Dimethylformamide → 2-Bromo-3-fluoro-5-(trifluoromethyl)pyridine

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-fluoro-5-(trifluoromethyl)pyridin-2-ol (1.0 g, 5.5 mmol, Matrix) and phosphoric tribromide (1.6 g, 5.5 mmol) in N,N-dimethylformamide (2.9 mL, 38 mmol) was heated to 130° C. for 70 minutes. After cooling to room temperature, the mixture was poured onto a mixture of ice and sodium bicarbonate solution (final pH=8). The product was extracted with diethyl ether. The extract was washed with water (twice), followed by brine, dried and solvent removed in vacuo. Flash chromatography, eluting with a gradient from 0-10% ethyl acetate in hexanes afforded product as a colorless oil (0.59 g, 44%). 1H NMR (400 MHz, CDCl3): δ 8.53-8.50 (m, 1H), 7.66 (dd, 1H).

Provenance & Evidence