Tetrahydrofuran → 3-(2-Bromo-acetyl)-6-fluoro-2-methyl-benzonitrile

Participants

Reaction Conditions

Reaction Steps

Degassed tributyl(1-ethoxyvinyl)tin (200 mL, 591 mmol) was added to a stirred, room temperature mixture of 3-bromo-6-fluoro-2-methyl-benzonitrile (115 g, 537 mmol) and cis-PdCl2(PPh3)2(18.9 g, 26.9 mmol) in degassed dioxane (1149 mL) and the mixture was stirred at 100° C. for 22 hours. Completion of the reaction could be seen by plating of palladium metal onto the side of the flask. The reaction was cooled to 0° C. and THF (575 mL) and Water (230 mL) were added followed by NBS (110 g, 618 mmol) (added portionwise over 15 min, maintaining internal temperature <5° C.). After 30 minutes, HPLC showed full consumption of the intermediate enol ether. The solution was diluted with MTBE (1000 mL) and washed with 0.5% aqueous HBr (3×500 mL), then washed with water. The organics were dried over MgSO4, filtered and concentrated. A precipitate was generated, and the solid was filtered and washed several times with hexanes. It was dried by nitrogen sweep, providing 3-(2-Bromo-acetyl)-6-fluoro-2-methyl-benzonitrile.

Provenance & Evidence