Hydrochloric Acid → Ethyl 2-cyclobutylthiazole-4-carboxylate

A solution of HCl (4M in 1,4-dioxane, 3.46 mL) was added to a solution of ethyl 2-(cyclobutanecarboxamido)-3-mercaptopropanoate (example 58, step a) (3.2 g) in ethanol (20 mL) and the resulting mixture stirred overnight. The solvent was evaporated and the residue azeotroped twice with toluene. The residue was redissolved in acetonitrile (50 mL), manganese dioxide (12 g) was added and the mixture heated at reflux overnight. The reaction was filtered through a pad of Celite which was then washed with MeCN (3×100 mL). The combined filtrate and washings were evaporated and the residue was purified by silica gel chromatography eluting with 9:1 isohexane:ethyl acetate. The fractions containing product were combined and evaporated to give the subtitled compound as a clear oil. Yield 0.48 g.

1. customThe solvent was evaporated
2. customthe residue azeotroped twice with toluene
3. dissolutionThe residue was redissolved in acetonitrile (50 mL)
4. additionmanganese dioxide (12 g) was added
5. temperaturethe mixture heated
6. temperatureat reflux overnight
7. filtrationThe reaction was filtered through a pad of Celite which
8. washwas then washed with MeCN (3×100 mL)
9. customThe combined filtrate and washings were evaporated
10. customthe residue was purified by silica gel chromatography
11. washeluting with 9:1 isohexane
12. additionThe fractions containing product
13. customevaporated

ORDレコード

ord-f5c2feef18584ad1bd8bf0b26215d5ba

出典データセット

uspto-grants-2014_01

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08629271B2