Sciencemadness Discussion Board

Catalysts for Fischer Esterification

achem500 - 2-8-2012 at 21:22

Is sulfuric acid the only acid that can be used as a catalyst in a Fischer esterification? Any help is appreciated.

kavu - 2-8-2012 at 22:58

No, many acids are able to activate carbonylic oxygen to make it more electrophilic. Protonation or Lewis acid coordination can be used. Commonly employed proton donors are phosphoric acid, dry HCl, H2SO4, toluenesulfonic acid, acidic ion exchange resins such as Amberlyst 15. Numerous Lewis acids have been used, a more comprehensive list can be found from http://www.organic-chemistry.org/namedreactions/fischer-este....

An OTC alternative for these reagents is the good old sodium bisulfate.

[Edited on 3-8-2012 by kavu]

achem500 - 3-8-2012 at 00:13

Thanks! I take it that I should use an equivalent amount during a future reaction? or should I use an excess of one reagent?

Also, how could I obtain dry HCl? Straight HCl gas or very concentrated aqueous solution? Does water upset a Fischer esterification?

Thanks a bunch

Nicodem - 3-8-2012 at 07:28

https://www.sciencemadness.org/whisper/viewthread.php?tid=13...

achem500 - 3-8-2012 at 13:44

Thank you

Housane - 4-1-2020 at 14:50

Am I right that sodium bisulfite is a direct weight for weight replacement

DavidJR - 4-1-2020 at 15:43

Quote: Originally posted by Housane  
Am I right that sodium bisulfite is a direct weight for weight replacement


Replacement for what?

Abromination - 4-1-2020 at 18:21

There are a great many posts on this already. Sulfuric acid is the best one, all though there are many others. Boric acid does not work, there are a lot of threads that say it may. Sulfonated styrene works, i think tosylic acid works, and I have heard that anhydrous sodium bisulfate works. Do some research to find what you need.

Tsjerk - 5-1-2020 at 09:05

Quote: Originally posted by Abromination  
There are a great many posts on this already. Sulfuric acid is the best one, all though there are many others. Boric acid does not work, there are a lot of threads that say it may. Sulfonated styrene works, i think tosylic acid works, and I have heard that anhydrous sodium bisulfate works. Do some research to find what you need.


Sulfonated styrene has the benefit of being a solid, making workup easier.

Abromination - 5-1-2020 at 10:55

Quote: Originally posted by Tsjerk  
Quote: Originally posted by Abromination  
There are a great many posts on this already. Sulfuric acid is the best one, all though there are many others. Boric acid does not work, there are a lot of threads that say it may. Sulfonated styrene works, i think tosylic acid works, and I have heard that anhydrous sodium bisulfate works. Do some research to find what you need.


Sulfonated styrene has the benefit of being a solid, making workup easier.

Speaking of which, I tore open a brita filter to remove the resin and found it to be mixed pretty evenly with the activated carbon. The beads are also pretty small. In going to try to separate them but I’m not expecting much.

9BAAEA70-91AE-470D-A748-4E4E552CBF7C.jpeg - 2.7MB