Acetonitrile → HCID 178432738, compound

Participants

Reaction Conditions

Reaction Steps

A 1 L, three-neck, round-bottom flask equipped with an overhead stirrer, a reflux condenser, an N2 inlet tube, and a temperature probe was charged with 5-(3-(dimethylamino)propyl)-2-methylpyridin-3-amine hydrochloride (25 g, 0.109 mol). Acetonitrile (275 mL, 11 vol) was added to it followed by acetic acid (25 mL, 1 vol). The initial suspension turned into a clear solution after the addition of acetic acid. Chloroformamidine hydrochloride (15.6 g, 0.136 mol, 1.25 equiv) was added to the solution resulting in a suspension. The reaction was heated at 40° C. for 30 min and at 50° C. for another 30 min. Then the temperature was raised to 60° C. and the reaction was continued at this temperature. After 1-2 h at 60° C., the reaction mixture became turbid and after 3-4 h, solid started separating out. The reaction was continued at 60° C. for 20 h and was judged complete by LC-MS analysis. The reaction was cooled to ambient temperature and the solid was collected by filtration (N2 flow was used during the filtration). The filter cake was washed with acetonitrile (50 mL, 2 vol). The solid was dried under high vacuum overnight to obtain N-{5-[3-(Dimethylamino)propyl]-2-methylpyridin-3-yl}guanidine trihydrochloride (32.1 g, 85% recovery) as a light brown solid. Elemental analysis Calcd: C, 41.81; H, 7.02; Cl, 30.85; N, 20.32. Found: C, 41.09; H, 6.72; Cl, 31.51; N, 20.47; 1H NMR (500 MHz, D2O) δ ppm: 8.57 (s, 1H), 8.45 (s, 1H), 3.22-3.19 (m, 2H), 2.90 (t, 2H, J=10 Hz), 2.86 (s, 6H), 2.69 (s, 3H), 2.15-2.07 (m, 2H); ESI-MS m/z 236 (M+H, 100%).

Provenance & Evidence