Boron trifluoride → 644982-11-6

Participants

Reaction Conditions

Reaction Steps

A solution of tert-butyl 3-fluoro-4-oxopiperidine-1-carboxylate (20.0 g, 92.1 mmol) in 1:1 (CH2Cl2:Et2O, 250 mL) was cooled to −60° C. using an IPA/dry ice bath. In a separate flask was added BF3-Etherate (12.8 mL, 101 mmol) and Et2O (40 mL) which was cooled to 0° C., then ethyl 2-diazoacetate (12.6 mL, 120 mmol) was added. This mixture was added to the oxopiperidine solution and the reaction mixture was slowly warmed to ambient temperature over 2 hours. Water was added (100 mL) and the mixture was stirred at ambient temperature for 30 minutes. The phases were separated and the aqueous phase was extracted with EtOAc (100 mL) and the combined organic phases were washed with 1N KHSO4, followed by brine and then dried over Na2SO4, filtered and concentrated. This provided the product as a thick, yellow oil (26 g).

Provenance & Evidence