1,1'-Carbonyldiimidazole → HCID 178462853, compound

Participants

Reaction Steps

A mixture of 1.2 g (4.7 mmole) of 4,5-dihydro-5-ethyl-4-oxo-pyrrolo-[1,2-a]-quinoxaline-2-carboxylate acid (prepared by the process of French application No. 2,387,230), 0.81 g (5.0 mmole) of carbonyldiimidazole and 25 ml of anhydrous dimethylformamide was stirred until a clear solution was obtained and 0.425 g (5.0 mmole) of anhydrous 5-amino-tetrazole were added thereto. The mixture was stirred at room temperature for 30 minutes and was then filtered. The recovered product was washed with ethyl acetate and dried over P2O5 under vacuum to obtain 1.4 g of 4,5-dihydro-5-ethyl-4-oxo-N-(1H-tetrazol-5-yl)-pyrrolo-[1,2-a]-quinoxaline-2-carboxamide in the form of white crystals melting at 315°-318° C.

Provenance & Evidence