Piperazine → 1-(Pyridin-3-yl)piperazine

Temperature

120 °C

3-Bromopyridine (1.0 g, 6.32 mmol) and piperazine (3.2 g, 37.9 mmol) were dissolved in xylene (10 mL) and the solution was purged with argon for 10 min. Potassium tert-butoxide (0.99 g, 8.86 mmol) and catalytic Pd(PtBu3)2 (320 mg, 0.63 mmol) were added and the reaction mixture was heated to 120° C. for 10 h, cooled to room temperature, diluted with EtOAc and filtered through Celite. The filtrate was washed with water and brine, dried over anhydrous Na2SO4, and concentrated under reduced pressure. The crude product was purified by column chromatography (silica 60-120 mesh, eluent 10% MeOH in CH2Cl2) to get 1-(pyridin-3-yl)piperazine (350 mg, yield 35%). 1H NMR (400 MHz, DMSO-d6) δ 8.26 (d, J=3.0 Hz, 1H), 7.97-7.95 (dd, J=4.6 Hz, 1.1 Hz, 1H), 7.29-7.26 (m, 1H), 7.20-7.16 (m, 1H), 3.08-3.06 (m, 4H), 2.83-2.81 (m, 4H). MS (ESI) m/z: Calculated for C9H13N3: 163.11. found: 164.0 (M+H)+

1. customthe solution was purged with argon for 10 min
2. temperaturecooled to room temperature
3. filtrationfiltered through Celite
4. washThe filtrate was washed with water and brine
5. dry with materialdried over anhydrous Na2SO4
6. concentrationconcentrated under reduced pressure
7. customThe crude product was purified by column chromatography (silica 60-120 mesh, eluent 10% MeOH in CH2Cl2)

ORD record

ord-f397252be3ca4b80abd14c1aa08fe8b9

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08981084B2