Water → Carbamic acid, N-[(1S)-1-[[(9-bromo-5-oxo-5H-[1]benzopyrano[3,4-c]pyridin-8-yl)oxy]methyl]-3-methylbutyl]-, 1,1-dimethylethyl ester

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of (S)-tert-butyl (4-methyl-1-((5-oxo-5H-chromeno[3,4-c]pyridin-8-yl)oxy)pentan-2-yl)carbamate (0.100 g, 0.242 mmol) (prepared as described in Example 11, Part E) in anhydrous acetonitrile (2 mL) was added NBS (0.043 g, 0.242 mmol) and the mixture heated to 80° C. for 12 h. After completion of reaction, water (10 mL) was added and extracted with ethyl acetate (2×20 mL). The combined organic extracts were dried over sodium sulfate and concentrated under reduced pressure to afford crude compound which was purified by preparative TLC to afford (S)-tert-butyl (1-((9-bromo-5-oxo-5H-chromeno[3,4-c]pyridin-8-yl)oxy)-4-methylpentan-2-yl)carbamate (80 mg, 0.163 mmol, 67% yield) as a pale yellow solid. LCMS (ESI) m/e 491.2 [(M+H)+, calcd for C23H28BrN2O5491.1] LC/MS retention time (method F): tR=1.12 min.

Provenance & Evidence