Adaptive Coordination-Driven Supramolecular Syntheses toward New Polymetallic Cu(I) Luminescent Assemblies

Area of Science:

• Supramolecular Chemistry
• Coordination Chemistry
• Materials Science

Background:

• Thermally activated delayed fluorescence (TADF) materials are crucial for efficient organic light-emitting diodes (OLEDs).
• Developing versatile precursors for constructing complex metallo-supramolecular architectures remains a significant challenge in materials science.

Purpose of the Study:

• To synthesize and characterize a conformationally adaptive TADF tetrametallic copper(I) metallacycle (A) as a precursor.
• To explore the coordination-driven supramolecular assembly of A with cyano-based building blocks.
• To investigate the luminescent properties of the resulting polymetallic assemblies, particularly heterobimetallic derivatives.

Main Methods:

• Synthesis of a tetrametallic copper(I) metallacycle precursor (A).
• Coordination-driven self-assembly reactions with various cyano-based ligands.
• Characterization of the resulting coordination polymer (C) and heterobimetallic assemblies (D_M) using spectroscopic and crystallographic techniques.
• Photophysical studies to evaluate luminescence behavior and structure-property relationships.

Main Results:

• Metallacycle A successfully serves as a precursor for generating diverse room-temperature solid-state luminescent polymetallic assemblies.
• A homometallic 1D-helical coordination polymer (C) and discrete circular heterobimetallic assemblies (D_M, M = Ni, Pd, Pt) were synthesized.
• The photophysical properties of D_M assemblies are significantly influenced by the spin-orbit coupling of the central metal (M) center.

Conclusions:

• A conformationally adaptive TADF copper(I) metallacycle is a versatile platform for constructing complex luminescent supramolecular structures.
• The strategic incorporation of heavy metal centers (Ni, Pd, Pt) in heterobimetallic assemblies allows for tuning of photophysical properties via spin-orbit coupling.
• This work provides a rational approach for designing advanced luminescent materials with tailored properties for potential optoelectronic applications.