Reaction Steps
A 25-mL round bottom flask was charged with N1-(2-(3-chlorophenyl)-6,7-dihydro-5H-cyclopenta[b]pyridin-4-yl)-N4-methylbenzene-1,4-diamine (0.100 g, 0.28 mmol) in tetrahydrofuran (1 mL). To this stirred solution at rt was added acetic acid (0.33 mL, 5.72 mmol) and sodium cyanate (0.186 g, 2.86 mmol). After 16 h, the reaction mixture was diluted with water (20 mL) and saturated sodium bicarbonate was added until pH˜8, at which time, a solid formed. The resultant solid was isolated by filtration, and was purified by chromatography on silica using dichloromethane/methanol (10:0 to 19:1) as eluent to afford 1-(4-((2-(3-chlorophenyl)-6,7-dihydro-5H-cyclopenta[b]pyridin-4-yl)amino)phenyl)-1-methylurea (0.090 g, 80%) as a white solid. MW=392.88. 1H NMR (DMSO-d6, 500 MHz) δ 8.18 (s, 1H), 7.95 (t, J=2.0 Hz, 1H), 7.80 (dt, J=7.5, 1.5 Hz, 1H), 7.46-7.39 (m, 2H), 7.31 (s, 1H), 7.25 (s, 4H), 5.73 (s, 2H), 2.92 (t, J=7.5 Hz, 2H), 3.13 (s, 3H), 2.85 (t, J=7.5 Hz, 2H), 2.09 (quin, J=7.5 Hz, 2H). MS: ESI+, m/z 393 [M+H]+. Treatment with 1.25M HCl in methanol (0.15 mL, 0.19 mmol) afforded the title compound (0.048 g, 90%) as a light yellow solid. MW=429.34. M.p. 154-157° C. decomp. 1H NMR (DMSO-d6, 500 MHz) δ 13.93 (br s, 1H), 9.19 (br s, 1H), 7.92-7.89 (m, 1H), 7.76-7.71 (m, 1H), 7.60-7.52 (m, 2H), 7.33 (s, 4H), 7.18 (s, 1H), 5.87 (s, 2H), 3.16 (s, 3H), 3.07 (t, J=7.0 Hz, 2H), 2.90 (t, J=7.5 Hz, 2H), 2.19 (quin, J=7.5 Hz, 2H); ESI MS m/z 393 [M+H]+.
