Additionally, Jencks et al suggested that the rate-determining step of this reaction is the dehydration of the initially hydrated benzaldehyde, which we have shown as the second transition state step. The lone pair of electrons from the terminal nitrogen (N-5 atom)facilitates the proton transfer and causes the newly formed -OH group on the tautomeric form of benzaldehyde to detach from the intermediate. As the O-atom within the intermediate is nucleophilic due to the presence of the lone pair in the newly formed -OH group, the hydroxide ion (OH-) acts as a base catalyst to initiate an intramolecular dehydration reaction with the E1cB mechanism. The C-8 atom from the benzaldehydesubsquently forms a C=N double bond with N-5 from the hydrazide,forming the respective hydrazone derivatives in Fig. . The detached hydroxide ion (OH-) is eliminated from the remaining H-6 atom from within the -NH2 group, forming H2O. Hydrazones and oximes are generally more hydrolytically stable than imines due to the α-effect from the lone pair of the heteroatom (N or O) adjacent to the sp2 hybridized nitrogen atom.