Synthesis of meso-2,2’-bipyridyl-substituted calix[4] arenes and their response to metal cations

Abstract

A convenient synthetic approach to meso-substituted with 2,2’-bipyridine and 1-(pyridin-2‑yl)isoquinoline residues calix[4]arenes is reported. This approach involves the reaction of generated in situ 2‑lithio-calix[4]arene with 1,2,4‑triazine precursor with the following aromatization of the obtained adduct, and the aza-Diels- Alder reaction of the 1,2,4‑triazinyl-substituted calix[4]arene with 2,5‑norbornadien or in-situ generated 1,2‑dehydrobenzene. The UV/fluorescence response of thus obtained meso-pyridyl-substituted calix[4]arenes to metal cations is studied.