(Z)-tert-butyl (1-(5-bromo-2-fluorophenyl)-2,2-difluoroethylidene)carbamate → [1-(5-Bromo-2-fluoro-phenyl)-1-difluoromethyl-but-3-enyl]-carbamic acid tert-butyl ester

Participants

Reaction Steps

To a solution of [1-(5-bromo-2-fluoro-phenyl)-2,2-difluoro-eth-(Z)-ylidene]-carbamic acid tert-butyl ester (9.61 g, 27.3 mmol) in 114 ml THF at −75° was added dropwise allylmagnesium chloride solution 2 mol/L in THF (15.0 ml, 30 mmol). The reaction temperature was not allowed to exceed −60° C. After 10 minutes the reaction was quenched with 10% aqueous NH4Cl and extracted with TBME. The organic phase was washed with brine, dried with Na2SO4 and evaporated. The crude product was chromatographed on silica gel with 1-5% TBME/hexane to give 10.39 g of the title compound.

Provenance & Evidence