Synthesis of (purin-6-yl)acetates and 6-(2-hydroxyethyl)purines via cross-couplings of 6-chloropurines with the Reformatsky reagent

A novel approach to the synthesis of 6-(2-hydroxyethyl)purines was developed based on Pd-catalyzed cross-coupling reactions of 6-chloropurines with the Reformatsky reagent followed by reduction by NaBH4 and treatment with MnO2. This methodology was successfully applied to the syntheses of 6-(ethoxycarbonylmethyl)- and 6-(hydroxyethyl)purine bases and nucleosides.