Urea → Ethyl 2-amino-4-(trifluoromethyl)-1,3-oxazole-5-carboxylate

To a suspension of urea (13.5 g) in DMF (50 mL) was added ethyl 4,4,4-trifluoro-2-chloroacetoacetate (10 mL) and the resulting reaction mixture was heated at 120° C. for 3 days. Then, the reaction mixture was cooled to RT and diluted with H2O (100 mL). Then, the reaction mixture was stirred at 0° C. for 1 h. The resulting precipitate was filtered, washed with H2O and dried in vacuo to yield ethyl 2-amino-4-trifluoromethyloxazole-5-carboxylate (A-1) as a white powder (9.8 g, 74% yield). LCMS (ESI) calcd for [M+1]+ 225.1. found 225.1.

1. customthe resulting reaction mixture
2. temperatureThen, the reaction mixture was cooled to RT
3. filtrationThe resulting precipitate was filtered
4. washwashed with H2O
5. customdried in vacuo

ORD-Eintrag

ord-6e5c2e472c064db1a58c107bd547b752

Quelldatensatz

uspto-grants-2014_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08716312B2