Trefoiled Propeller-Shaped Spiral Terpyridyl Metal-Organic Architectures.

Constructing exquisite and intricate molecular architectures is always the pursuit of chemists. In this report, the propeller-shaped trefoil structures S1 and S2 were successfully prepared by the stepwise self-assembly of predesigned tripodal metal-organic ligands, which consist of bis(terpyridine)s-Ru2+-tris(terpyridine)s connectivities for the following complexation with Fe2+. The complexes can be described as racemic spiral assemblies with three-fold spiralism. These unique discrete metal-organic architectures were fully characterized by 1H NMR, 2D NMR spectroscopy (COSY and NOESY), diffusion-ordered NMR spectroscopy (DOSY), ESI-MS, TWIM-MS, and TEM, and their photophysical and electrochemical properties were also investigated. Further, hybrid trefoiled structure [Fe3L1L2] was detected by taking advantage of the flexibility of metal-organic ligands.