Yield:-

Reaction Conditions:

with dmap in 1,4-dioxane at 75; for 0.5 h;

Steps:

61
2-Amino-5-bromothiazole-4-carbonitrile (1.20 g, 5.88 mmol) was dissolved in 50 mL of dioxane. Di-tert-butyl dicarbonate (2.56 g, 11.76 mmol) and N,N-dimethylpyridin-4-amine (35.9 mg, 0.295 mmol) were added to the reaction mixture. The reaction was complete after heating at 75° C. for 30 minutes. The solvent was evaporated under reduced pressure. Saturated sodium bicarbonate was added into the reaction mixture, and the mixture was extracted with EtOAc (2×100 mL). The organic layers were combined, washed with brine, and dried over sodium sulfate. The crude product was purified by column chromatography (condition: 15% EtOAc in hexane). LCMS (API-ES) m/z (%): 303.9 (100%, M⁺).

References:

AMGEN INC. US2007/173506, 2007, A1 Location in patent:Page/Page column 53; 53-54