反应详情

To a stirred solution of 65 g (40 mmol) 4-methoxy-benzooxazol-2-yl-amine and 4.5 ml (56 mmol) pyridine in 250 ml dichoromethane at 0° C. was added dropwise a solution of 4.1 ml (49 mmol) methyl chloroformate in 50 ml dichoromethane and stirring continued for 3.5 hours. The mixture was then poured onto water and extracted three times with dichloromethane. The combined organic phases were dried over sodium sulfate and concentrated in vacuo. Flash chromatography (dichloromethane) afforded 4.7 g (54%) (4-methoxy-benzooxazol-2-yl)-carbamic acid methyl ester as an off-white crystalline solid. EI-MS m/e (%): 222 (M+, 100), 190 (27), 163 (23).

1. additionThe mixture was then poured onto water
2. extractionextracted three times with dichloromethane
3. dry with materialThe combined organic phases were dried over sodium sulfate
4. concentrationconcentrated in vacuo