Water → HCID 22750102, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 5-amino-4-carboxy-1-ethoxyisoquinoline (50.8 g) and 2,5-dimethoxytetrahydrofuran (32 cc) in acetic acid (250 cc) is kept at a temperature between 90° and 95° C. for 35 minutes, whilst stirring. The solution is cooled to about 20° C. and then poured into water (1250 cc). The yellow crystals which precipitate are filtered off and washed with water (5 × 50 cc). After drying under reduced pressure (1 mm Hg) at 20° C., crude 4-ethoxy-7-oxo-7H-indolizino[7,6,5-de]isoquinoline (52.7 g) is obtained. After recrystallisation from ethanol, the pure product melts at 188° C.

Provenance & Evidence