Template sol-gel synthesis of mesostructured silica composites using metal complexes bearing amphiphilic side chains: immobilization of a polymeric Pt complex formed by a metallophilic interaction

A bipyridine-based ligand 1 bearing two amphiphilic side chains allowed for the formation of metal complexes Pt(1)Cl-2 (2), [Pt(1)(2)](BF4)(2) (3), and [Pt(1)(2)][Pt(CN)(4)] (4), which are capable of templating the sol-gel synthesis of mesostrucutred silica to give 2-MS, 3-MS and 4-MS, respectively, whose silicate channels are filled with the corresponding platinum complexes. In particular, silica composite 4-MS, upon spin-coating, gives a transparent film, which emits at 619 nm upon excitation at 495 nm, indicating that a weak Pt-Pt bond, formed between Pt(1)(2)(2+) and Pt(CN)(4)(2-) via a metallophilic interaction, is successfully incorporated into the silicate nanochannels.