Imidazole → 1H-Imidazole, 1-[[2-(2,4-difluorophenyl)-3-methyloxiranyl]methyl]-, (2R-cis)-

To a N,N-dimethylformamide (35 ml) solution containing (2R,3R)-3-(2,4-difluorophenyl)-3,4-epoxy-2-butyl methanesulfonate (3.5 g) and imidazole (1.2 g) was added 60% sodium hydride in mineral oil (0.70 g) at 0° C. with constant stirring. After 10 minutes, the temperature was adjusted to 20° C. and the mixture was stirred for 20 hours. The reaction mixture was then poured into water (100 ml) and extracted with ethyl acetate (30 ml×4). The ethyl acetate layers were combined, washed with saturated aqueous sodium chloride solution (30 ml), dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel chromatography (3 cm×15 cm) using methanol-ethyl acetate (5:95) as the eluent. The desired fraction was concentrated under reduced pressure and the residue was crystallized by addition of isopropyl ether and n-hexane to give (2R,3S)-2-(2,4-difluorophenyl)-2-(1-imidazolyl)methyl-3-methyloxirane (1.7 g) as colorless prisms. m.p. 73°-76° C.

1. customwas adjusted to 20° C.
2. extractionextracted with ethyl acetate (30 ml×4)
3. washwashed with saturated aqueous sodium chloride solution (30 ml)
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. customThe residue was purified by silica gel chromatography (3 cm×15 cm)
7. concentrationThe desired fraction was concentrated under reduced pressure
8. customthe residue was crystallized by addition of isopropyl ether and n-hexane

ORD record

ord-3a4583ff419f47ed8d92e53d214e3617

Source dataset

uspto-grants-1995_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05405861