Trifluoroacetic acid → 7-Methyl-6-(piperidin-4-yloxy)-2h-isoquinolin-1-one

Participants

Reaction Conditions

Reaction Steps

6.4 g (13.4 mmol) 4-[2-(4-methoxy-benzyl)-7-methyl-1-oxo-1,2-dihydro-isoquinolin-6-yloxy]-piperidine-1-carboxylic acid tert-butyl ester were dissolved in 30.5 g (267.4 mmol) trifluoroacetic acid. After 1 h at room temperature the mixture was heated for 2 h in a microwave oven at 150° C. Then the excess trifluoroacetic acid was distilled off in vacuo and the residue was diluted with 130 mL of 1 M hydrochloric acid. The aqueous phase was washed with methylene chloride 3 times and then it was freeze dried to give a hydrochloride, which was crystallized from isopropanol. This furnished 3.2 g 7-methyl-6-(piperidin-4-yloxy)-2H-isoquinolin-1-one (16) as hydrochloride.

Provenance & Evidence