Triethylamine → 5,10-dihydro-5-(4-nitrobenzoyl)-4H-pyrazolo-[5,1-c][1,4]benzodiazepine

Participants

Reaction Steps

To a solution of 10 mmol of 5,10-dihydro-4H-pyrazolo[5,1-c][1,4]benzodiazepine in 50 ml of methylene chloride under argon is added 15 mmol of triethylamine followed by ice bath cooling. A solution of 11 mmol of 4-nitrobenzoyl chloride in 10 ml of methylene chloride is added dropwise. Following complete addition, the ice bath is removed and the reaction mixture stirred at room temperature for 2 hours. The volatiles are removed in vacuo to give a residue which is dissolved in ethyl acetate. The solution is washed with water, NaHCO3, and brine. The reaction mixture is dried with Na2SO4, filtered and evaporated in vacuo to give a solid which is purified by flash chromatography on silica gel to give desired product as a solid, m.p. 227°-229° C.

Provenance & Evidence