1-Methyl-4-piperidone → 4-[2-(1-Hydroxy-1-methylethyl)phenyl]-1-methylpiperidin-4-ol

Participants

Reaction Steps

To a stirred solution of 2-(2-bromophenyl)propan-2-ol (step 1, 6.91 g, 32.1 mmol) in tetrahydrofuran (32 mL) was added dropwise a 1.59 M solution of butyllithium in tetrahydrofuran (46.5 mL, 73.9 mmol) at −78° C. for 20 min and the mixture was stirred for 1 h at the same temperature. To the mixture was added dropwise a solution of 1-methylpiperidin-4-one (5.09 g, 45.0 mmol) in tetrahydrofuran (18 mL) at −78° C. for 10 min. This resulting mixture was slowly warmed up to room temperature and stirred for 18 h at the same temperature. The reaction mixture was quenched by the addition of water, and concentrated to give an orange residue. The crude material was partitioned between diethyl ether and water, and then the organic layer was washed with brine, dried over sodium sulfate, and evaporated. The residue was purified by column chromatography on silica gel (150 g) eluting with hexane/ethyl acetate (5/1), dichloromethane/methanol (10/1), then dichloromethane/methanol/triethylamine (10/1/1) to afford 4.62 g (58%) of the title compound as a slight yellow syrup:

Provenance & Evidence