Direct Synthesis of 6-Arylpurines by Reaction of 6-Chloropurines with Activated Aromatics

Highly functionalized C6-aryl-substituted purine analogues were synthesized through direct arylation of 6-chloropurine with aromatics promoted by anhydrous AlCl3 in a single step. The reactions, which were conducted using a 3-fold excess of AlCl3 in refluxing 1,2-dichloroethane, gave moderate to excellent product yields in 0.5 h. This work is complementary to the classical coupling reactions for the synthesis of C6-aryl-substituted purine analogues.