The　electrochemical　synthesis　of　5-purin-6＇-ylthiocatechols　was　carried　out　by　anodic　oxidation　of　catechol　derivatives　1a-1d　in　the　presence　of　6-mercaptopurine　(2)　in　aqueous　solution.　Results　of　cyclic　voltammetry　and　controlled-potential　electrolysis　indicated　that　the　starting　catechols　were　first　oxidized　to　the　corresponding　o-benzoquinone,　which　underwent　further　Michael　addition　with　6-mercaptopurine　to　produce　titled　products　3a-3d　following　an　EC　(E=electrochemical　and　C=chemical　step)　mechanism.　Such　work　further　demonstrates　the　versatility　of　the　anodic　oxidation　of　catechols　and　their　in-situ　transformation　for　the　synthesis　of　derivatized　catechols.