反应详情

2-Methoxyisobutyric acid (0.50 g, 4.23 mmol) was dissolved in MeCN (8.5 mL). 1H-Benzo[d][1,2,3]triazol-1-ol (20% hydrate) (0.65 g, 4.23 mmol) and N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (0.81 g, 4.23 mmol) were added and the mixture was stirred at RT for 2 h. Semicarbazide hydrochloride (0.47 g, 4.23 mmol) was added and the mixture was stirred for an additional 12 h. Organic solvent was removed in vacuo and the residue was suspended in water (85 mL). Potassium hydroxide (0.48 g, 8.5 mmol) was added and the mixture was stirred at RT until complete dissolution of solids. The mixture was then stirred at 100° C. for 12 h and then allowed to cool to RT. The solution was saturated with solid NH4Cl and extracted with EtOAc (8×50 mL). The combined organics were dried (Na2SO4) and concentrated in vacuo to afford 3-(2-methoxypropan-2-yl)-1H-1,2,4-triazol-5(4H)-one (0.35 g, 52.6%) as an amorphous solid. 1H NMR (400 MHz, DMSO-d6): δ 11.44 (s, 1H), 11.28 (s, 1H), 2.96 (s, 3H), 1.36 (s, 6H).

1. stirringthe mixture was stirred for an additional 12 h
2. customOrganic solvent was removed in vacuo
3. stirringthe mixture was stirred at RT until complete dissolution of solids
4. stirringThe mixture was then stirred at 100° C. for 12 h
5. temperatureto cool to RT
6. extractionextracted with EtOAc (8×50 mL)
7. dry with materialThe combined organics were dried (Na2SO4)
8. concentrationconcentrated in vacuo