Pentane → Ethyl 2-((tert-butoxycarbonyl)amino)-1,3-thiazole-4-carboxylate

Temperature

50 °C

Ethyl 2-aminothiazole-4-carboxylate (10.0 g, 58.1 mmol) was taken up in 150 mL of anhydrous THF along with di-tert-butyl carbonate (Boc2O, 12.67 g, 58.1 mmol) along with 10 mg of 4-(dimethyl)aminopyridine (DMAP). The reaction mixture was stirred at 50° C. for 4 h and then at room temperature for 18 h. It was then concentrated under reduced pressure to obtain a thick oil. Pentane was added and the resulting crystalline materials were collected by filtration and dried to afford 10.5 g of ethyl 2-(tert-butoxycarbonylamino)thiazole-4-carboxylate. This material (10.5 g, 38.5 mmol) was dissolved in 300 mL of anhydrous THF and cooled in Dry Ice-acetonitrile bath. A solution of 1 M Super Hydride™ in THF (85 mL) was then added over a period of 10 min. The resulting reaction mixture was stirred at −45° C. for 2 h. Another portion of 1 M Super Hydride™ in THF (35 mL) was then added and the reaction mixture was stirred for an additional 2 h at −45° C. The reaction was quenched at −45° C. by the addition of 50 mL of brine. Upon warming to room temperature, the reaction mixture was concentrated under reduced pressure. The resulting mixture was extracted with EtOAc. The combined organic layers were washed with brine, dried (Na2SO4) and concentrated under reduced pressure. The resulting residue was purified by chromatography to afford 6.39 g of tert-butyl 4-(hydroxymethyl)thiazol-2-ylcarbamate (72%).

1. waitat room temperature for 18 h
2. concentrationIt was then concentrated under reduced pressure
3. customto obtain a thick oil
4. filtrationthe resulting crystalline materials were collected by filtration
5. customdried

ORD record

ord-09674d482ee8425c919997e3d8fc3ece

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08685970B2