N-bromobutanimide → (S)-tert-butyl (1-((9-bromo-6-methyl-5-oxo-5,6-dihydrobenzo[c][2,7]naphthyridin-8-yl)oxy)-4-methylpentan-2-yl)carbamate

Participants

Reaction Conditions

Reaction Steps

To a solution of (S)-tert-butyl (4-methyl-1-((6-methyl-5-oxo-5,6-dihydrobenzo[c][2,7]naphthyridin-8-yl)oxy)pentan-2-yl)carbamate (0.100 g, 0.235 mmol) (as prepared in Ex. 2, Part D) in anhydrous acetonitrile (5 mL) was added N-bromosuccinimide (0.042 g, 0.235 mmol) and the mixture was heated at 85° C. for 5 h. The reaction mixture was diluted with water (10 mL), extracted with ethyl acetate (2×20 mL). The combined organic layers were dried over sodium sulfate and evaporated under reduced pressure to afford crude product which was purified by preparative TLC (gradient of ethyl acetate and petroleum ether) to afford (S)-tert-butyl (1-((9-bromo-6-methyl-5-oxo-5,6-dihydrobenzo[c][2,7]naphthyridin-8-yl)oxy)-4-methylpentan-2-yl)carbamate (80 mg, 0.159 mmol, 68% yield) as an off-white solid. LC/MS (ESI) m/e 504.2 [(M+H)+, calcd for C24H31BrN3O4 504.1]; LC/MS retention time (method A): tR=2.23 min.

Provenance & Evidence