Coordination-cyclodimeric array containing both channels and cages: photoluminescence recognition of diiodomethane†
Abstract
Self-assembly of a series of ZnX2 (X− = Cl−, Br−, and I−) with 2,3-bis(4′-nicotinamidephenoxy)naphthalene (L) as a new hemi-circular bidentate ligand yields systematic 46-membered metallacyclodimeric species of [ZnX2L]2. These metallacyclodimers constitute, via inter-digitated π⋯π interactions, a characteristically staggered molecular array containing both channels and cages. The slightly different features between the channel and cage have been investigated by 1H NMR and TGA. The crystals with such vacant volumes effectively stabilize the unstable CH2I2 molecule and are monitored by UV spectroscopy. Furthermore, the photoluminescence intensity via the chromophore naphthyl moiety of [ZnCl2L]2 gradually decreases with the addition of CH2I2.