反应详情

N-tert-Butylhydroxylamine hydrochloride (56 g, 0.43 mol, 97%) was dissolved in water (226 g) and charged to a 1 L three-necked glass bottle under argon gas. Ethyl acetate (246 g) and potassium carbonate (79 g, 0.57 mol, 1.3 equiv.) were added and the mixture was stirred vigorously for 1 h at +20 ° C. Both phases were siphoned to a separating funnel. The water phase was separated off and extracted once more with ethyl acetate (100 ml). The organic phases were pooled and acetic acid (28.1 g, 0.47 mol, −1.09 equiv.) was added. The solvent was evaporated off. The resulting clear, yellow-green oil was treated with additional ethyl acetate (203 g) and concentrated again. The bottle was placed in the refrigerator and after 2 h the product had turned crystalline. The substance was easily crushed giving a slightly yellowish powder (63.4 g, 90%). This material could be recrystallised using either toluene or ethyl acetate as solvent. Differential scanning calorimetry showed an endothermic melting point at +67.7° C. Powder X-ray diffraction analysis showed a high degree of crystallinity.

1. customBoth phases were siphoned to a separating funnel
2. customThe water phase was separated off
3. extractionextracted once more with ethyl acetate (100 ml)
4. customThe solvent was evaporated off
5. additionThe resulting clear, yellow-green oil was treated with additional ethyl acetate (203 g)
6. concentrationconcentrated again
7. waitThe bottle was placed in the refrigerator and after 2 h
8. customThe substance was easily crushed