Isopropanol → HCID 178459484, compound

Participants

Reaction Steps

A solution of 7-chloro-3-(ethoxycarbonyl)pyrazolo[3,4-c][1]benzazepine-4,10(1H,9H)-dione (500 mg, 1.56 mmol), 2-propanol (60 mL), and concentrated hydrochloric acid (3 drops) was subjected to three cycles of partial solvent removal by slow distillation (over 6 hours) followed by overnight reflux. After the third cycle, solvent was removed by rotary evaporation and the crude product was purified by flash chromatography eluting with dichloromethane:2-propanol (95:5-85:15) to yield the title compound as a white solid (256 mg, 48%, m.p. 291° C). Alternatively, the title compound can be prepared as described in Example 18 shown hereinbelow in Table 1.

Provenance & Evidence