Self-Assembly of a Pd₄L₈ Double-Walled Square Takes Place through Two Kinds of Metastable Species

The self-assembly process of a Pd4L8 double-walled square (DWS) was investigated. As was seen in Pd2L4 cages, Pd­(II)-linked coordination self-assembly processes are generally affected by the rigidity of multitopic ligands. However, the self-assembly of a Pd4L8 DWS from rigid ditopic ligands took place with the formation of two kinds of metastable species [submicrometer-sized species and a Pd3L6 double-walled triangle (DWT)]. This result suggests that the self-assembly process of the DWS is largely affected by the geometry of the final product and not by that of the ditopic ligand