N-Acetylation of methyl hydrazones with acetic acid in presence of PdCl₂

Abstract

Organic compounds such as acetic anhydride or acetyl chloride are generally used to form amide bonds by the acetylation of a nitrogen atom. However, it is not possible to use this traditional method for hydrazine derivatives. In this article, a new synthesis method has been developed for the formation of a new amide bond via the acetylation of methyl hydrazones with acetic acid. In the development of this unprecedented synthesis method, more than one catalyst was used as the Lewis acid. PdCl₂ was identified as the most suitable catalyst for this reaction. In addition, more than one solvent experiment was carried out for the optimization of this method and experiments were carried out to provide the most optimal conditions for catalyst loading. In addition, the applicability of this method to various hydrazone derivatives was tested. The structures of nine new amide bond-containing acetylated methyl hydrazones prepared by this synthesis method were elucidated using 1D-NMR, 2D-NMR, LCMS and X-Ray.

Graphical Abstract

Keywords:

• Acetylation
• amidation
• Lewis acid
• N-Methyl hydrazone
• PdCl₂

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supporting Information Summary

Supporting Information is included in full experimental detail (1H-NMR, 13C-NMR spectra, LC-MS, IR). This material can be found via the “Supplementary Content” section of this article’s webpage.

Additional information

Funding

This work was supported by the Van Yuzuncu Yil University under Grant [FBA-2022-10288].