Boron trifluoride → 1-tert-Butyl 4-ethyl 5-oxoazepane-1,4-dicarboxylate

Participants

Reaction Conditions

Reaction Steps

tert-Butyl-4-oxo-1-piperidinecarboxylate (10 g, 50.19 mmol) was dissolved in Et2O (100 ml) and cooled to −78° C. Ethyl diazoacetate (7.3 ml, 70.26 mmol) and BF3.EtO were sequentially added over 30 min. After stirring at the same temperature for 2 h, the reaction was quenched by careful addition of aqueous potassium bicarbonate, during which the cold bath was removed. After warming up to room temperature, the organic layer was washed with water, dried over Na2SO4 and concentrated. Purification with flash chromatography provided the titled compound (13 g, Yield: 91%). MS (DCI/NH3) m/z 286 (M+H)+.

Provenance & Evidence