Hydrochloric Acid → 1,7,8,9-Tetrahydro-pyrano[2,3-g]indazol-8-ol

Participants

Reaction Steps

To a solution of the product of Step E (1.44 g, 4.75 mmol) in methanol (100 mL) was added saturated aqueous potassium carbonate (10 mL) and the mixture stirred for 18 h at ambient temperature. Water (200 mL) was added to the reaction mixture and the pH adjusted to 7 with conc HCl followed by extraction ethyl acetate (5×100 mL). The combined extracts were dried (MgSO4) and evaporated to tan solid (0.84 g, 93%): 1H NMR (DMSO-d6) δ 12.77 (s, 1H), 7.94 (s, 1H), 7.49 (d, J=6.0 Hz, 1H), 6.66 (d, J=6.0 Hz, 1H), 5.02 (t, J=6.0 Hz, 1H), 4.85-4.95 (m, 1H), 3.62 (m, 2H), 2.9-3.4 (m, 2H); LC/MS (+APCI) m/z 191 (M+H).

Provenance & Evidence