Precise Self-Assembly of Molecular Four- and Six-Pointed Stars.

A novel metal-organic ligand (MOL 2) has been prepared by linking two V-shaped bis-terpyridines with one X-shaped tetrakis-terpyridine through the stable <tpy-Ru2+-tpy> connectivity. The complexation between MOL 2, X-shaped tetrakis-terpyridine, and Zn2+ gave rise to a supramolecular C6-symmetrical six-pointed star quantitatively. In addition, a mixture of MOL 2, K-shaped tetrakis-terpyridine, and Zn2+ afforded a C2-symmetrical four-pointed star. These metallo-supramolecular architectures were adequately characterized by NMR, ESI-MS, TWIM-MS, and TEM analyses.