Dimethylformamide → tert-butyl (2R,6S)-2-formyl-6-methylpiperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To 2.50 g(12.5 mmol) of (S)-N-tert-butoxycarbonyl-2-methylpiperidine in 25 ml of dehydrated diethyl ether solution were added 1.89 ml(1 equivalent) of N,N,N′,N′-tetramethylethylenediamine at −60° C. under an atmosphere of argon, and then 13.3 ml(1.1 equivalent) of sec-butyllithium were added dropwise. After the temperature of reaction mixture was raised to −20° C., it was cooled again to −70° C. and 1.46 ml(1.5 equivalents) of N,N-dimethylformamide were added dropwise. After stirring for about 2 hours, 20 ml of saturated solution of ammonium chloride were added to the reaction mixture to stop the reaction. The aqueous layer was separated, which was extracted with ether(10 ml×3). Combined organic layers were dried over anhydrous magnesium sulfate, filtered and solvent was distilled off. The residue was purified by means of silica gel column chromatography(hexane:ethyl acetate=8:1) to obtain 1.58 g of (2R,6S)-tert-butyl 2-formyl-6-methyl-1-piperidinecarboxylate (yield 55%).

Provenance & Evidence