Hydrochloric Acid → 3-Fluoro-4-(thieno[3,2-b]pyridin-7-yloxy)aniline

Participants

Reaction Conditions

Reaction Steps

To a solution of 3 (660 mg, 2.27 mmol) in MeOH (10 ml) was added conc. HCl (1 ml) and Fe (1.91 g, 34.8 mmol), and the reaction mixture was stirred at 0° C. for 3 hrs, neutralized with aqueous NaHCO3 solution and extracted with EtOAc, producing 3-fluoro-4-(thieno[3,2-b]pyridin-7-yloxy)-phenylamine (4) as a dark oil (500 mg, 83%), which was used directly in the next step. To a solution of the amine 4 (200 mg, 0.69 mmol) in DMF (10 ml) was added 3-oxo-3-(phenylamino)propanoic acid (1, 155 mg, 0.89 mmol), HOBT (121 mg, 0.89 mmol) and EDC (198 mg, 1.035 mmol). The reaction mixture was stirred at room temperature overnight, evaporated to dryness and the residue was dissolved in EtOAc and washed with water. The organic phase was dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by column chromatography (eluent EtOAc:hexane 3:1) to afford the title compound 5a (30 mg, 10% yield) as a white solid (after trituration with Et2O). 1H NMR (400 MHz, DMSO-d6) δ (ppm): 10.5 (s, 1H), 10.2 (s, 1H), 8.49 (d, J=5.48 Hz, 1H), 8.14 (d, J=5.48 Hz, 1H), 7.85 (dd, J=2.35 and 13.01 Hz, 1H), 7.59 (m, 3H), 7.42 (m, 2H), 7.30 (dt, J=1.96 and 7.43 Hz, 2H), 7.05 (t, J=7.24 Hz, 1H), 6.65 (d, J=5.28 Hz, 1H), 3.51 (s, 2H).

Provenance & Evidence