Synthesis of novel rigid triazine-based calix[6]arenes

In this report, the stepwise synthesis of a novel rigid and functionalised macrocycle 2 based on triazine and phenylenediamine linkers, is presented. Poor recognition of the macrocycle 2 for its substrates is observed, which shows experimentally that for the meltriazine based-calix6]arene system, the binding ability of the melamine moiety gets more benefit from the ring flexibility derived from a xylenediamine linker 1 than from a phenylenediamine linker 2.