反应详情

A solution of 3-(ethoxycarbonyl)piperidinium hydrochloride (10 g, 65 mmol) in acetone was treated with 1-bromo-2-chloroethane (14.7 g, 0.1 mol) and anhydrous potassium carbonate (13.8 g, 0.1 mol) and the mixture stirred at room temperature for 24 h, the mixture was concentrated and the reside was treated with water and extracted with ether. The extracts were combined and concentrated and the crude was purified by chromatography (silica gel, ethyl acetate:petroleum ether 1:5) to give ethyl 1-(2-chloroethyl)piperidine-3-carboxylate. (3.73 g, Y: 26%). 1HNMR (400 MHz, CDCl3); δ: 1.25 (t, J=7 Hz, 3H), 1.40-3.10 (m, 11H), 3.58 (t, J=7 Hz, 2H), 4.15 (q, 2H). LC-MS (ESI) (m/z): 220 (M+1)+.

1. concentrationthe mixture was concentrated
2. additionthe reside was treated with water
3. extractionextracted with ether
4. concentrationconcentrated
5. customthe crude was purified by chromatography (silica gel, ethyl acetate:petroleum ether 1:5)