Molecular Tectonics: Design of Enantiopure Luminescent Heterometallic Ir(III)–Cd(II) Coordination Network

With the aim of combining luminescence
and chirality in heterometallic Ir­(III)–Cd­(II) coordination
networks, synthetic strategies for the formation of new Ir­(III)-based
chiral metallatectons ([Ir­(dFppy)2(1)]­[PF6]), both as a racemic mixture of Δ and Λ enantiomers
(rac-[Ir­(dFppy)2(1)]­[PF6]) and as enantiopure complexes (Δ-[Ir­(dFppy)2(1)]­[PF6] and Λ-[Ir­(dFppy)2(1)]­[PF6]), were developed. The final compounds
were characterized both in solution and in the crystalline phase.
Notably, their crystal structures were determined by single crystal
X-ray diffraction, and their photophysical properties in solution
and in the solid state were investigated. Combination of the cationic
linear metallatecton with Cd2+ iodide salt ([CdI3]−), behaving as an anionic two-connecting node,
leads to the formation of 1D chiral and neutral heterometallic Ir­(III)–Cd­(II)
luminescent coordination networks both as a racemic mixture and as
enantiomerically pure infinite architectures. The latter have been
structurally studied in the solid state by X-ray diffraction both
on single crystals and on microcrystalline powders. The infinite coordination
networks display phosphorescence in the solid state at ca. 600 nm
upon excitation at 400 nm.