Herein we introduce tetrazole and its suitably designed derivatives as powerful ester- cleaving reagents. By first performing a detailed ab initio computational study, we found that, in the side chain of 5-alkyl-1 H-tetrazoles, introduction of a heteroatom (eg, N, O, or S at the α-position of the tetrazole ring) raises the charge on the tetrazole nucleus significantly. All calculations have been performed using restricted Hartree-Fock (RHF) and hybrid ab initio ...