Ammonium formate → HCID 72556533, compound

To a solution of 40 (1.0 g, 2.2 mmol) and ammonium formate (8.32 g, 132 mmol) in 25 mL glacial acetic acid was added 5% Pd/C (1.0 g). The mixture was refluxed for 7.5 h, cooled to room temperature and filtered over Celite. The mixture was concentrated in vacuum then added to 200 mL water. The product was filtered and washed with hexanes. The solid was recrystallized out of toluene, cooled to room temperature and sonicated until the solid was observed. The mixture was then stirred at room temperature for 16 h. The precipitate was collected and washed with hexanes to yield a white solid (0.609 g, 59.1%). 1H NMR (400 MHz, DMSO-d6) δ 12.65 (s, 1H), 12.05 (br s, 1H), 7.72 (s, 1H), 7.30 (d, J=8.8 Hz, 2H), 7.16 (d, J=8.4 Hz, 2H), 7.05 (d, J=8.4 Hz, 2H), 7.01 (d, J=8.4 Hz, 2H), 6.99 (d, J=9.2 Hz, 2H), 6.98 (d, J=8.0 Hz, 2H), 4.92 (dd, J=4.4 and 9.6 Hz, 1H), 3.38 (dd, J=4.4 and 14.0 Hz, 1H), 3.21 (dd, J=9.2 and 14.0 Hz, 1H), 2.24 (s, H).