Hydrochloric Acid → 1-(5-Bromo-3-chloropyridin-2-yl)cyclopropane-1-carbonitrile

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

1.38 g of sodium hydroxide was dissolved in 40 ml of water and 0.93 g of benzyltriethylammonium chloride was added at ambient temperature. A solution of 1.00 g of (5-bromo-3-chloro-pyridin-2-yl)-acetonitrile (step 1) in 1.31 g of 1-bromo-2-chloroethane was then added dropwise. Then the reaction mixture was stirred at 60° C. for 2.5 hours. Subsequently, the reaction mixture was cooled to 0° C. and 36% aqueous hydrochloric acid was added in order to obtain pH=1 (about 10 ml). The reaction mixture was extracted with two 50m I portions of ethyl acetate. The organic phase was washed with brine, dried over sodium sulfate, filtered and concentrated. 1.16 g of crude material was obtained as a pale brown sticky solid. The crude material was stirred in diethyl ether and the orange suspension was filtered. The filtrate was concentrated to give 910 mg of 1-(5-bromo-3-chloro-pyridin-2-yl)-cyclopropanecarbonitrile as an orange oil. 1H-NMR (CDCl3): 8.96 ppm (s, 1H), 7.92 ppm (s, 1H), 1.75 ppm (m, 2H), 1.60 ppm (m, 2H).

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