Tetrahydrofuran → 8-Chloro-5,6-dihydro-4-oxo-6-phenyl-4H-pyrazolo[1,5-a][1,4]benzodiazepine-2-carboxaldehyde

Participants

Reaction Steps

A solution of 5.85 g. (17 mmol) of the end product of Example 14 in 600 ml. dry THF was mixed with 24 g. of activated MnO2 and heated to reflux for 17 hours. The mixture was cooled, filtered and the collected solids washed thoroughly with THF. The combined filtrate and washings were concentrated in vacuo. Recrystallization of this crude product from THF/hexane yielded the desired end product. An analytical sample was prepared by an additional recrystallization from THF/hexane and was obtained as colorless plates: mp 276°-278°.

Provenance & Evidence