Potassium ethanethioate → (2S,4S)-4-acetylthio-1-allyloxycarbonyl-2-phthalimidomethylpyrrolidine

Participants

Reaction Conditions

Reaction Steps

A solution of (2S,4R)-1-allyloxycarbonyl-2-phthalimidomethyl-4-methanesulfonyloxypyrrolidine (12.4 g: 30.46 mmole) and 90% potassium thioacetate (5.22 g: 45.69 mmole) in dimethylformamide (130 ml) is heated with stirring at 60° C. for 4 hours. The reaction mixture is diluted with ethyl acetate (200 ml) and ice water (200 ml). The organic layer is taken, successively washed with water (3 times) and saturated brine, dried over magnesium sulfate, and concentrated in vacuo. The residue is purified by silica gel chromatography to give crude (2S,4S)-4-acetylthio-1-allyloxycarbonyl-2-phthalimidomethylpyrrolidine (9.33 g). Yield: 81%. NMR δ(CDCl3) ppm: 1.7 to 1.9(m, 1H), 2.33(s, 3H), 2.4 to 2.7(m, 1H), 3.25 (dd, J=6.8 Hz, J=11.4 Hz, 1H), 3.7 to 4.0(m, 2H), 4.0 to 4.2(m, 2H), 4.3 to 4.6(m, 3H), 5.0 to 5.3(m, 2H), 5.7 to 5.9(m, 1H), 7.7(m, 2H), 7.85(m, 2H).

Provenance & Evidence