Ethyl bromopyruvate → 4-Thiazolecarboxylic acid, 2-propyl-, ethyl ester

Ethyl 3-bromo-2-oxopropanoate (6.32 mL) was added to a solution of butanethioamide (example 87, step a) (5.2 g) in ethanol (100 mL) and the resulting mixture heated at reflux overnight. The solvent was evaporated and the residue partitioned between ethyl acetate (100 mL) and saturated sodium hydrogen carbonate solution (100 mL). The layers were separated and the aqueous phase extracted with ethyl acetate (2×100 mL). The combined organic solutions were washed with brine (100 mL) dried over sodium sulphate, filtered and evaporated. Purification was by silica gel chromatography eluting with 10:1 isohexane:ethyl acetate. The fractions containing product were combined and evaporated to give the subtitled compound as a yellow oil. Yield 5.24 g.

1. temperaturethe resulting mixture heated
2. temperatureat reflux overnight
3. customThe solvent was evaporated
4. customthe residue partitioned between ethyl acetate (100 mL) and saturated sodium hydrogen carbonate solution (100 mL)
5. customThe layers were separated
6. extractionthe aqueous phase extracted with ethyl acetate (2×100 mL)
7. washThe combined organic solutions were washed with brine (100 mL)
8. dry with materialdried over sodium sulphate
9. filtrationfiltered
10. customevaporated
11. customPurification
12. washeluting with 10:1 isohexane
13. additionThe fractions containing product
14. customevaporated

ORD record

ord-897bfe11b5884f7ca1ae0d13d6f6486a

Source dataset

uspto-grants-2014_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08629271B2