4-Toluenesulfonyl chloride → 1-Tosylpiperidin-4-one

Participants

Reaction Steps

To a solution of 4-piperidone monohydrate hydrochloride (7.68 g, 50 mmol) in methylene chloride (50 ml) were added sequentially p-toluenesulfonyl chloride (10.50 g, 55.07 mmol) and triethylamine (21 ml). The mixture was stirred at room temperature for 16 h before being quenched with water (100 ml). The organic layer was washed with 1 M HCl (100 ml) and brine (100 ml), and dried over sodium sulfate. Evaporation of the solvent gave the desired ketone (8.60 g, 68%) as a colorless solid. mp 130-132° C.; 1H NMR (500 MHz, CDCl3) δ2.40 (s, 3H), 2.58 (t, J=6.4 Hz, 4H), 3.38 (t, J=6.4 Hz, 4H), 7.35 (d, J=7.8 Hz, 2H), 7.68 (d, J=8.3 Hz, 2H).

Provenance & Evidence