The application of diaryltelluronium cations as a chalcogen bonding organocatalyst is described.

The cationic polymerization of p-methoxystyrene (pMOS) was briefly investigated using TeOTe-TfO having the dicationic ditelluroxane structure as a chalcogen bonding (ChB) organocatalyst. With the HCl adduct of pMOS (pMOS·HCl) as an initiator, under appropriate conditions, the polymer molecular weight could be roughly controlled by the monomer feed ratio. We have subsequently performed the polymerization using the mononuclear telluronium cation TeMe-TfO as an organocatalyst and various alcohols as an initiator. For example, by using the H2O adduct of pMOS (pMOS·H2O) and under the condition of [pMOS·H2O]/[TeMe-TfO]/[pMOS] = 10:5:500 in mM concentration at 0 °C, poly­(pMOS) with M n = 6930 and M w/M n = 1.47 was obtained. Polymerizations with varying monomer feed ratios, monomer re-addition experiments, the careful analysis of the polymer chain ends by the 1H nuclear magnetic resonance (NMR) spectra, and polymerizations in the presence of water revealed that the cationic polymerization of pMOS proceeds in the living mechanism through the reversible activation of a carbon–hydroxy bond by the ChB interaction. By using the 125Te NMR spectra, it was confirmed that TeMe-TfO can be recovered without decomposition.