反应详情

A slurry of L-cyclohexylalanine (2.44 g, 14.3 mmol) and powdered NaOH (1.14 g, 28.6 mmol) in DMSO (20 mL) was heated to 100° C. for 20 min until the mixture viscosity decreased and stirring was enabled. 2-Chlorobenzoxazole (1.99 g, 13.0 mmol) was added, and the solution was stirred at 100° C. for 4 h. Upon cooling to room temperature, the solution was poured into 1 M HCl. The precipitate was filtered and dried to afford 2-(S)-(benzooxazol-2-ylamino)-3-cyclohexyl propionic acid was isolated as a white powder (1.69 g, 41%).

1. stirringthe solution was stirred at 100° C. for 4 h
2. filtrationThe precipitate was filtered
3. customdried