Two 3D open coordination frameworks constructed by CdII or ZnII perchlorate and 4-(4-pyridyl)-3,5-bis(2-pyridyl)-1,2,4-triazole showing selective anion-exchange behaviors to acetate

Two isostructural 3D coordination polymers (CPs) {[M(L242)2](ClO4)2}n (MII = CdII for 1 and ZnII for 2) have been constructed from metal perchlorates and a tripyridyltriazole ligand 4-(4-pyridyl)-3,5-bis(2-pyridyl)-1,2,4-triazole (L242). The host framework of each CP comprises two interpenetrating lvt topological networks. Three types of 1D channels with different chirality (achirality and left-handed or right-handed helicity) are observed to hold the perchlorate guest anions. Interestingly, both CPs materials have the exclusive and irreversible anion-exchange behaviors for acetate (OAc−), which however, are unavailable to chloride (Cl−), fluoroborate (BF4−), or nitrate (NO3−) anion. CPs 1 and 2 also show ligand-based solid-state fluorescent emissions at room temperature.