Acetic Anhydride → HCID 13809734, compound

Participants

Reaction Conditions

Reaction Steps

To a suspension of benzodiazapine (92.0 g, 0.62 mole) and K2CO3 (90.2 g, 0.65 mole, −325 mesh) in CH3CN (1000 ml) was added acetic anhydride (63.4 g, 58.6 ml, 0.62 mole) in 0.5 h (reaction mixture was cooled in ice water to maintain the reaction mixture temperature between 15-22° C.). The suspension was stirred for 0.5 h at room temperature (check TLC after 30 min, eluent ethyl acetate:MeOH 9:1). The reaction mixture was evaporated and to the residue water (400 ml) was added. The suspension was cooled in ice, filtered, washed with cold water (50 ml×2). Dried under vacuum to give 109.7 g of 4-acetylbenzodiazepine as a white solid, yield 93%).

Provenance & Evidence