1,4-Dibromobutane → 1-(Pyridin-2-yl)cyclopentanecarbonitrile

Beteiligte Stoffe

Reaktionsschritte

To a suspension of sodium hydride (60%) (0.745 g, 18.644 mmol) in dimethyl sulfoxide (10 mL) was dropwise added a mixture of pyridin-2-yl-acetonitrile (429) (1 g, 8.475 mmol) and 1,4-dibromo-butane (1.831 g, 8.475 mmol) dissolved in dimethyl sulfoxide-ether (10 mL, 1:1) at 0° C. and the reaction mixture was stirred for 30 min at the same temperature and then stirred at room temperature for 4 h. After completion of the reaction (monitored by silica TLC, Rf=0.4, in 10% ethyl acetate/hexane) the mixture was quenched with HCl (1N, 10 mL). The reaction mixture was diluted water (20 mL) and extracted with ethyl acetate (2×50 mL) combined extracts were washed with water (20 mL) and brine (2×20 mL). The organic phase was thereafter dried and concentrated in vacuo to get a crude mass which was purified by combi-flash to get 1-pyridin-2-yl-cyclopentanecarbonitrile (430) (1.2 g, 82%) as a color less liquid.

Herkunft & Nachweise