Reaction #1265394

Reaction equation

N-Methoxy-N-methylacetamide

Butyllithium

benzothiazole

→

title compound

Yield 39.0%

1-Benzothiazol-2-yl-ethanone

Yield 39.0%

Solvents

THF

Conditions

Workup

1. 1
   Temperatureto warm to room temperature overnight
2. 2
   OtherThe reaction was quenched by the addition of 1M HCl (10 mL)
3. 3
   Extractionextracted with ethyl acetate (3×15 mL)
4. 4
   DryingThe combined organic extracts were dried over solid MgSO4
5. 5
   Filtrationfiltered
6. 6
   ConcentrationThe filtrate was concentrated under reduced pressure
7. 7
   Otherpurified by column chromatography (10% ethyl acetate in hexanes)

Procedure

Butyllithium (10.2 mL, 16.3 mmol, 1.6 M, 1.1 Eq) was added dropwise to a stirred solution of benzothiazole (1.6 mL, 14.8 mmol, 1.0 Eq) in anhydrous THF (15 mL) at −78° C. under nitrogen. The resultant solution was stirred at −78° C. for one hour. N-Methoxy-N-methylacetamide (1.7 mL, 16.3 mmol, 1.1 Eq) was added in one portion and the reaction stirred at −78° C. for 3 hours. The resultant solution was allowed to warm to room temperature overnight. The reaction was quenched by the addition of 1M HCl (10 mL) and extracted with ethyl acetate (3×15 mL). The combined organic extracts were dried over solid MgSO4 and filtered. The filtrate was concentrated under reduced pressure and purified by column chromatography (10% ethyl acetate in hexanes) to give the title compound as a yellow solid (1.0 g, 39% yield): 1H NMR (400 Mhz, CDCl3) δ 2.85 (3H, s), 7.54-7.62 (2H, m), 8.01 (1H, d), 8.21 (1H, d); MS: ES+ 178.0 (100%).

Source