[xshadow]

 Hi

If I add NaOH in a primary -amide solution   RCONH₂


What reaction  will it happen?

A) the basic hydrolysis  of amide  to form carboxylic  ac8d
B) the deprotonation of a N-H bond ?

Are amide hydrogen acid?
I think a bit...(i thought at the acidity of C-H , α  to carbonyl


Thanks

[AWK]

https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Book%3A_Basic_Principles_of_Organic_Chemistry_(Roberts_and_Caserio)/24%3A_Organonitrogen_Compounds_II-_Amides%2C_Nitriles%2C__Nitro_Compounds/24.04%3A_Hydrolysis_of_Amides

You can remove proton from amide using  a very strong base eg NaH, NaNH₂ ... in anhydrous conditions.

[Babcock_Hall]

IIRC basic hydrolysis of an amide is a slow reaction that requires elevated temperatures.

[xshadow]

Hi,

...because in my textbook (org1)I've seen that NaOH can give hydrolysis with NaOH


But in org2 I've seen hofmann degradation/ transposition where NaOH  (+Br₂)deprotonates a N-H bond instead of attacking the carbonyl

Thanks

[Babcock_Hall]

Basic hydrolysis of proteins is occasionally performed, and the reason is that acid hydrolysis, the more common method by far, of proteins destroys the amino acid tryptophan.  I don't know the exact conditions, however.  Most peptide bonds have an NH group (proline being the exception).

[kriggy]

Hi,

...because in my textbook (org1)I've seen that NaOH can give hydrolysis with NaOH


But in org2 I've seen hofmann degradation/ transposition where NaOH  (+Br₂)deprotonates a N-H bond instead of attacking the carbonyl

Thanks

Those are two different reaction. Amide hydrolysis is certainly possible using NaOH. I used that to hydrolyze secondary formamide (At room temperature) or primary acetamide (reflux).
Hoffman degradation is different reaction when the hydroxide and bromine form NaBrO which brominates the amide and in basic media generates nitrene which undergoes rearrangement followed by decarboxylation to yield amine

[phth]

Yes,
Base hydrolyzes amide bonds even though they can be deprotonated. However, it is slow like days at elevated pH and physiological temp.

[Disjointcape]

While the acid-base reaction would be very fast, it would be in equilibrium. Amides can be considered acidic, pKa ≈ 17, water is more acidic, pKa = 15.6. The values are close enough that a portion of the amides will be deprotonated, but in protic solvents the solvent can help facilitate the fast proton exchange and stabilize the amide, even as a negative ammonia leaving group during hydrolysis. Another important point is the final product of the carboxylic acid would be deprotonated in the basic solution, which would prevent the back reaction of the aminolysis, also driving the reaction forward.