Selectfluor → Tert-butyl 3-fluoro-4-oxopiperidine-1-carboxylate

Participants

Reaction Steps

To a solution of 4-oxo-piperidine-1-carboxylic acid tert-butyl ester (2.5 g, 12.55 mmol) in anhydrous DMF (5 mL) were added chlorotrimethylsilane (1.95 mL, 15.37 mmol) and triethylamine (4.18 mL, 30.0 mmol). The resulting milky mixture was heated at 80° C. for 17 h, then cooled to RT. The reaction mixture was diluted with water and extracted with EtOAc. The organic layer was separated, dried (MgSO4) and concentrated in vacuo. The resultant residue was purified by column chromatography to give 4-trimethylsilanyloxy-3,6-dihydro-2H-pyridine-1-carboxylic acid tert-butyl ester as a pale yellow oil (1.86 g, 55%). To a solution of 4-trimethylsilanyloxy-3,6-dihydro-2H-pyridine-1-carboxylic acid tert-butyl ester (1.86 g, 6.852 mmol) in acetonitrile (80 mL) was added Selectfluor™ (2.7 g, 7.622 mmol) and the mixture was stirred at RT for 2 h. The resulting solution was diluted with water and extracted with EtOAc. The organic layer was separated, dried (MgSO4) and concentrated in vacuo. The resultant residue was purified by column chromatography to give the title compound as a colourless oil (1.13 g, 76%).

Provenance & Evidence