Potassium Carbonate → 3,4-Dihydro-5-hydroxy-6-methoxy-1(2H)-isoquinolinone

Participants

Reaction Steps

Into a 50-mL 3-necked round-bottom flask, was placed ethyl 6-methoxy-1-oxo-1,2,3,4-tetrahydroisoquinolin-5-yl carbonate (1.5 g, 5.65 mmol, 1.00 equiv), methanol (20 mL) and K2CO3 (2.34 g, 16.81 mmol, 3.00 equiv). The resulting solution was stirred for 3 h at room temperature. The solids were filtered out. The resulting mixture was concentrated under vacuum. The residue was applied onto a silica gel column with ethyl acetate (100%). This resulted in 0.7 g (64%) of 5-hydroxy-6-methoxy-1,2,3,4-tetrahydroisoquinolin-1-one as a off-white solid. 1H NMR (300 MHz, DMSO-d6) δ: 2.83 (m, 2H), 3.78 (s, 3H), 4.14 (s, 2H), 6.63-6.66 (2s, 1H), 6.88-6.91 (2s, 1H); MS (ESI) m/z 194 ([M+H]+).

Provenance & Evidence