3,4-Dimethylpyridine → 3-Bromo-4,5-dimethylpyridine

Participants

Reaction Conditions

Reaction Steps

3,4-Dimethylpyridine (20 g, 0.186 mol) was added slowly to ice cold oleum (400 mL) with vigorous stirring. The solution was heated to 155° C. and bromine (12.2 mL, 0.223 mol) was added drop wise very slowly. The reaction mass was heated at 155° C. for 24 h. After cooling to room temperature, the mixture was carefully poured into ice water and basified using 10% aqueous sodium hydroxide solution. The compound was then extracted with ethyl acetate (2×500 mL). The organic solution was dried over sodium sulphate and evaporated to yield oil which was purified by column chromatography (20% ethyl acetate/hexane) to obtain the title compound. 1H NMR (400 MHz, CDCl3) δ 8.49 (s, 1H), 8.22 (s, 1H), 2.36 (s, 3H), 2.30 (s, 3H).

Provenance & Evidence