AbstractThis article deals with the kinetics of decomposition of four isomers: NCl‐(L)‐2‐Aminohexanoic acid, NCl‐(L)‐Leucine, NCl‐(L)‐Isoleucine, and NCl‐(L)‐tert‐Leucine, in mild acid and basic aqueous solution. An alternative mechanism for this process which takes place through a nitrenium‐like ion transition state is proposed. This mechanism is in consonance with the experimental data and with those available from the literature