Hydrochloric Acid → HCID 22176368, compound

6-Chloro-4-methoxy-2-methyl-1-oxo-1,2-dihydro-3-isoquinolinecarboxylic acid (0.67 g, 2.5 mmol) was dissolved in tetrahydrofuran (10 ml) and oxalyl chloride (0.26 ml, 3 mmol) and N,N-dimethylformamide (2 drops) were added thereto. 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 (10 ml). The obtained solution was added dropwise to a suspension of sodium tetrahydroborate (0.33 g, 8.8 mmol) in 1,2-dimethoxyethane (20 ml) at 0° C. The obtained mixture was stirred at 0° C. for 1 h, and 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-chloro-3-hydroxymethyl-4-methoxy-2-methyl-1(2H)-isoquinolinone (0.42 g, 66.7%) as crystals.

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. dissolutionthe residue was dissolved in tetrahydrofuran (10 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

ORD record

ord-0f3d8914d6714672ab97b98ec88f6056

Source dataset

uspto-grants-2006_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07034039B2