反应详情

To a solution of tert-butyl 4-thiocarbamoylpiperidine-1-carboxylate (1 g, 4.09 mmol) in acetone (5 mL) was added 2-chloroacetaldehyde (0.32 g, 4.08 mmol). The mixture was heated under reflux for 4 hours. Additional 2-chloroacetaldehyde (0.32 g, 4.08 mmol) was added and heating was continued for another 14 hours. The solvent was removed by evaporation and the crude product was purified by silica gel chromatography to give tert-butyl 4-(thiazol-2-yl)piperidine-1-carboxylate as an oil [530 mg (1.97 mmol); LC-MS=213.1 (M+H); 1H NMR (300 MHz, CDCl3) 7.74 (d, J=3.3 Hz, 1H), 7.26 (d, J=3.3 Hz, 1H), 4.23 (brd, 2H), 3.22 (m, 1H), 2.91 (t, 2H), 2.14 (m, 2H), 1.77 (m, 2H), 1.48 (s, 9H)].

1. temperatureThe mixture was heated
2. temperatureunder reflux for 4 hours
3. temperatureheating
4. customThe solvent was removed by evaporation
5. customthe crude product was purified by silica gel chromatography