0
$\begingroup$

I have seen this video about the hydrolysis of amides in order to convert them to a carboxylic acid. I understood how it works but I want to know how would someone physically do it in a lab.

I need to know the temperature needed, the time required for the reaction to happen, the reactants ratio and the process itself.

$\endgroup$

1 Answer 1

2
$\begingroup$

The answer, as with so much chemistry, is it depends. What substrate are you hydrolysing, is it a primary, secondary or tertiary amide? What else is in the molecule that you want to preserve?

Both acid and base hydrolysis require concentrated conditions and elevated temperature. There is a lab procedure here that uses sodium hydroxide in water at reflux to hydrolyse benzamide to benzoic acid. The standard cleavage of an acetamide protecting group to give amine plus acetic acid is overnight reflux in 2N HCl or KOH in MeOH at reflux ref here, for a benzamide protecting group it is 48h in 6N HCl or HBr in Acetic Acid at rt.

In my own experience a particularly resistant acetamide required 3 equivalents of KOH in refluxing ethylene glycol to hydrolyse.

$\endgroup$
2
  • $\begingroup$ Thank you for your answer! My amide is a primary amide and the rest of it's structure is formed out of benzenic rings, like benzamide. As in the conversion of benzamide into benzoic acid I need to replace the NH2 bond with an OH bond. Does this mean that the procedure from here is going to work for me as well? $\endgroup$ Commented Dec 28, 2018 at 11:32
  • $\begingroup$ That procedure should work for you. If it does not then try an acid procedure as used for a benzamide protecting group $\endgroup$
    – Waylander
    Commented Dec 28, 2018 at 12:15

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.