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Citric acid has both alcohol and carboxylic acid groups, so could it "esterify" with the other citric acid molecules in solution?

I notice that it is a tertiary alcohol. I don't suppose that would significantly hinder esterification, would it? Then again, it's not as if citric acid simply polymerizes with other citric acid molecules in solution anyway.

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    $\begingroup$ Tertiary alcohols tend to lose water and produce alkenes, if you press a little too hard. Obtaining the ester you want seems to be possible, but not simple. $\endgroup$ – Ivan Neretin Nov 22 '17 at 5:05
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    $\begingroup$ The answer is yes, but you can't make it by normal means because citric acid decomposes to easily. All I did was search on Google for "poly citric acid." You'll find stuff like this: sciencedirect.com/science/article/pii/S0011916416301813 $\endgroup$ – Zhe Nov 22 '17 at 23:33
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The esterification of carboxylic acids with tertiary alcohols usually occurs by an SN1 mechanism wherein the oxygen of the alcohol is protonated and a tertiary carbocation is formed. It in turn reacts with the carboxylic acid to form the tertiary ester. The hydroxyl group in citric acid, while tertiary, is alpha to a carboxyl group. A cation alpha to a carboxyl group (-CO2H) is a destabilized entity. This mechanism would be precluded. Traditional Fischer esterification is likely sluggish owing to steric hinderance.

SN1 Mechanism

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