Alkali-metal- and halide-free dinuclear mixed-valent samarium and europium complexes

Abstract

We describe the synthesis of mixed-valent (Ln(ii)/Ln(iii)) dilanthanide complexes supported by a calix[4]pyrrole ligand. The complexes are obtained by one-electron reduction of Ln(iii)/Ln(iii) complexes and are alkali-metal- and halide-free. The complexes are designed to activate small molecules by taking advantage of both the base and the one-electron reductant contained in their structure. We demonstrate a proof-of-principle concept of this mechanism by activating water and silanol.