5H-Pyrrolo[3,4-b]pyridine-5,7(6H)-dione

89-00-9

4664-00-0

General procedure for the synthesis of 2,3-pyridinedicarboximide from 2,3-pyridinedicarboxylic acid: 167 g of 2,3-pyridinedicarboxylic acid (1.0 mol) and 300 mL of concentrated ammonia (28%) were added to a 1000 mL three-necked flask, followed by refluxing and stirring for 6 hours at 140 °C. The reaction was carried out in a liquid mixture of 2,3-pyridinedicarboxylic acid (1.0 mol) and 300 mL of concentrated ammonia (28%). During the reaction, the liquid reaction mixture gradually changed to dark brown color. The progress of the reaction was monitored by thin layer chromatography (TLC) and after confirming the complete reaction of 2,3-pyridinedicarboxylic acid, the reaction mixture was cooled to room temperature. Under continuous stirring, the reaction mixture was slowly poured into 500 mL of cold water, and a large amount of gray solid precipitated immediately. The solid product was collected by filtration and the filter cake was washed with cold water and subsequently dried under vacuum at 60 °C overnight to give 125 g of gray powdery product in 84% yield.