Ethanol → 3-amino-8-fluorochromane-5-carboxamide

Reaction equation

[F:1][C:2]1[CH:3]=[CH:4][C:5]([C:15]([NH2:17])=[O:16])=[C:6]2[C:11]=1[O:10][CH2:9][CH:8]([N+:12]([O-])=O)[CH2:7]2.C(O)C>O1CCCC1.[Ni]>[NH2:12][CH:8]1[CH2:7][C:6]2=[C:5]([C:15]([NH2:17])=[O:16])[CH:4]=[CH:3][C:2]([F:1])=[C:11]2[O:10][CH2:9]1

Participants

Procedure

8-Fluoro-3-nitro-3,4-dihydro-2H-1-benzopyran-5-carboxamide (9.0 g, 37.5 mmol), dissolved in tetrahydrofuran (100 mL) and absolute ethanol (400 mL), was subjected to atmospheric hydrogenation conditions using Raney nickel (W-2, 9 g) at room temperature. The reaction was complete after 48 hours, at which time the catalyst was filtered off, washed with hot ethanol and the combined solvents were removed in vacuo to give 7.8 g (99% yield) of an off-white solid. A portion was recrystallized from ethyl acetate to give white crystals as the title compound (mp 187-188° C). EIMS (70 eV) m/z (relative intensity) 210 (6, M+), 194 (30), 193 (100), 192 (20), 178 (12).