Hydrochloric Acid → HCID 86673035, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 7-bromo-2-isoquinolin-3-yl-chromen-4-one O-tert-butyl oxime (120 mg, 0.28 mmol), trans-dichlorobis(triphenylphosphine)palladium (19 mg, 0.028 mmol), copper iodide (10 mg, 0.056 mmol), triphenylphosphine (14 mg, 0.056 mmol) in a mixture of dimethylformamide (3 ml) and acetonitrile (3 ml) was degassed with argon for 10 min and then treated with diethylamine (42 μl, 0.40 mmol) and trimethylsilylacetylene (46 μl, 0.326 mmol). The solution was warmed to 90° C. for 20 hours and then poured onto a 0.5N aqueous solution of hydrogen chloride, extracted with ethyl acetate and purified by flash chromatography over silica gel (gradient cyclohexane/ethyl acetate: 20-50%) to yield 2-isoquinolin-3-yl-7-trimethylsilylethynyl-chromen-4-one O-tert-butyl oxime (63 mg, 50%) as a yellow solid. The solid was dissolved in methanol (10 ml) and treated with potassium carbonate (39 mg, 0.28 mmol) and stirred at room temperature for 18 hours. Methanol was evaporated and the residue was extracted with ethyl acetate washed with water and brine, dried over sodium sulfate and the solution concentrated to dryness to yield 7-ethynyl-2-isoquinolin-3-yl-chromen-4-one O-tert-butyl oxime (49 mg, 89%) as beige solid.

Provenance & Evidence