Ethyl Acetate → 4H-[1,2,4]triazolo[4,3-a][1,5]benzodiazepine

Participants

Reaction Conditions

Reaction Steps

A mixture of 4H-[1,2,4]triazolo[4,3-a][1,5]benzodiazepine,5,6-dihydro-1-methyl-8-bromo-6-(4-chloro-phenyl) (Compound 13; 60 mg, 0.15 mmol), methyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzoate (81 mg, 0.30 mmol), and cesium carbonate (98 mg, 0.30 mmol) in dioxane (2 mL) and water (1 mL) was heated at 120° C. for 20 minutes under microwave (pressure: 17.2 bar, equipment power: 150 W). The solid was filtered and the filtrate was concentrated to give a residue. To the residue, ethyl acetate (30 mL) was added and the mixture was washed with brine (20 mL×3). The organic phase was dried over anhydrous sodium sulfate and then filtered. The filtrate was concentrated to give a residue, which was purified by column chromatography (silica gel, dichloromethane/methanol=10:1) to afford 4H-[1,2,4]Triazolo[4,3-a][1,5]benzodiazepine, 5,6-dihydro-1-methyl-8-(4-carboxy-phenyl)-6-(4-chloro-phenyl) as a white solid (30 mg, 47%).

Provenance & Evidence