Ammonium Chloride → tert-Butyl 2-[4-(5-chloro-2-cyanophenyl)-5-methoxy-2-oxopyridin-1(2H)-yl]-3-hydroxy-3-(tetrahydrofuran-3-yl)propanoate

Participants

Reaction Conditions

Reaction Steps

At −70° C., 6.94 ml (6.94 mmol, 1.3 eq.) of bis(trimethylsilyl)lithium amide (1M in THF) were added dropwise to a solution of 2.00 g (5.34 mmol) of tert-butyl [4-(5-chloro-2-cyanophenyl)-5-methoxy-2-oxopyridin-1(2H)-yl]acetate in 50 ml of tetrahydrofuran, the mixture was stirred at −70° C. for 10 min, a solution of 801 mg (8.00 mmol, 1.5 eq.) of tetrahydrofuran-3-carbaldehyde in 4 ml of tetrahydrofuran was added and the mixture was stirred at −70° C. for 90 min. The reaction mixture was warmed to −20° C., and 25 ml of semisaturated aqueous ammonium chloride solution were added. After phase separation, the aqueous phase was extracted with diethyl ether. The combined organic phases were washed with saturated aqueous sodium chloride solution, dried (sodium sulphate), filtered, concentrated under reduced pressure and dried. The crude product was purified by flash chromatography (KP-SIL, petroleum ether/ethyl acetate 33-75%). Yield: 1.49 g (56% of theory)

Provenance & Evidence