tert-Butanol → (RS)-4-(5-bromo-2-fluoro-phenyl)-4-methyl-oxazolidin-2-one

Temperature

80 °C

A solution of the crude (RS)-4-bromo-1-fluoro-2-(2-iodo-1-isocyanato-1-methyl-ethyl)-benzene (10.01 g, 26 mmol) in N,N-dimethyl-formamide (90 ml) was treated at room temperature with silver tetrafluoroborate (5.58 g, 29 mmol) and tert-butanol (3.86 g, 52 mmol). The yellow suspension was stirred at 80° C. overnight. For the workup, the reaction mixture was evaporated at reduced pressure, the residue triturated in ethyl acetate then filtered. The solution was concentrated at reduced pressure and the crude product purified by chromatography on silica gel using a gradient of dichloromethane/methanol=100/0 to 40/60 as the eluent. The (RS)-4-(5-bromo-2-fluoro-phenyl)-4-methyl-oxazolidin-2-one was obtained as a white solid (4.33 g, 61% of theory). MS (ISP): m/z=274.2 [M+H]+, 276.2 [M+2+H]+.

1. customFor the workup, the reaction mixture was evaporated at reduced pressure
2. customthe residue triturated in ethyl acetate
3. filtrationthen filtered
4. concentrationThe solution was concentrated at reduced pressure
5. customthe crude product purified by chromatography on silica gel using a gradient of dichloromethane/methanol=100/0 to 40/60 as the eluent

ORD record

ord-b1317c2e54cf40a9835bf7f34f2bce50

Source dataset

uspto-grants-2013_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08399459B2