Acetyl chloride → 1-[3-(4-Fluoro-phenyl)-5-methyl-3H-[1,2,3]triazol-4-yl]-ethanone

Participants

Reaction Conditions

Reaction Steps

To a suspension of 1-(4-fluoro-phenyl)-4-methyl-1H-[1,2,3]triazole (4.0 g, 23 mmol) in DME (114 mL) was added n-BuLi (1.6 M in hexane, 17.0 mL, 27 mmol) dropwise at −75° C. The mixture was allowed to warm up to −35° C. and was stirred at −35° C. for 1 h. The reaction mixture was cooled again to −78° C. and a light green suspension of CuCN (2.03 g, 23 mmol) and LiCl (1.92 g, 45 mmol) in THF (32 ml) was added rapidly while stirring at −78° C. After 1 h the mixture was allowed to warm up to −35° C. and acetyl chloride (8.02 mL, 113 mmol) was added dropwise at this temperature. Then the reaction mixture was stirred at room temperature for 2 h and then poured carefully into aqueous saturated sodium carbonate solution (160 mL) and extracted with ethyl acetate. The combined organic extracts were washed with brine, dried over sodium sulphate, filtered and evaporated. Purification by chromatography (silica, dichloromethane) afforded the title compound (3.63 g, 69%) as an off white solid. MS: m/e=220.3 [M+H]+.

Provenance & Evidence