Hydrochloric Acid → HCID 22176339, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of ethyl 4-butoxy-2-cyclopropylmethyl-6-fluoro-1-oxo-1,2-dihydro-3-isoquinolinecarboxylate (9.03 g, 25 mmol) in tetrahydrofuran (30 mL) and ethanol (30 mL) was added sodium hydroxide (3.00 g, 75 mmol). The obtained mixture was refluxed under heating for 12 h. The reaction mixture was poured into water, acidified with 1N hydrochloric acid and extracted with ethyl acetate. The extract was washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was dissolved in benzyl alcohol (20 mL) and the obtained solution was added dropwise to a solution of sodium hydride (5.0 g, 125 mmol)(60% in oil) in benzyl alcohol (20 mL). The obtained mixture was stirred at 150° C. for 12 h. The reaction mixture was poured into 1N hydrochloric acid and extracted with ethyl acetate. The extract was washed with brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The obtained crystals were recrystallized from tetrahydrofuran-diisopropyl ether to give 6-benzyloxy-4-butoxy-2-cyclopropylmethyl-1-oxo-1,2-dihydro-3-isoquinolinecarboxylic acid (7.31 g, 69.4%) as crystals.

Provenance & Evidence