3-METHYL-1-[5-(TRIFLUOROMETHYL)PYRIDIN-2-YL]PIPERAZINE synthesis

Yield:866785-24-2 96%

Reaction Conditions:

with triethylamine in toluene at 150; for 20 h;

Steps:

19.1

A solution of 2-chloro-5-trifluoromethylpyridine (2.34 g, 12.9 mmol, 1.0 equiv.), 2-methypiperazine (2.59 g, 25.8 mmol, 2.0 equiv.) and triethylamine (5.4 mL, 38.7 mmol, 3.0 equiv.) in toluene (20 mL) was sealed in a 50 mL of high pressure reaction tube. The reaction mixture was heated to 150° C. with stirring. After stirring at 150° C. for 20 hours, the reaction mixture was cooled to room temperature and then diluted with CH₂Cl₂ (200 mL). The organic mixture was washed with water (100 mL×2), brine and then dried over Na₂SO₄. After filtration and removal of solvent, 3.05 g (96% yield) of the desired intermediate was obtained as a bright yellow solid, which was used without purification. ¹H NMR (400 MHz, CDCl₃), δ (ppm): 8.42 (m, 1H), 7.65 (dd, 1H), 6.66 (d, 1H), 4.26 (m, 2H), 3.14 (m, 1H), 2.94 (m, 3H), 2.60 (dd, 1H), 1. 18 (d, 3H).

References:

US2005/234046,2005,A1 Location in patent:Page/Page column 51