Random
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Making esters without sulfuric acid
I don't have any sulfuric acid and I would like to make esters. I read somewhere that lewis acids can do it instead of sulfuric acid. Would iron(iii)
chloride form ester with benzoic acid in brandy (40-70% alcohol) to form ethyl benzoate?
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DDTea
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In principle, FeCl<sub>3</sub> should work as a catalyst. The purpose of the lewis acid in Fischer esterification is to stabilize the
carboxylic acid as an oxonium ion. FeCl<sub>3</sub> should form a complex with the said oxonium ion, stabilizing the charge on the oxygen
atom and activating the acid for nucleophilic attack by the alcohol.
As far as doing the reaction in brandy, it may have too much water for Fischer esterification to be feasible since the equilibrium is unfavorable
enough as it is.
"In the end the proud scientist or philosopher who cannot be bothered to make his thought accessible has no choice but to retire to the heights in
which dwell the Great Misunderstood and the Great Ignored, there to rail in Olympic superiority at the folly of mankind." - Reginald Kapp.
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entropy51
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Sodium bisulfate, sold as "pH Down" for swimming pools, will work as a catalyst for some esterifications. Here is one example. There are others.
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12AX7
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Also, FeCl3 hydrate is not a lewis acid, it's already "reacted" with water. You have to use anhydrous material. If nothing else, you'll need to
distill your brandy up to near absolute (98%) to get that to work.
Tim
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DJF90
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Fe (III) sulfate.xH20 works excellently for catalysing the esterification of aliphatic acids and di-acids. Toluene and a dean stark apparatus are
necessary though. Theres a nice paper on it, yields all look over 90% IIRC.
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Random
International Hazard
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I have some potassium metabisulfite and in reaction with water should make so2 and potassium bisulfite which should oxidize into khso4. Could I use
that to make ester from brandy and benzoic acid? I read in king's chemistry survival guide the preparation that uses 30% sulfuric acid, ethanol
(possible vodka) and only 9% vinegar to make ethyl acetate.
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