2-Methyl-2-butene → 6-Benzyloxy-7-methoxy-1-(3-methoxy-benzoyl)-isoquinoline-4-carboxylic acid

Participants

Reaction Steps

To a stirred solution of 6-benzyloxy-7-methoxy-1-(3-methoxy-benzoyl)-isoquinoline-4-carbaldehyde (55 mg, 0.13 mmol) in t-butanol (2 mL) and water (2 mL) solution was added sodium dihydrogenphosphate monohydrate (71.1 mg, 0.52 mmol), 2-methyl-2-butene (0.087 mL, 0.77 mmol) and sodium chlorite (69.9 mg, 0.77 mmol) at room temperature. The reaction suspension was then stirred at room temperature for 14 hrs. The resulting two-phase mixture was partitioned between dichloromethane and water and acidified to pH=3 by addition of acetic acid. The aqueous phase was then extracted with dichloromethane (3×20 mL). The combined extracts were washed with saturated aqueous sodium chloride solution (30 mL), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo to afford a brown semi-solid oil. The crude product was recrystallized in methanol to afford 6-Benzyloxy-7-methoxy-1-(3-methoxy-benzoyl)-isoquinoline-4-carboxylic acid (35 mg, 62% yield) as a light yellow solid. HR-MS m/e calcd for C26H21N1O6 (M−H+) 444.1442, found 444.1442; 1H NMR (300 MHz) compatible.

Provenance & Evidence