Templation and Concentration Drive Conversion Between a FeL Pseudoicosahedron, a FeL Tetrahedron, and a FeL Helicate.

We report the construction of three structurally distinct self-assembled architectures: FeL pseudoicosahedron , FeL helicate , and FeL tetrahedron , formed from a single triazatriangulenium subcomponent under different reaction conditions. Pseudoicosahedral capsule is the largest formed through subcomponent self-assembly to date, with an outer-sphere diameter of 5.4 nm and a cavity volume of 15 nm. The outcome of self-assembly depended upon concentration, where the formation of pseudoicosahedron was favored at higher concentrations, while helicate exclusively formed at lower concentrations. The conversion of pseudoicosahedron or helicate into tetrahedron occurred following the addition of a CBH or BF template.