Mutual stabilisation between MII4L6 tetrahedra and MIIX42− metallate guests

Abstract

A complex host–guest equilibrium employing metal ions incorporated into both the host and guest is discussed. M^IIX₄²⁻ metallate guests are shown to provide a good size and shape match for encapsulation within the M₄L₆ tetrahedral capsules, facilitating the generation of previously unreported Zn₄L₆ complexes. Displacement of the initial, primary template anion (ZnBr₄²⁻) by a secondary template anion (ClO₄⁻) is shown to result in the formation of a pentagonal-prismatic Zn₁₀L₁₅ structure that incorporates both Br⁻ and ClO₄⁻. Furthermore, the formation of heterometallic complexes provides direct evidence for metal exchange between the guest and host complex.