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Ethyl butanoate - 1H spectrum(bottom) and COSY spectrum (top)
After refluxing, disconnect the heating supply and allow the solution to cool to room temperature- you may cool it in a beaker of water. Transfer the reaction mixture to a 60 mL separatory funnel. Rinse the flask with 10 mL of water and transfer this to the separatory funnel, try to swirl the mixture. [CARE: when shaking mixtures, pressurization may occur, especially with the sodium bicarbonate extraction!] Cap the separatory funnel and shake, venting frequently, to mix the two layers. Allow the layers to separate and then drain and discard the lower aqueous layer. Next, wash the organic layer with 10 mL of saturated sodium bicarbonate. Finally, wash the organic layer with 10 mL of saturated aqueous sodium chloride. Dry the organic layer using anhydrous magnesium sulfate. Distill the final product to purify it and get a boiling point. Your product should distill between 50°C and 150°C. Put the receiver in an ice bath to help condense the product and reduce vapors. Take the mass of the distilled product, but you cannot calculate % yield.
1H NMR
13C NMR
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Ethyl butanoate - 1H spectrum(bottom) and COSY spectrum (top)
Reaction Procedure
You will be given a reaction flask that contains a carboxylic acid and an alcohol. Carefully add 1.0 mL (1.84 g) conc. sulfuric acid. The acid should be added dropwise with swirling. Add a boiling chip and attach a water cooled condenser. Reflux the solution for 60-75 minutes. During the reflux period the solution may turn cloudy and a second layer may form. If it does, this is your product. Not all the reaction mixtures will form two layers. Some mixtures will be colorless, others will be yellow or even dark brown.After refluxing, disconnect the heating supply and allow the solution to cool to room temperature- you may cool it in a beaker of water. Transfer the reaction mixture to a 60 mL separatory funnel. Rinse the flask with 10 mL of water and transfer this to the separatory funnel, try to swirl the mixture. [CARE: when shaking mixtures, pressurization may occur, especially with the sodium bicarbonate extraction!] Cap the separatory funnel and shake, venting frequently, to mix the two layers. Allow the layers to separate and then drain and discard the lower aqueous layer. Next, wash the organic layer with 10 mL of saturated sodium bicarbonate. Finally, wash the organic layer with 10 mL of saturated aqueous sodium chloride. Dry the organic layer using anhydrous magnesium sulfate. Distill the final product to purify it and get a boiling point. Your product should distill between 50°C and 150°C. Put the receiver in an ice bath to help condense the product and reduce vapors. Take the mass of the distilled product, but you cannot calculate % yield.
1H NMR
13C NMR
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Type: 13C
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