Trifluoromethanesulfonic anhydride → HCID 18675884, compound

Participants

Reaction Conditions

Reaction Steps

1.5 g (0.0103 mol) of 7-hydroxyisoquinoline and 5.3 ml of pyridine are cooled to 0° C. 1.86 ml of triflic anhydride are added thereto dropwise. The mixture is stirred at 0° C. for 1 hour and then at ambient temperature for 2 hours. It is poured into a water/ice mixture and extracted with ethyl acetate, the organic phase is dried and the solvent is evaporated under reduced pressure. The crude product is purified by chromatography on a column of silica gel, elution being carried out with a cyclohexane/ethyl acetate=7/3 mixture. 7-Hydroxyisoquinoline trifluoromethanesulfonate is obtained in the form of an oil. 1.65 g of this product are mixed under argon with 27.5 ml of anhydrous dimethylformamide, 41 mg of palladium acetate, 1.65 ml of anhydrous triethylamine and 1.38 g of N,N-diethylethanolamine vinyl ether. The mixture is heated at 80° C. for 36 hours. It is poured into a water/ethyl acetate mixture, the two phases are separated, the organic phase is washed with water and dried, and the solvent is evaporated under reduced pressure. The residue is purified by chromatography on a column of silica gel, elution being carried out with an ethyl acetate/methanol=9/1 mixture. 2-[2-(7-Isoquinolyl)ethenyl)oxy)]-N,N-diethyl-1-ethanamine is obtained. 1.5 g of this product are treated with 130 ml of water and 13 ml of 96% sulfuric acid. The mixture is heated at 60° C. for 4.5 hours and is poured into ice, a saturated aqueous NaHCO3 solution is added thereto and extraction is carried out with ethyl acetate. The organic phase is dried and the solvent is evaporated under reduced pressure. The title compound is obtained.

Provenance & Evidence