Methyl iodide → 4-[(2S,3S,4S)-2-ethyl-3-hydroxy-4-methyl-5-oxopyrrolidin-1-yl]-2-(trifluoromethyl)benzonitrile

To a solution of diisopropylamine (0.603 mL) in tetrahydrofuran (8 mL) was added dropwise n-butyllithium-hexane solution (2.56 mL, 1.6 mol/L) at −78° C., the mixture was stirred for 1 hr, and a solution of 4-[(2S,3S)-2-ethyl-3-hydroxy-5-oxopyrrolidin-1-yl]-2-(trifluoromethyl)benzonitrile (490 mg) in tetrahydrofuran (6 mL) was added dropwise. The mixture was stirred at −78° C. for 30 min, iodomethane (0.510 mL) was added dropwise at −78° C., and the mixture was stirred at 0° C. for 1 hr. Aqueous ammonium chloride solution was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: hexane/ethyl acetate=30/1→1/4) and further purified by basic silica gel chromatography (eluent: hexane/ethyl acetate=30/1→1/4) to give the title compound as a colorless solid (yield: 66.5 mg, 13%).

1. stirringThe mixture was stirred at −78° C. for 30 min
2. stirringthe mixture was stirred at 0° C. for 1 hr
3. extractionthe mixture was extracted with ethyl acetate
4. dry with materialThe extract was dried over anhydrous magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. customThe residue was purified by silica gel column chromatography (eluent: hexane/ethyl acetate=30/1→1/4)
7. customfurther purified by basic silica gel chromatography (eluent: hexane/ethyl acetate=30/1→1/4)

ORD record

ord-73a67e6e3a33429fae754f6d75b0ca80

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08420694B2