Diisopropylethylamine → 7-((4-(4-chlorophenyl)-5,6-dihydropyridin-1(2H)-yl)methyl)-4-methyl-3,4-dihydropyrido[2,3-b]pyrazin-2(1H)-one

Participants

Reaction Conditions

Reaction Steps

7-(hydroxymethyl)-4-methyl-3,4-dihydropyrido[2,3-b]pyrazin-2(1H)-one (85.0 mg, 0.44 mmol) was suspended in propionitrile (1 mL) and (cyanomethyl)trimethylphosphonium iodide (123.0 mg, 0.51 mmol) was added followed by N-ethyl-N-isopropylpropan-2-amine (180 ul, 1.03 mmol). To the stirred mixture was then added 4-(4-chlorophenyl)-1,2,3,6-tetrahydropyridine hydrochloride (103.5 mg, 0.45 mmol). The reaction was heated to 90° C. with stirring for 2 h. The reaction was then cooled to room temperature and diluted with water (3 mL) and filtered. The solids were collected and refluxed in ethanol (5 mL) for 1 h. The suspension was cooled back to room temperature and filtered. The precipitate was filtered off and dried in vacuum to afford the title compound (30.2 mg, 19%) as a white solid. 1H NMR (DMSO-d6) δ (ppm): 10.51 (s, 1H), 7.64 (s, 1H), 7.41-7.47 (m, 2H), 7.34-7.40 (m, 2H), 6.97 (d, J=1.8 Hz, 1H), 6.18 (s, 1H), 3.93 (s, 2H), 3.41 (s, 2H), 3.01 (br. s., 2H), 2.91 (s, 3H), 2.60 (br. s., 2H), 2.39-2.47 (m, J=7.3 Hz, 2H). [M+H] calc'd for C20H21ClN4O, 369. found, 369.

Provenance & Evidence