8-(1) revealed a unique catalytic performance in the selective oxidation of organic compounds with aqueous hydrogen peroxide. The selectivity of alkene oxidation strongly depends on the amount of acidic protons in the cationic part of 1, which can be controlled by pH of precipitation of the TBA salt. Selectivities of almost 100 % were achieved for cyclohexene epoxidation by using TBA 5.5 Na 1.5 K 0.5 H 0.5 -1. In the presence of TBA 5.5 K 0.5 H 2 -1, cyclohexene epoxide readily transformed into trans-1,2-cyclohexanediol, 2-hydroxycyclohexanone, and C-C bond-cleavage products. No allylic oxidation products were found. Vicinal diols yielded α-hydroxyketones and (di)carboxylic acids. Ketonization of cyclohexanol proceeded with selectivity as high as 98 %, whereas 1-hexanol produced hexanal and hexanoic acid. The oxidation products are consistent with a heterolytic mechanism of H 2 O 2 activation. The stability of 1 under turnover condi-