Synthesis of a redox active analogue of adenine

An analogue of adenine 3, in which the aminopyrimidine moiety is annulated to a cyclopentadienyl ring of ferrocene, was synthesized from ferrocenecarboxaldehyde. The key intermediate in this synthesis was 2-aminoferrocenenitrile, which was prepared regio- and stereoselectively. An X-ray crystallographic structure study of 6, a derivative of 3 obtained by acetylation, confirmed the structure of the product.