反应详情

To a solution of 6-bromo-4-butoxy-2-cyclopropylmethyl-1-oxo-1,2-dihydro-3-isoquinolinecarboxylic acid (6.31 g, 16 mmol) in tetrahydrofuran (50 mL were added oxalyl chloride (1.7 mL, 19.2 mmol) and N,N-dimethylformamide (2 drops), and the mixture was stirred at room temperature for 1 h. The reaction mixture was concentrated under reduced pressure and the residue was dissolved in tetrahydrofuran (20 mL). The obtained solution was added dropwise to a suspension of sodium tetrahydroborate (2.11 g, 56 mmol) in 1,2-dimethoxyethane (30 mL) at 0° C. The obtained mixture was stirred at 0° C. for 1 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 ethyl acetate-diisopropyl ether to give 6-bromo-4-butoxy-2-cyclopropylmethyl-3-hydroxymethyl-1(2H)-isoquinolinone (5.87 g, 96.5%) as crystals.

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. dissolutionthe residue was dissolved in tetrahydrofuran (20 mL)
3. stirringThe obtained mixture was stirred at 0° C. for 1 h
4. extractionextracted with ethyl acetate
5. washThe extract was washed with brine
6. dry with materialdried over anhydrous magnesium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe obtained crystals were recrystallized from ethyl acetate-diisopropyl ether