Dimethylformamide → 12-formyl-2-methyl-3,4-dioxo-1,3,4,14b-tetrahydro-10H-pyrazino[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepine

Participants

Reaction Steps

The mixture of 170 mg of phosphorus oxychloride and 100 ml of dimethylformamide is stirred at room temperature for 30 minutes, whereupon the solution of 281 mg of 2-methyl-3,4-dioxo-1,3,4,14b-tetrahydro-10H-pyrazino[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepine in 5 ml of methylene chloride is added dropwise. After 30 minutes, the mixture is refluxed for another 30 minutes and cooled to room temperature. It is combined with 1.5 g of sodium acetate in 5 ml of water, stirred for 30 minutes and the organic layer separated. It is washed with water, 5% aqueous sodium bicarbonate, dried, evaporated and the residue triturated with diethyl ether, to yield the 12-formyl-2-methyl-3,4-dioxo-1,3,4,14b-tetrahydro-10H-pyrazino[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepine melting at 300°-302°.

Provenance & Evidence