Hydrochloric Acid → Tert-butyl 4-hydroxy-4-isobutyl-2-methylpiperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

Under an argon atmosphere, in a 50-mL pear-shaped evaporating flask was weighed a solution of lanthanum chloride lithium chloride complex in THF (15.6 mL) and cooled to 0° C. To the solution was added dropwise a solution of isobutylmagnesium chloride in THF (3.5 mL) and stirred at 0° C. for 3 hours. A solution of tert-butyl 2-methyl-4-oxopiperidine-1-carboxylate (1 g) in THF (2.0 mL) was further added dropwise. The reaction solution was stirred at 0° C. for 1 hour, heated to 25° C., poured to hydrochloric acid and extracted with ethyl acetate. The organic layer was washed with water and a saturated sodium chloride solution and dried over anhydrous magnesium sulphate. The filtrate was concentrated and the resulting residue was purified by silica gel chromatography (hexane:ethyl acetate=9:1→3:1) to give the titled compound (450 mg) having the following physical properties.

Provenance & Evidence