A molecular clip throws new light on the complexes formed by a family of cyclam-cored dendrimers with Zn(II) ions. Efficient energy transfer in the heteroleptic complexes.

Complexation of Zn(II) ions by cyclam cored dendrimers appended with four (G0), eight (G1) and 16 naphthyl chromophores (G2) at the periphery have been investigated in CH₃CN-CH₂Cl₂ 1 : 1 (v/v) solution by absorption and emission, ESI-mass and ¹H NMR spectroscopy. The results obtained can be interpreted by the formation of complexes of 2 : 1 dendrimer to metal stoichiometry, at low metal ion concentration, and 1 : 1 complexes upon further addition of Zn(II) ions, for all the dendrimer generations. Upon addition of a molecular clip C²⁻ consisting of two anthracene sidewalls bridged by a benzene group with two sulfate substituents in the para positions, heteroleptic complexes of general formula [GnZnC] are formed.

Metal ion driven formation of a light-harvesting antenna investigated by sensitized luminescence and fluorescence anisotropy.

Zn(ii) complexation drives the formation of a light-harvesting antenna constituted by two multicomponent luminescent ligands: a cyclam-cored dendrimer decorated at the periphery with 16 naphthyl units and an anthracene-based molecular clip.