Bromine → 5-Bromo-2,2-difluoro-1,3-benzodioxole

Participants

Reaction Steps

Iron powder (2.8 g, 50 mmol) was added to a solution of 2,2-difluoro-1,3-benzodioxole (15.8 g, 100 mmol) in carbon tetrachloride (200 mL) at 0° C. under a nitrogen atmosphere. Bromine (5.2 mL, 100 mmol) was then added to the mixture dropwise over 15 min. The reaction was heated to reflux for 1 h and then stirred at room temperature overnight. The mixture was filtered through Celite and the filtrate was washed with 0.1N sodium thiosulfate solution. The organic layer was then dried (MgSO4), filtered, and concentrated under reduced pressure to afford the title compound of Step A as an oil (15.2 g, 64%). 1H NMR (CDCl3): δ6.96 (m, 1H), 7.22 (m,2H).

Provenance & Evidence