Supramolecular chemistry: Self-assembly of titanium based molecular squares

The interaction of Cp₂TiCl₂ with LiC₅H₅N and LiC₁₁H₈N provides Cp₂Ti(Cl)(C₅H₅N) and Cp₂Ti(Cl)(C₁₁H₈N), respectively. Reaction of these species with AgOSO₂CF₃ results in self-assembly of the respective cationic, tetranuclear molecular squares where the required 90° bond angles, demanded by a rectangle, is provided by the distorted tetrahedral bond angles of the coordinated Ti.