反应详情

温度

-78 °C

(4E)-4-(methoxymethylidene)-3,4-dihydro-2H-chromene-7-carbonitrile (230 mg, 1.1 mmol) was dissolved in dichloromethane (6 mL). The solution was cooled to −78° C. To above solution was added tribromoborane (1.7 mL, 1 M, 1.7 mmol) dropwise over a course of 5 min and subsequently stirred for 30 min at −78° C. To the reaction mixture was added saturated sodium bicarbonate, extracted with dichloromethane (2×20 mL). The organic phase was washed with brine (5 mL), dried over anhydrous Na2SO4, filtered, concentrated. The crude product was used without purification. 1H NMR (500 MHz, CDCl3, δ in ppm): 7.0-7.4 (3H, aromatic), 6.58 (1H, s), 4.55 (2H, m), 2.98 (2H, m).

1. extractionextracted with dichloromethane (2×20 mL)
2. washThe organic phase was washed with brine (5 mL)
3. dry with materialdried over anhydrous Na2SO4
4. filtrationfiltered
5. concentrationconcentrated
6. customThe crude product was used without purification