反应详情

A mixture containing 5.0 g methyl 2-formylbenzoate [C. Brown and M. V. Sargent, J. Chem. Soc. (C), 1818 (1969)] and 4.0 g 2-amino-2,3-dimethylbutyramide and 50 mg p-toluenesulfonic acid in 100 mL toluene is heated under reflux under a Dean-Stark water separator for three hours. The mixture is filtered and concentrated in vacuo. The residue crystallizes on standing and is recrystallized from etherhexane to give analytically pure methyl o-[N-(1-carbamoyl-1,2-dimethylpropyl)formimidoyl]benzoate, mp 79°-80.5° C.

1. temperatureis heated
2. filtrationThe mixture is filtered
3. concentrationconcentrated in vacuo
4. customThe residue crystallizes on standing
5. customis recrystallized from etherhexane