Hydrochloric Acid → HCID 66611400, compound

Participants

Reaction Steps

A solution of 350 mg (1.3 mmol) 4-methyl-1-oxo-7-(trifluoromethyl)-1H-isochromene-3-carboxylic acid in EtOH (15 ml) was cooled to 0° C. and treated dropwise with a solution of 1.1 ml (12.9 mmol) n-propylamine in EtOH (2 ml) at this temperature. The RS was then stirred at RT for 2 h followed by concentration in vacuo. The residue obtained was diluted with water and acidified with 2M hydrochloric acid to pH˜2 while cooling (ice-water-bath). Afterwards the RS was extracted with a MeOH/EtOAc mixture (1:9 v/v, 100 ml). The organic layer was washed with water (30 ml) and brine (20 ml), dried over Na2SO4 and concentrated in vacuo. This residue obtained was diluted with EtOH (15 ml) and 1 ml conc. sulfuric acid was added slowly at 0° C. The RS was the heated at 80° C. for 2 h. After cooling to RT, the RS was concentrated in vacuo. The residue obtained was diluted with water and extracted with a MeOH/EtOAc mixture (1:9 v/v, 100 ml). The organic layer was washed with water (30 ml) and brine (20 ml), dried over Na2SO4 and concentrated in vacuo to give 360 mg (1.1 mmo, 89%) 4-methyl-1-oxo-2-propyl-7-(trifluoromethyl)-1,2-dihydroisoquinoline-3-carboxylic acid, which was used in the next step without further purification.

Provenance & Evidence