Directed Self‐Assembly of Chiral, Optically Active Macrocyclic Tetranuclear Molecular Squares

Exclusive formation of one of the six possible diastereomers (see formula on the right) is observed in the near-quantitative self-assembly of optically active tetranuclear molecular squares from a mixture of the corresponding triflate bisphosphane transition metal complexes and diaza ligands. Asymmetric induction through the chiral bisphosphane ligands and restricted rotation about the bonds between the metal centers and the nitrogen atoms of the heteroarene ligands play vital roles.