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 starting material is prepared as follows: The mixture of 170 mg of phosphorous 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