Synthesis of amides directly from carboxylic acids and hydrazines.

The method for amide bond synthesis described here utilizes carboxylic acids and hydrazines in the presence of a catalytic amount of ZnCl 2 . This is the first report that highlights the use of hydrazine as an amine partner for amide synthesis directly with carboxylic acids. Ammonia (gas) is the only by-product in this method. The methodology is simple and could help in the synthesis of peptides and natural product derivatives.