Water → Hydrochloric Acid

Participants

Reaction Steps

Methyl 1,2-Dihydro-2-hydroxy-3-methyl-1-oxo-4-isoquinoline acetate (0.300 g., 1.21 mmol) suspended in 2 ml. ethanol was reacted with potassium tert-butoxide (0.136 g., 1.21 mmol) (Aldrich). The solid dissolved upon warming. After cooling to room temperature 3,4-dichlorobenzylchloride (0.130 ml., 1.21 mmol) (Pfaltz and Bauer) was added and the mixture was stirred overnight. The residue obtained after vacuum evaporation was taken up in ethyl acetate/hexane and filtered. This mother liquor after evaporation in vacuo gave a solid crude ester (256 mg., 52%, mp 90°-94°) which was hydrolyzed for 24 hr in 6.3 ml. of 5:1 dioxane:water containing 1 equivalent of sodium hyroxide. The title compound was obtained upon acidification with 1 N hydrochloric acid and filtration; 215 mg., 45% overall, mp 222° dec.

Provenance & Evidence