Azobisisobutyronitrile → 2-[2-(Bromomethyl)-5-fluorophenyl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

Participants

Reaction Steps

3-Fluoro-6-methylphenylboronic acid pinacol ester (29a, 5.01 g, 21.2 mmol) and 140 ml CCl4 were placed in 500 ml round-bottom flask. NBS (3.97 g, 22.3 mmol, 1.05 eq) and AIBN (0.054 g, 0.33 mmol, 0.016 eq) were added and the reaction mixture was refluxed for 3.5 h in the presence of 75 W incandescent bulb. After 3.5 h the solution was cooled down to room temperature allowing the succinimide to precipitate out. The solid was filtered off. The solvent was removed and oily product was collected. Purification with column chromatography (95/5 Hexanes/Ethyl acetate) resulted in pure product (30a, 5.59 g, 84% yield).

Provenance & Evidence