Functionalized organotellurium macrocycles: tuning their optical bandgap and investigation of their catalytic activity†

Abstract

This work deals with the synthesis, characterization, and optical properties of 12-membered tellurium macrocycles functionalized with an allyl group. These are synthesized by the reaction of bis-p-methoxyphenyl tellurium dihalide with phenyl allyl phosphinic acid at room temperature. SCXRD reveals that the cationic macrocycle is capped by two halide ions giving an overall composition of [((p-OMePh)₂Te)₂(O)(PhC₃H₅PO₂)(μ₄-X)]₂, where X = Cl (Cl-TAM) and Br (Br-TAM). On reacting Cl-TAM with KI, we were able to isolate the iodo-capped macrocycle [((p-OMePh)₂Te)₂(O)(PhC₃H₅PO₂)(μ₄-I)]₂ (I-TAM). The presence of allyl groups at the periphery would allow these macrocycles to act as potential building blocks. Optical absorption studies show that the bandgap can be tuned by exchanging the capping halides. These systems were also found to act as catalysts for the detoxification of CEES, a mustard gas simulant.