反应详情

温度

0 °C

2-(piperidine-1-carbonyl)-cyclohexanone (19) (4.0 g, 19 mmol) was dissolved in diethyl ether (5 mL) and cooled to 0° C. under N2. Bromine (5.9 g, 19 mmol, 1.0 mL) was added dropwise over 15 min and the reaction mixture was allowed to warm to room temperature over 90 min. The solid was collected by filtration to give 5.86 g (quantitative) of 2-bromo-6-(piperidine-1-carbonyl)-cyclohexanone (20) as a white solid which was used in the next step without purification. The structure was confirmed by 13C NMR (75 MHz, DMSO-d6) δC 17.3, 24.2, 25.3, 25.8, 32.5, 44.0, 51.6, 1083, 145.5, 167.8.

1. temperatureto warm to room temperature over 90 min
2. filtrationThe solid was collected by filtration