C-Functionalization of pyrrolo [3, 2-d] pyrimidine scaffold in positions 2, 4, and 7 using cross- coupling reactions was performed. Thus, 2-(5-(benzyloxymethyl)-2, 4-dichloro-5H-pyrrolo [3, 2-d] pyrimidin-7-yl) ethanol, a versatile synthetic precursor for 9-deazapurines and 4, 6- diazaindoles, was prepared by vinylation of the corresponding iodide followed by hydroboration of the double bond. A synthesis of 9-(1, 2-dihydroxyethyl)-9-deazaadenine, ...