[2]Pseudorotaxane and [2]Rotaxane Molecular Shuttles:  Self-Assembly through Second-Sphere Coordination of Thiocyanate Ligands

Abstract

A Pd(Py)(2)(SCN)(2) complex is shown to form a [2]pseudorotaxane complex with a macrocyclic tetralactam, which binds in the solid state through an unexpected complexation geometry. The intermolecular complexation is further applied to template the formation of a [2]rotaxane. The interlocked product acts as a degenerate molecular shuttle in solution, which is consistent with the co-conformation observed in the solid state.