Water → HCID 57219190, compound

Participants

Reaction Conditions

Reaction Steps

Triton B (1.94 mL, 4.3 mmols) was added dropwise to a stirred, cooled (-30° C.) solution of (3S,4R)-3-benzyloxycarbonylamino-4-[2-(2-furyl)ethyl]azetidin-2-one (1.35 g, 4.3 mmols) in N,N-dimethylformamide (15 mL). Stirring was continued for 0.25 hr. at -30° C. The mixture was allowed to warm to 0° C. during about 0.25 hr and then was recooled to -30° C. when a solution of t-butyl bromoacetate (0.764 mL, 4.73 mmols) in DMF (3 mL) was added dropwise. Stirring was continued at -30° C. for 0.25 hr., 1 hr at 0° C. and then for 2 hr at ambient temperatures, when additional t-butyl bromoacetate (0.3 mL) was added. The mixture was stirred for an additional 1 hr and was poured into H2O. The mixture was extracted twice with ethyl acetate. The extracts were washed twice with H2O, followed by saturated NaCl and then dried over MgSO4. The ethyl acetate was removed and the residue flash chromatographed on SiO2 (40 g) with methylene chloride - methanol (98:2) to afford 1.47 g (80% yield) of the title compound as a viscous oil which crystallized. Recrystallization from ethyl acetate-hexanes afforded colorless crystals, mp 82°-84° C.

Provenance & Evidence