Synthesis of Ethyl Acetate


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This procedure could/should probably be scaled up...

Procedure

Ethyl ethanoate may also be prepared on a larger scale as follows. Add about 10ml of concentrated sulphuric acid to an equal volume of ethanol in a distillation flask (heat is evolved), together with a few pieces of porous pot to ensure smooth boiling later. Connect a condenser and a dropping funnel to the flask as shown in the diagram below and placein the dropping funnel 20ml of ethanol with an equal volume of ethanoic acid. Heat the oil bath to about 150°C and slowly add the ethanol-acid mixture. Ethyl ethanoate distills over. It will contain ethanol and ethanoic acid as impurities and these can be removed by shaking the distillate with sodium carbonate solution to remove the ethanoic acid and calcium chloride solution to remove the ethanol. The ethyl ethanoate can then be dried over fused calcium chloride and obtained pure by distillation.

 


[contributed by Mountain_girl]:

Mix 50ml (40g) EtOH and 50ml (52g) GAA thoroughly in a 250ml rbf and add slowly with cooling and shaking, 10ml (18.5g) of concentrated sulphuric acid. Ensure that the liquid is homogenous, then fit the flask with a reflux condenser and boil gently for 10min.
Now distil off about 2/3 of the mixture and then transfer the distillate to a separation funnel. Add about 25ml of 30% NaCO3 solution, cork the funnel and shake carefully in order to neutralise and remove the free acetic and sulphurous acids present in the crude ethyl acetate: much CO2 is evolved during the shaking, therefore release the pressure in the funnel at frequent intervals. Allow the two layers to separate, and carefully run off and reject the lower aqueous layer, ensuring that the NaCO3 solution is removed as completely as possible. Then prepare a solution of 25g anhydrous CaCl2 in 25ml water, add it to the ethyl acetate in the funnel and again shake vigorously. The CaCl2 solution removes any EtOH still present. Allow the mixture to separate and again remove the lower aqeous layer as completely as possible. Then run the ethyl acetate into a small conical flask, add a few lumps of granular CaCl2 and shake occasionally.
After about 20min when the liquid should be dry, filter it through a small fluted filter paper into a 100ml distillation flask attached to a condenser. Add some boiling chips and distill. Some ether is always formed as a byproduct and is carefully (i.e. slowly) distilled off as a preliminary and separate fraction boiling at 35-40°C.
Collect the portion of the distillate boiling at 74-79°C, rejecting a small fraction boiling immediately below this range. Yield 50g.
Ethyl acetate is a colourless liquid with b.p. 77°C and density 0.92g/ml and a pleasant apple-like odour, and is only slightly soluble in water.

References

[1] D. N Underwood and D.E. Webster, Chemistry, 4th Ed. p 457-458 (1975)
[2] Practical Organic Chemistry, F.G. Mann & B.C. Saunders, 4th Ed.,pg. 96