Synthesis
Step 1: 0.1 g (0.63 mmol) of 2-bromopyridine and 0.065 g (0.75 mmol) of piperazine were placed in a dry 5 mL microwave reactor protected by nitrogen and reacted at 150 °C for 20 min. After completion of the reaction, it was cooled to room temperature. Step 2: The reaction mixture was filtered using diatomaceous earth and the filter cake was washed with ethyl acetate. Step 3: The solvent was removed by distillation under reduced pressure to obtain the crude product. Step 4: Purification of the crude product by silica gel column chromatography with eluent ratio of dichloromethane:methanol=4:1 to obtain 1-(pyridin-2-yl)piperazine in 54% yield.
References
[1] Patent: WO2008/153325, 2008, A1. Location in patent: Page/Page column 43
[2] Patent: WO2006/47415, 2006, A2. Location in patent: Page/Page column 37-38
[3] Journal of the American Chemical Society, 1949, vol. 71, p. 2731,2732
[4] Journal of Organic Chemistry, 1953, vol. 18, p. 1484,1487
[5] Patent: WO2008/62276, 2008, A2. Location in patent: Page/Page column 50
