Cu2(OTf)2-Catalyzed and Microwave-Controlled Preparation of Tetrazoles from Nitriles and Organic Azides under Mild, Safe Conditions

摘要

In connection with a project aimed at preparing new series of diketotetrazoles (see compound 1 in Scheme 1, for which two representative tautomers are shown) and pharmacophor-related quinolinocarbonyltetrazoles, as further candidates for HIV-1 integrase inhibitors, we sought a rapid entry into the synthesis of tetrazole esters 2 and/or 5-acetyltetrazoles 3 (Scheme 1). Formation of tetrazole rings by cycloaddition between nitriles and organic azides is in principle the most direct method, but it usually requires very harsh conditions.