Fig. 1

Summary of the self-assembly of the [Pd₂1₄]⁴⁺ cage. A schematic representation of the bifurcation of pathways for the self-assembly of the (NO₃⁻)@[Pd₂1₄]⁴⁺ cage from ditopic ligand 1 and [PdPy*₄](OTf)₂. Due to the conformational flexibility of 1, 1 adopts C- and S-shaped conformations in solution. In the absence of a good template (NO₃⁻), oligomerization is preferred from S-shaped ligands to lead to a kinetically trapped micrometer-sized sheet structure (off-pathway). The sheet can be converted to the thermodynamically stable [Pd₂1₄]⁴⁺ cage by a good template, NO₃⁻. The cage can be produced through the other pathway in the presence of NO₃⁻ (on-pathway), where the C-shaped conformation is induced by the template to form the (NO₃⁻)@[Pd₂1₂Py*₄]⁴⁺ cyclic structure