Ethyl acetoacetate is subject to keto-enol tautomerism. Intermediate 2 then reacts via a tautomerism and dehydration to the aryldiazonium cation 3. The tautomerization often takes the form of keto-enol tautomerism. The enamine-imine tautomerism may be considered analogous to the keto-enol tautomerism. Triazenes derived from primary amines engage in tautomerism. Protonation leads through keto-enol tautomerism to the saturated carbonyl compound. This lactam lactim tautomerism can also be exhibited in many related compounds. It is distinct from prototropic tautomerism, and involves processes with rapid reorganisation of bonding electrons. The Keto-enol tautomerism strongly depends on the solvent used for the experiments. The concept of tautomerizations is called tautomerism. Prototropic tautomerism may be considered a subset of acid-base behavior. Then, keto-enol tautomerism occurs, resulting in the desired product. N-Substituted isoindoles do not engage is tautomerism and are therefore simpler to study.