Question

Propose a mechanism for the rearrangement that converts an -hydroxyimine to an α -aminoketone in the presence of a trace amount of acid (page 960).

Short answer

Tautomers constitute isomers that vary in moving a hydrogen atom from one atom to another. The chemical equilibrium between the keto form and an enol form in organic chemistry is termed keto-enol tautomerism.

Tautomers are present between the keto and enol forms.

Step-by-step solution

Keto-enol tautomerism

Tautomers constitute isomers that vary in moving a hydrogen atom from one atom to another. The chemical equilibrium between the keto form and an enol form in organic chemistry is termed keto-enol tautomerism.

Tautomers are present between the keto and enol forms.

 Step 2: Propose a mechanism for the rearrangement that converts an -α hydroxyimine to an α -aminoketone in the presence of a trace amount of acid

In the blood, glucose reacts with group of hemoglobin to form an imine. This imine is converted into a more stable alpha-amino ketone by rearrangement. In the mechanism, the first step is the formation of enolate ion by the attack of the base.

The second step is the protonation of the enolate ion. The third step is the tautomerism to produce the product. The mechanism is given below.