5H-Pyrrolo[3,2-d]pyrimidin-4-amine (9CI)

2320-75-4

2227-98-7

Ethyl 4-amino-5-cyano-1H-pyrrole-3-carboxylate (42.62 g, 207 mmol) was added potassium hydroxide (34.1 g, 517 mmol) to its aqueous (500 ml) suspension and the reaction was carried out at reflux for 24 hours. After completion of the reaction, the mixture was cooled to room temperature, concentrated under vacuum and subsequently resuspended in water (100 ml). The resulting suspension was filtered and the brown solid was collected, washed sequentially with water (50 ml) and ether (100 ml), and dried over air to give 9-deazaadenine (18 g, 65% yield) as a brown solid. Melting point >300°C. 1H NMR (500MHz, d6-DMSO) δ 8.12 (s, 1H), 7.51 (brd, J=2.1Hz, 1H), 6.36 (brd, J=2.1Hz, 1H). 13C NMR (125MHz, d6-DMSO) δ 150.4,150.3,147.2,127.8 ,113.6,101.2.