1-(5-Bromo-2-pyridinyl)-4-ethylpiperazine synthesis

Yield:364794-57-0 98%

Reaction Conditions:

with potassium carbonate in dimethyl sulfoxide at 120; for 2 h;Microwave irradiation;

Steps:

1-(5-Bromopyridin-2-yI)-4-ethylpiperazine (B52 .1)

A mixture of 5-bromo-2- fluoropyridine (500 mg, 2.84 mmol), 1-ethylpiperazine (487 mg, 4.26 mmol), and K2C03(668 mg, 4.83 mmol) in DMSO (7 mL) was heated in microwave at 120 °C for2 h. Satd. aq. NaHCO3 solution was added, and the mixture was extracted with EtOAc, dried, concentrateed, and purified by flash chromatography to afford the title compound (756 mg, 98% yield) as a pale yellow syrup. 1H NMR (CDCI3, 400M Hz) O (ppm): 8.21 (5, 1H), 7.54 (dd, 1H), 7.28 (5, 1H), 6.57 (d, 1H), 3.56 (5, 4H), 2.57 (5, 4H), 2.49 (dd, 2H), 1.16 (t,3H); LCMS: [MH] 271.9.

References:

WO2017/221100,2017,A1 Location in patent:Paragraph 0277