Ammonium Chloride → 1-Boc-4-Methylenepiperidine

Participants

Reaction Conditions

Reaction Steps

In a heated apparatus flushed with protecting gas, methyltriphenylphosphonium bromide (53.82 g, 150 mmol) was suspended in diethyl ether (300 ml) and cooled to 0° C. Potassium tert-butylate (15.78 g, 140 mmol) was added in portions, and the suspension was stirred for 30 min. Boc-4-piperidone (20 g, 100 mmol), dissolved in diethyl ether (200 ml), was slowly added dropwise, and then the mixture was heated to room temperature and stirred for 15 h. The reaction mixture was cooled, and ammonium chloride solution (300 ml, 10%) was added. After phase separation, the aqueous phase was extracted with ether (3×200 ml), and the combined organic phases were dried (MgSO4) and concentrated under vacuum. The crude product was purified by column chromatography (silica gel) with ether/hexane (1:1). Yield: 18.57 g (93%)

Provenance & Evidence