Assembly of strongly phosphorescent hetero-bimetallic and -trimetallic catenane structures based on a coinage metal alkynyl system†
Homo-metallic metal alkynyl complexes exhibit interesting catenane structures, but their hetero-metallic catenane counterparts are under-developed. In this work, we report rare examples of bimetallic Au–Cu (DtbpCC− ligand; Dtbp = 3,5-di-tert-butylphenyl), Au–Ag (tBuCC− ligand), and Au–Cu, Au–Ag (C6-FluoCC− ligand; C6-Fluo = 9,9-dihexyl-9H-fluoren-2-yl) complexes as well as a trimetallic Au–Ag–Cu (C6-FluoCC− ligand) complex, which feature catenane structures. The formation of the catenane structure is significantly affected by the coinage metal ion(s) and change of the structure of the alkynyl ligand. These hetero-metallic catenane structures are strongly luminescent with tunable emission λmax from 503 to 595 nm and Φ values up to 0.83.