(2e)-3-{2,6-Difluoro-4-[(isopropoxycarbonyl)amino]phenyl}prop-2-enyl diazoacetate → (Racemic)isopropyl 3,5-difluoro-4-[(1s,5r,6r)-2-oxo-3-oxabicyclo[3.1.0]hex-6-yl]phenylcarbamate

Participants

Reaction Steps

A solution of (2E)-3-{2,6-difluoro-4-[(isopropoxycarbonyl)amino]phenyl}prop-2-enyl diazoacetate (2.4 g, 7.07 mmol) in 170 mL of toluene/dichloromethane (1:2) was added dropwise over 14 h to a refluxing solution of bis-(N-t-butylsalicylaldiminato) copper(II) (0.147 g, 0.35 mmol) in 120 mL of toluene. After the addition was complete, the reaction mixture was heated another hour at reflux, then cooled, filtered and concentrated. The crude oil was purified by column chromatography (15-40% EtOAc-hexanes) to provide the title compound (a racemic mixture) as a yellow solid.

Provenance & Evidence