°C. The main source of error for this week’s lab was leaving the product to dry for 2 full weeks. This caused my groups product to completely dry up, making us join up with another group to use their
In this weeks lab each group is assigned an unknown alcohol and an unknown carboxylic acid for testing. Each group then synthesizes an unknown ester from a Fisher Esterification reaction of the given unknown. Once an ester product is obtained, 1H and 13C NMR, boiling point, and smell testes are run on the final product in order to identify all the given unknowns.
Procedures
The first step of this week’s lab was to mix 3mL of the unknown alcohol and 6mL of the unknown carboxylic acid in a microwave reaction vessel. To the mixture, 0.75mL of concentrated sulfuric acid was added and the solution was immediately stirred. Once the solution was stirred, the cap was placed on the reaction vessel, which was put into the microwave for heating. Next, 40mL of 3M sodium hydroxide was chilled in an ice bath, and then the extraction apparatus was constructed. Once the microwave was done, the vessel was rinsed with 5mL of water, which was poured into the separatory funnel. Then cold sodium hydroxide was then added portion wise to the separatory funnel and the funnel was swirled. Next, 10mL of dichloromethane was added to the separatory funnel, which was then inverted and vented toward the back of the fume hood. Once mixing was complete, the organic layer was separated into …show more content…
Based on the NMR tests that were run, the results were very consistent to the NMRs of isopentyl acetate. Based on these charts, we concluded that our unknown alcohol was isopentyl alcohol and the unknown carboxylic acid was acetic acid. The boiling point of the experimental product was 140.2°C, which supports the conclusion of isopentyl acetate because that has a boiling poing of 142°C. The main source of error for this week’s lab was leaving the product to dry for 2 full weeks. This caused my groups product to completely dry up, making us join up with another group to use their