tert-Butyl(2S,3S)-3-hydroxy-2,3-dimethyl-5-oxo-pyrrolidine-1-carboxylate → (4S,5S)-4-hydroxy-4,5-dimethylpyrrolidin-2-one

tert-Butyl (2S,3S)-3-hydroxy-2,3-dimethyl-5-oxo-pyrrolidine-1-carboxylate (1.00 g) was dissolved in hydrogen chloride-ethyl acetate solution (10 mL, 4 mol/L), and the mixture was stirred at room temperature for 14 hr. The reaction solution was concentrated under reduced pressure, and recrystallized from isopropanol/n-hexane to give the title compound (309 mg, 55%) as colorless crystals. Furthermore, the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: ethyl acetate→methanol/ethyl acetate=1/10), and the obtained solid was crystallized from diisopropyl ether to give the title compound (220 mg, 39%) as a white powder.

1. concentrationThe reaction solution was concentrated under reduced pressure
2. customrecrystallized from isopropanol/n-hexane

ORD record

ord-4f17fbd2f9804420a0ea553c3fdff722

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08420694B2