Water → Phthalimide

Participants

Reaction Conditions

Reaction Steps

A solution of anthracenylmethyl quininium bromide (200 mg), nitromethane (0.04 ml), potassium carbonate (94 mg) and 2-[[2-bromo-4-[(E)-3-(3,5-dichlorophenyl)-4,4,4-trifluoro-but-2-enoyl]phenyl]methyl]isoindoline-1,3-dione (200 mg) in toluene (2 mL) under argon, was heated for 2 hours at 50° C. then potassium carbonate (64 mg) was added. The reaction was heated for 24 hours at 50° C. then more nitromethane (0.02 mL) was added. The reaction was heated again at 50° C. for 1.5 hours then was allowed to stand at room temperature for 18 hours. Water was then added and the resulting mixture was extracted with dichloromethane and the combined organic fractions were dried over sodium sulfate. The crude product was purified by flash chromatography (0% to 25% ethyl acetate in cyclohexane) to afford 2-[[2-bromo-4-[(3R)-3-(3,5-dichlorophenyl)-4,4,4-trifluoro-3-nitromethyl)butanoyl]phenyl]methyl]isoindoline-1,3-dione (174 mg). Chiral HPLC analysis (Chiralpack IB, Heptane/isopropanol 70/30, flow: 1 mL, retention time 12.10 minutes (major enantiomer), 14.34 minutes (minor enantiomer) indicated that the reaction proceeded with 49% enantioselectivity in favor of the R enantiomer.

Provenance & Evidence