Diisopropylamine → (R)-2-[2-(3-Chloro-phenyl)-2-oxo-ethyl]-pyrrolidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

Diisopropylamine (764 uL, 5.4 mmol) was dissolved in THF (15 mL) under nitrogen and cooled to −70° C. Then a 1.6 M solution of butyllithium in hexane (3.4 mL, 5.4 mmol) was added and stirring at −70° C. was continued for 15 min. Then a solution of (3-chloro-phenyl)-trimethylsilanyloxy-acetonitrile (1.18 g, 4.9 mmol) in THF (5 mL) was added and stirring at −70° C. was continued for 30 min, producing a yellow color. Then a solution of (S)-2-iodomethyl-pyrrolidine-1-carboxylic acid tert-butyl ester (1.53 g, 4.9 mmol) in THF (5 mL) was added and stirring at −70° C. was continued for 5 h and then allowed to warm up to 20° C. and stirred overnight. The mixture was extracted with AcOEt, 1 M citric acid, and 50% NaCl. The crude product was purified by flash chromatography on silica gel with a heptane/AcOEt gradient 0-15%. One obtained 500 mg (31%) of a yellow oil. MS: m/z=224 [M+].

Provenance & Evidence