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Topic: estrification  (Read 5518 times)

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Offline firzzy87

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estrification
« on: July 17, 2006, 08:13:16 AM »
Why after estrification process , sodium bicarbonate was added in an ester solution ... If i m not mistake , ester is the mixture of  carboxylic acid and alcohol ???

Offline Albert

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Re: estrification
« Reply #1 on: July 17, 2006, 09:01:46 AM »
Esterification reaction is an equilibrium and an acid-catalyzed reaction.

With sodium bicarbonate you avoid your reaction going in the backward direction, neutralizing the acid catalyzer.

Offline HP

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Re: estrification
« Reply #2 on: July 17, 2006, 01:21:11 PM »
Be carefull with ading NaHCO3 because if you add excess it then at alkali pH hydrolysis ester most favorite...
xpp

Offline Yggdrasil

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Re: estrification
« Reply #3 on: July 17, 2006, 01:41:55 PM »
Sometimes you wash the organic reaction mixture with an aqueous solution of sodium bicarbonate after you perform a Fischer esterification.  If your ester is not water soluble and you used the organic acid in excess, the sodium bicarbonate solution will neutralize both your acid catalyst and organic acid.  Since the deprotonating the organic acid produces a charged carboxylate (which is more soluble in water than in organic solvent), washing with aqueous sodium bicarbonate serves to help isolate your product.

Offline victor

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Re: estrification
« Reply #4 on: July 17, 2006, 11:49:55 PM »
I think it's better to use a 2-step esterification process..by reacting acyl halyde with alcohol...then, there would be no backward reaction... ;D

Offline firzzy87

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Re: estrification
« Reply #5 on: July 18, 2006, 12:19:27 AM »
thanks for all this  :D

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