2-Chloro-6-fluorotoluene → 3-Bromo-2-chloro-6-fluorotoluene

Participants

Reaction Steps

2-chloro-6-fluorotoluene (5.00 g, 34.6 mmol) and iron (0.1 g, 0.17 mmol) was stirred in a 100 mL flask. Bromine (6.08 g, 38.1 mmol) was added slowly in 3 portions with 1 min between each addition. The reaction was stirred for additional 15 min. Then dichloromethane (50 ml) was added, the reaction mixture transferred to a separation funnel and washed with a sodium thiosulphate solution (10%, 30 mL) until it had turned colorless. The layers were separated and the organic layer was washed with sat. sodium hydrogen carbonate (30 mL), dried and evaporated to give the title compound as a colorless oil (7.57 g, 98%) containing 15% 3-bromo-5-chloro-2-fluorotoluene (calc. by 1H-NMR). The compound was used in the next step without further purification.

Provenance & Evidence