反应详情

温度

5.5 °C

At room temperature N′-hydroxy-4-[(2-methoxyethyl)amino]-1,2,5-oxadiazole-3-carboximidamide (50.0 g, 0.226 mol) was dissolved in 6.0 M hydrochloric acid aqueous solution (250 mL, 1.5 mol). Sodium chloride (39.5 g, 0.676 mol) was added followed by water (250 mL) and ethyl acetate (250 mL). At 3-5° C. a previously prepared aqueous solution (100 mL) of sodium nitrite (15.0 g, 0.217 mol) was added slowly over 1 hr. The reaction was stirred at 3-8° C. for 2 hours and then room temperature over the weekend. LCMS indicated reaction completed. The reaction solution was extracted with ethyl acetate (2×200 mL). The combined ethyl acetate solution was dried over sodium sulfate and concentrated to give the desired product (49.9 g, 126%) as a crude white solid. LCMS for C6H10ClN4O3 (M+H)+: m/z=221.0. 1H NMR (400 MHz, DMSO-d6): δ 13.43 (s, 1 H), 5.85 (t, J=5.6 Hz, 1 H), 3.50 (t, J=5.6 Hz, 2 H), 3.37 (dd, J=10.8, 5.6 Hz, 2 H), 3.25 (s, 3 H).

1. customroom temperature
2. customreaction
3. extractionThe reaction solution was extracted with ethyl acetate (2×200 mL)
4. dry with materialThe combined ethyl acetate solution was dried over sodium sulfate
5. concentrationconcentrated