Finally, we explored transformations of the alkynylated azapeptides. Hydration of the alkyne using PTSA afforded the corresponding amide moiety 6 bearing an α-silyl group. To the best of our knowledge, acylation of azaglycine has not been reported so far. For instance, chloroacetyl chloride has been shown to react with the hydrazone C=N bond. 5-Cyclization of the second nitrogen of the urea onto the alkyne afforded the product 7 in 63%. Similar cyclic scaffolds have been shown to induce -turn conformations in peptides. This type of cyclized product could only be observed as traces (<5%) during the formation of alkynylated azapeptides, which proceeded at lower reaction temperature with a shorter reaction time. Attempts to deprotect the TIPS substituted product 4a showed that the resulting free alkyne was too unstable to be purified. To circumvent this issue, the unsubstituted alkyne was directly engaged in a copper catalyzed alkyne-azide cycloaddition affording triazole 8 in 76% yield over 2 steps. Furthermore, N-terminus deprotection using hydroxylamine afforded the free hydrazide 9 as the TFA salt in 32% isolated yield after purification by reverse-phase HPLC. In summary, we have developed conditions to perform the alkynylation of azadipeptides using EBX reagents and an inexpensive copper catalyst. The reaction is selective to the nitrogen of the azaglycine residue and tolerate a large variety of amino acids affording the desired alkynylated azadipeptides in moderate to good yields. The transformation is not limited to silyl protected alkynes and both aryl and alkyl acetylenes can be transferred. The products could be further functionalized using classical alkyne reactivity affording different azadipeptide derivatives.