2-Chlorothiazole → 1-(2-Chlorothiazol-5-yl)ethanone

Temperature

25 °C

A solution of 2-chlorothiazole (5.0 g, 42 mmol) in THF (10 mL) was added dropwise to a −78° C. solution of n-BuLi (2.5 M in hexanes; 18.4 mL, 46 mmol) in THF (140 mL). The solution was stirred for 1 hour, and then N-methoxy-N-methylacetamide (4.7 g, 46 mmol) was added. The mixture was stirred for another hour, and then it was warmed to approximately 25° C. The reaction was quenched by the addition of a saturated aqueous ammonium chloride solution and extracted with ether (3×75 mL). The organics were combined, washed with brine, filtered and then concentrated. The residue was purified by flash chromatography (20 percent ether/pentane on silica gel), yielding 5.9 grams of yellow semi-solid.

1. stirringThe mixture was stirred for another hour
2. customThe reaction was quenched by the addition of a saturated aqueous ammonium chloride solution
3. extractionextracted with ether (3×75 mL)
4. washwashed with brine
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified by flash chromatography (20 percent ether/pentane on silica gel)

ORD record

ord-3ada4b144491483aa99f1add9138521c

Source dataset

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08008487B2