Supramolecular Synthons: Will Giant Rigid Superspheres Do?

[Image: see text] For the first time, the concept of supramolecular synthons was applied to giant rigid superspheres based on pentaphosphaferrocene [Cp(R)Fe(η(5)-P(5))] (R = Me, Et) and Cu(I) halides, which reach 2.1–3.0 nm in diameter. Two supramolecular synthons, σ–π and π–π, are discovered based on halogen···Cp(R) and Cp*···Cp* specific interactions, respectively. The geometry of the synthons is reproducible in a series of crystal structures of various supramolecules. The σ–π synthon alone is realized more frequently for Br-containing superspheres. A combination of the σ–π and π–π synthons is more typical for Cl-containing supramolecules. Each supramolecule can bear up to nine synthons to give mostly 2D and 3D architectures.