A Broadened Class of Donor‐Acceptor Stacked Macrometallacyclic Adducts of Different Coinage Metals

Abstract

AbstractA yet‐outstanding supramolecular chemistry challenge is isolation of novel varieties of stacked complexes with finely‐tuned donor‐acceptor bonding and optoelectronic properties, as herein reported for binary adducts comprising two different cyclic trinuclear complexes (CTC@CTC’). Most previous attempts focused only on 1–2 factors among metal/ligand/substituent combinations, resulting in heterobimetallic complexes. Instead, here we show that, when all 3 factors are carefully considered, a broadened variety of CTC@CTC’ stacked pairs with intuitively‐enhanced intertrimer coordinate‐covalent bonding strength and ligand‐ligand/metal‐ligand dispersion are attained (dM–M’ 2.868(2) Å; ΔE>50 kcal/mol, an order of magnitude higher than aurophilic/metallophilic interactions). Significantly, CTC@CTC’ pairs remain intact/strongly‐bound even in solution (Keq 4.67×105 L/mol via NMR/UV‐vis titrations), and the gas phase (mass spectrometry revealing molecular peaks for the entire CTC@CTC’ units in sublimed samples), rather than simple co‐crystal formation. Photo‐/electro‐luminescence studies unravel metal‐centered phosphorescence useful for novel all metal‐organic light‐emitting diodes (MOLEDs) optoelectronic device concepts. This work manifests systematic design of supramolecular bonding and multi‐faceted spectral properties of pure metal‐organic macrometallacyclic donor/acceptor (inorganic/inorganic) stacks with remarkably‐rich optoelectronic properties akin to well‐established organic/organic and organic/inorganic analogues.