反应详情

温度

110 °C

A suspension of thiazole-2-carbohydrazide (4.2 mmol), ethyl 2-amino-2-thioxoacetate (1 equiv) and ammonium chloride (6 equiv) in ethanol (150 mL) was placed in a sealed tube and this was warmed to 110° C. and stirred at that temperature for 11 days. The reaction solution was cooled to rt and conc. Brine was added and the mixture was adjusted to pH-6 and extracted with EtOAc. The organic phases were dried over Na2SO4, filtered and conc. The crude product was purified using SiO2 chromatography and an appropriate solvent gradient (CH3CN/MeOH/CH2Cl2) to give ethyl 3-(thiazol-2-yl)-1H-1,2,4-triazole-5-carboxylate as an off-white solid (Intermediate-2, 37% yield).

1. customwas placed in a sealed tube
2. temperatureThe reaction solution was cooled to rt
3. extractionextracted with EtOAc
4. dry with materialThe organic phases were dried over Na2SO4
5. filtrationfiltered
6. customconc. The crude product was purified