Acetic Acid → Furo[2,3-c]pyridin-7-amine

Reaction equation

CO[NH:3][C:4]1[N:5]=[CH:6][CH:7]=[C:8]2[CH:12]=[CH:11][O:10][C:9]=12.C(O)(=O)C>C(Cl)Cl.[Zn]>[O:10]1[C:9]2=[C:4]([NH2:3])[N:5]=[CH:6][CH:7]=[C:8]2[CH:12]=[CH:11]1

Participants

Procedure

N-methoxyfuro[2,3-c]pyridin-7-amine (43.0 g, 0.26 mol) in DCM (200 mL) was cooled in a water bath. Zinc dust (36.0 g, 0.64 mol) was added in one portion and stirred for a few min. Acetic acid (18.8 g, 0.31 mol) was added slowly over 5-10 min and stirred for 30 min. The water bath was removed and the mixture was stirred at RT for 16 h. At this point, TLC analysis (5% MeOH in DCM) indicated complete consumption of the starting material. The mixture was diluted with 400 mL of DCM and washed with saturated NaHCO3 until the pH of the wash was about 8.5. The DCM layer was then washed with water (2×100 mL) and then brine. The solution was dried over anhydrous Na2SO4, filtered and concentrated in vacuo. The resulting crude product was purified by flash chromatography (2% MeOH:DCM) to provide 34 g (97%) of the title compound. 1H NMR (300 MHz, CDCl3): δ 4.89 (br s, 2H), 6.71 (d, J=1.8 Hz, 1H), 6.94 (d, J=5.4 Hz, 1H), 7.63 (d, J=1.8 Hz, 1H), 7.84 (d, J=5.4 Hz, 1H).