Self-assembly of a M4L6 complex with unexpected S4 symmetry

Abstract

Using 1,4-diaminobenzene and 2-formylpyridine as simple building blocks results in a 1D ligand (rod, L2) to 2D (M₄L₄ grid, C1) to 3D (S₄ symmetrical M₄L₆, C2) complexes upon sequential addition of Cu(I) and Fe(II) ions. The complex C2 can be seen as the smallest possible pseudo-tetrahedron with S₄ symmetry.