A New Route to 2,5-Diamino-4,6-dichloropyrimidine, A Key Precursor of 9-Substituted Guanines
17 September 2002 (online)
An improved synthesis of 2,5-diamino-4,6-dihydroxypyrimidine (7) is reported. The direct chlorination of 7 provides the shortest (2 step) synthesis of 2,5-diamino-4,6-dichloropyrimidine (5) reported to date. The procedure described here affords an easy approach to 5, a key intermediate to various 9-substituted guanines.