Trifluoroacetic anhydride → Tert-butyl 2-cyano-4,4-difluoropiperidine-1-carboxylate

Participants

Reaction Steps

To a solution of tert-butyl 2-carbamoyl-4,4-difluoro-piperidine-1-carboxylate, 13g, (1.72 g, 6.51 mmol) in CH2Cl2 (50 mL) was added was N,N-triethylamine (2.03 mL, 14.61 mmol) followed by the dropwise addition of (2,2,2-trifluoroacetyl)-2,2,2-trifluoroacetate (1.02 mL, 7.32 mmol). After 15 minutes, the mixture was diluted with aqueous saturated NaHCO3 solution and the layers were separated. The organic phase was washed with water, dried over Na2SO4, filtered and evaporated to dryness. The crude residue was passed through a plug of silica gel and eluted with 10-30% EtOAc/hexanes to afford the desired product, 13h.

Provenance & Evidence