Diethylenetriamine is effective for the direct cleavage of unactivated carbamates and ureas without additional reagents and catalysts. Various carbamates and ureas were cleaved to afford products in good yield, and the reactions were not affected by air or moisture. Unique chemoselective cleavage of carbamate and urea in the presence of amides was also achieved.

Hydrazinolysis of unactivated amide bonds is significantly accelerated by the addition of ammonium salts. The reactions proceed at 50-70 °C to give amines with broad substrate scope that outperforms existing amide bond cleavage reactions. Application to peptide and amino sugar derivatives is also demonstrated.

A study of ammonium salt-accelerated hydrazinolysis of unactivated amides is described. We first studied the reaction mechanism by kinetic experiments and DFT calculations and found that cooperation of the hydrazinium salt and hydrazine is important for promoting the cleavage of unactivated amides. Next, we applied the reaction to a microwave flow process, and the amine products were isolated on a multigram scale.