Tetrahydrofuran → (R)-5-Biphenyl-4-ylmethyl-3-methylene-2-oxo-pyrrolidine-1-carboxylic acid tert-butylester

Participants

Reaction Conditions

Reaction Steps

(R)-5-Biphenyl-4-ylmethyl-3-[1-dimethylaminometh-(E/Z)-ylidene]-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester (7-a, R1=Boc, R6=Me, R7=Me) (7 g) is added to THF (210 ml) and the resulting mixture cooled to −78° C. Diisobutylaluminium hydride (109 ml, 103 mmol; 0.95 M in THF) is added over 1.5 h. To the mixture is then added Rochelle's Salt (430 ml; 1.2 M in water) and the mixture stirred vigorously. Ethyl acetate (400 ml) is added and the phases are separated. The organic phase is concentrated in vacuo. The resulting residue is dissolved in ethyl acetate (20 ml) and washed with brine (20 ml). Phases are separated. The organic phase is then concentrated in vacuo. Diethyl ether (50 ml) is added, filtered and the filtrate concentrated to give (R)-5-biphenyl-4-ylmethyl-3-methylene-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester (4-a, R1=Boc).

Provenance & Evidence