Hydrochloric Acid → 5-(4-morpholinyl)-3-(1-naphthalenylmethyl)-3,4-dihydro-7H-imidazo[4,5-b]pyridin-7-one

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Reaction Steps

A mixture of 5-chloro-7-(methyloxy)-3-(1-naphthalenylmethyl)-3H-imidazo[4,5-b]pyridine (140 mg, 0.432 mmol) and morpholine (2.5 mL, 28.7 mmol) was irradiated in a microwave oven for 4 h at 200° C. The mixture was diluted with water and the pH was adjusted to ca. 7 by the addition of 1 N HCl. The precipitate formed was collected, washed with water and air dried. It was then dissolved in DMSO and purified by RP-HPLC (Gilson, 25-80% AcCN in water plus 0.1% TFA). The fractions containing product were collected, neutralized by the addition of aqueous NaHCO3 sat sol and the volume was reduced to ½-⅓ of the original. The precipitate was collected by filtration, washed with water and dried overnight in a vacuum oven at 45° C. to give 5-(4-morpholinyl)-3-(1-naphthalenylmethyl)-3,4-dihydro-7H-imidazo[4,5-b]pyridin-7-one (45 mg, 0.122 mmol, 28.3% yield). MS (ES+) m/e 361 (MH+); 1H NMR (400 MHz, DMSO-d6) δ ppm 10.83 (br. s., 1H), 8.32-8.47 (m, 1H), 8.00 (s, 1H), 7.94-7.98 (m, 1H), 7.89 (d, J=8.08 Hz, 1H), 7.52-7.61 (m, 2H), 7.47 (dd, J=8.08, 7.07 Hz, 1H), 7.35 (d, J=6.32 Hz, 1H), 6.07 (s, 1H), 5.77 (s, 2H), 3.65-3.75 (m, 4H), 3.35-3.43 (m, 4H)

Provenance & Evidence