N-bromobutanimide → Methyl 2-(5-bromo-2-methyl-1,3-thiazol-4-yl)-2-(tert-butoxy)acetate

Under a nitrogen atmosphere, N-bromosuccinimide (39 mg, 0.22 mmol) was added to a solution of methyl 2-(tert-butoxy)-2-(2-methyl-1,3-thiazol-4-yl)acetate (15c) (50 mg, 0.21 mmol) in N,N-dimethylformamide (4 mL). The reaction mixture was warmed at 70° C. for 30 minutes then concentrated in vacuo. The residue was diluted with ethyl acetate (40 mL) and washed with water (2×20 mL), brine (20 mL), dried over sodium sulfate, filtered and evaporated under reduced pressure to give the desired product as a yellow oil without further purification (70 mg, 0.21 mmol, 100%).