Hydrochloric Acid → 2-Acetamido-2,3-dimethylbutanoic acid

Reaction equation

[NH2:1][C:2]([CH3:9])([CH:6]([CH3:8])[CH3:7])[C:3]([OH:5])=[O:4].[C:10](OC(=O)C)(=[O:12])[CH3:11].Cl>[OH-].[Na+]>[C:10]([NH:1][C:2]([CH3:9])([CH:6]([CH3:8])[CH3:7])[C:3]([OH:5])=[O:4])(=[O:12])[CH3:11]

Participants

Procedure

To a stirred solution of 2-amino-2,3-dimethylbutyric acid (13.1 g) in 55 ml 2N NaOH maintained at 5° C is added simultaneously dropwise but separately 17 ml acetic anhydride and 95 ml 2N NaOH so that the pH of the solution is maintained at about 8.5. After stirring at room temperature for a further 1/2 hour, the mixture is acidified with concentrated HCl and the product, (±)-2-acetylamino-2,3-dimethylbutyric acid, removed by filtration, washed with cold water and air-dried. A sample recrystallized from acetonitrile had melting point 189°-190° C.