Nucleophilic Catalysis of Hydrazone Formation and Transimination:  Implications for Dynamic Covalent Chemistry DirksenAnouk DirksenSjoerd HackengTilman M. DawsonPhilip E. 2006 Aniline accelerates hydrazone formation and transimination through nucleophilic catalysis. To demonstrate the method, unprotected peptides are reacted and then scrambled using a hydrazone reaction under conditions relevant for biological applications. The strong enhancement in the rate of hydrazone equilibration broadens the scope of this stable imine in the field of dynamic covalent chemistry.