反应详情

Added 15 g of {3-[((S)-tetrahydro-furan-3-yloxycarbonylamino)-methyl]-phenyl}-carbamic acid phenyl ester 2e and 8.58 g of 3-methoxy-4-(oxazol-5-yl)benzenamine 2g into a 500 ml 3-necked flask and then purged the system with nitrogen before adding 225 ml of ethyl acetate. Next added 5.43 g of diisopropylethylamine over 1 minute, then heated at reflux for 24 hours. Once the reaction was complete, the mixture was cooled to room temperature and stirred for an additional 1 hour. Precipitated solid was filtered, washed with 45 ml of EtOAc 2 times, then dried at 58° C. for 18 hours (until a LOD is achieved of less than 1%) to give 17.46 g of crude (S)-tetrahydrofuran-3-yl 3-(3-(3-methoxy-4-(oxazol-5-yl)phenyl)ureido)benzylcarbamate 2h (90.4% yield, 98.46% a/a) as a white crystalline solid.

1. custompurged the system with nitrogen
2. additionbefore adding 225 ml of ethyl acetate
3. additionNext added 5.43 g of diisopropylethylamine over 1 minute
4. temperatureheated
5. temperatureat reflux for 24 hours
6. customPrecipitated solid
7. filtrationwas filtered
8. washwashed with 45 ml of EtOAc 2 times
9. customdried at 58° C. for 18 hours (until a LOD