Hydrochloric Acid → 2-(3,4-Dimethoxyphenyl)-1-(thien-2-yl)ethanone

Participants

Reaction Steps

2-Lithiothiophene (1.0 M in THF, 33.0 mL, 33.0 mmol, Aldrich Chemical Co.) was added dropwise to N-methyl-N-methoxy-(3,4-dimethoxyphenyl)acetamide (5.26 g, 22.0 mmol) in anhydrous THF at -78° C. The reaction was allowed to proceed 90 min., then diluted with 100 mL Et2O and poured into 1 N aq. HCl. The aqueous phase was extracted with Et2O and the combined organic fraction was washed with brine, dried (Na2SO4), and concentrated in vacuo. Flash chromatography (25% EtOAc/hexanes) yielded 2.91 g (50%) 2-(3,4-dimethoxyphenyl)-1-(thien-2-yl)ethanone as a brown oil. MS 263 (M+H)+, 280 (M+NH4)+.

Provenance & Evidence