4-Methylthiazole → 2-Acetyl-4-methylthiazole

Temperature

-78 °C

To a solution of n-butyllithium (2.5M in hexane, 14.4 mL) maintained under nitrogen at −78° C. was added a solution of 4-methyl-1,3-thiazole (3 g, 30.26 mmol) in ether (20 mL). The reaction mixture was stirred at −78° C. for 20 min. N-Methoxy-N-methylacetamide (3.4 g, 32.97 mmol) was then added dropwise to the reaction mixture over 10 min. The resulting solution was stirred at −78° C. for 2 hr and then quenched by the addition of aqueous sodium bicarbonate (20 mL). The resulting solution was extracted with ether (3×50 mL). The combined organic layers were dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified on a silica gel column with ethyl acetate/petroleum ether (1/5) to give 2.1 g (39%) of 1-(4-methyl-1,3-thiazol-2-yl)ethan-1-one as a yellow oil: 1H NMR (300 MHz, CDCl3) delta 7.25 (s, 1H), 2.71 (s, 3H), 2.51 (s, 3H).

1. stirringThe resulting solution was stirred at −78° C. for 2 hr
2. customquenched by the addition of aqueous sodium bicarbonate (20 mL)
3. extractionThe resulting solution was extracted with ether (3×50 mL)
4. dry with materialThe combined organic layers were dried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe residue was purified on a silica gel column with ethyl acetate/petroleum ether (1/5)

ORD record

ord-0c8e201dfa6c42859699befca13a6d87

Source dataset

uspto-grants-2014_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08901313B2