Stereocontrolled Self-Assembly of Ln(III)-Pt(II) Heterometallic Cages with Temperature-Dependent Luminescence.

Structurally well-defined discrete d/f heterometallic complexes show diverse application potential in electrooptic and magnetic materials. However, precise control of the component and topology of such heterometallic compounds with fine-tuned photophysical properties is still challenging. Herein, we report the stereocontrolled syntheses of a series of Ln III -Pt II heterometallic cages through coordination-driven self-assembly of enantiopure alkynylplatinum-based metalloligands (L 1 R / S , L 2 R / S ) with lanthanide ions (Ln = Eu III , Yb III , Nd III , Lu III ). Taking advantage of the metal-to-ligand charge transfer (MLCT) excited state on the designed alkynylplatinum ligands, the excitation window for the sensitized near-infrared (NIR) luminescence on the Yb III - and Nd III -containing cages can be extended to the visible region (up to 500 nm). Linear temperature-dependent red and NIR emissions observed on the Ln 4 (L 2 R / S ) 6 (Ln III = Eu III and Yb III , respectively) complexes suggest their potential applications as luminescent temperature sensors, with sensitivities of -0.54% (Ln III = Eu III , 77-250 K) and -0.17% (Ln III = Yb III , 77-300 K) per K achieved. This work not only offers a good strategy to prepare new d/f heterometallic supramolecular cages but also paves the way for the design of stimuli-responsive luminescent materials.