tomatl
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Ethyl Acetate from Absolute Ethanol, Anhydrous Sodium Acetate, and Concentrated Sulfuric Acid
There are already several threads on esterification. This topic deserves its own because of its specialized nature.
While considering the difficulty of obtaining glacial acetic acid and the complexity of including a dehydrating column in a reflux setup, the
following procedure came to mind. Suspend a 500 ml boiling flask in an ice bath. Add 60.0 ml absolute ethanol. Add 65.6 g powdered anhydrous sodium
acetate. Add 30.0 ml 98% aqueous sulfuric acid dropwise, stirring frequently. Reflux in 90 degree Celsius water bath for 45 minutes. Optionally use a
magnetic stir bar during reflux. Wash three times with weak sodium carbonate aqueous solution. Optionally distill.
The idea is that the sulfuric acid will react (as soon as it is added) with the sodium acetate to form both glacial acetic acid and anhydrous sodium
sulfate. The acetic acid will go on to react with the ethanol during reflux, the aprox 10 ml excess sulfuric acid will catalyze that reaction, and the
sodium sulfate will dehydrate water that is formed during the esterification to keep the equilibrium favorable.
Do you think this is a good idea? This would be my first esterification, so I figured I should reduce the number of steps as much as possible. My main
concern is that the sodium sulfate will not do its job properly if sitting at the bottom of the reaction mixture. For some reason, most put their
dehydrating agents in a little column that makes the whole condensation route much more complicated. I wish to avoid this if possible.
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Finnnicus
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I have been wondering... How essential is the catalyst? By definition the reaction proceeds without it... therefore NaHSO4 could be used instead of
sulfuric acid?
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tomatl
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| Quote: |
therefore NaHSO4 could be used instead of sulfuric acid?
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That is an excellent suggestion. I hadn't heard that sodium bisulfate could also catalyze esterification, but this paper (reliable?) agrees. Has anyone successfully catalyzed an esterification with sodium bisulfate?
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