Sodium borohydride → 2-Chloro-5-(oxiran-2-yl)pyridine

Participants

Reaction Steps

To a stirred solution of the mixture of 2-bromo-1-(6-chloropyridin-3-yl)ethanone and 2-chloro-1-(6-chloropyridin-3-yl)ethanone (5.6 g) in ethanol (100 ml) at 5° C. was added portionwise over 5 min NaBH4 (904 mg). The reaction mixture was then stirred at room temperature for 1 hour to afford a light yellow solution. TLC analysis showed the reaction was complete. Sodium methoxide (645 mg) was then added and the reaction mixture was stirred at room temperature overnight. TLC analysis showed a small amount of starting material remaining and so the reaction mixture was stirred at 50° C. for 1 h. The reaction mixture was then poured into EtOAc and washed with saturated brine. The organic phase was dried over Na2SO4 and concentrated in vacuo to afford (RS)-2-chloro-5-(oxiran-2-yl)pyridine (4.04 g) as a yellow oil which was used in the next step without further purification. MS (ISP): 158.0 ([{37Cl}M+H]+), 156.0 ([{35Cl}M+H]+).

Provenance & Evidence