Acetic Anhydride → HCID 15299309, compound

Participants

Reaction Steps

A suspension of 1.0 g (3.1 mmol) of 5-(4-nitrophenyl)-8-methyl-9H-7H-1,3-dioxolo[4,5-h][2,3]-benzodiazepine is heated in 10 ml of acetic anhydride for 7 hours to 130°-140° C. The solution is poured on ice, and the precipitate is suctioned off. 0.99 g (87% of theory) of a yellow powder is obtained. After combining the corresponding fractions and concentration by evaporation, flash chromatography of this crude product on silica gel 60 with benzene/ethyl acetate (4:1) as a mobile solvent yields 0.78 g (70% of theory) of 7-acetyl-5-(4-nitrophenyl)-8-methyl-7H-1,3-dioxolo[4,5-h][2,3]-benzodiazepine as a solid with a melting point of 200°-202° C. A sample is recrystallized from ethanol and then has a melting point of 205°-207° C. (minor decomposition).

Provenance & Evidence