Triethylamine → {4-[(2R,3R)-3-{[2-(1,3-benzodioxol-5-yl)-2-oxoethyl]thio}-1-(4-chlorophenyl)-4-oxoazetidin-2-yl]phenoxy}acetic acid

Participants

Reaction Steps

tert-Butyl (4-{(2R,3R)-1-(4-chlorophenyl)-3-[(3-nitropyridin-2-yl)dithio]-4-oxoazetidin-2-yl}phenoxy)acetate (Method 27) (0.70 g, 1.22 mmol) was dissolved in acetone (30 mL) at room temperature, then water (10 mL) and triphenyl phosphine (0.32 g, 1.22 mmol) was added. The mixture was stirred at room temperature for 15 minutes and then concentrated under reduced pressure to afford the crude thiol as a brown oil. This crude thiol was immediately dissolved in CH2Cl2 (30 mL) and 1-benzo[1,3]dioxol-5-yl-2-bromo-ethanone (0.59 g, 2.44 mmol) was added, followed by Et3N (0.34 mL, 2.44 mmol). The mixture was stirred at room temperature for 18 hours, concentrated under reduced pressure and purified by flash-chromatography (Heptane:EtOAc 7:3 and then 2:1). The resulting product (0.90 g) was dissolved in 15 ml formic acid and stirred at room temperature for 3 hours. Concentration under reduced pressure and purification by flash-chromatography afforded the title compound.

Provenance & Evidence