Cap for Copper(I) Ions! Metallosupramolecular Solid and Solution State Structures on the Basis of the Dynamic Tetrahedral [Cu(phenAr₂)(py)₂]⁺ Motif

Abstract

The tetrahedral [Cu(phenAr(2))(py)(2)](+) coordination motif (phen = 1,10-phenanthroline; py = pyridine) conceived on the basis of the HETPYP concept (heteroleptic pyridyl and phenanthroline metal complexes) is a versatile dynamic unit for constructing various heteroleptic metallosupramolecular pseudo-1D, 2D, and 3D structures, both in solution and the solid state. The 2,9-diaryl substituted phenanthroline (phenAr(2)) serves as a capping ligand for copper(I) ions, as its bulky nature prevents formation of the homoleptic complex [Cu(phenAr(2))(2)](+). Combination of the dynamic and concave metal ligand building block [Cu(phenAr(2))](+) with various pyridine (py) ligands, such as bi-, tri-, and tetra-pyridines, opened the way to infinite 1D helicates, 2D networks, and discrete 3D hexanuclear cages, whereas spatial integration of both phenAr(2) and py units into a single ligand resulted in the formation of a Borromean-ring-type hexanuclear cage.

Star-Shaped Conjugated Systems

“…For example carboxylate substituted derivatives 24i (E = COO - , n = 2) were applied to produce metal-organic frameworks (MOF‘s) [102], star scaffolds with peripheral metal complexes were investigated with respect to their intramolecular energy transfer [103,104] and stars with peripheral amino acid substituents as biological active materials were synthesized [105]. The parent structures 24a-c were studied with respect to their potential as laser dyes [62].…”

Self-assembly of heteroleptic dinuclear metallosupramolecular kites from multivalent ligands via social self-sorting

“…Unfortunately, the selective formation of heteroleptic complexes from a mixture of different multivalent ligands bridging two or more metal ions is more challenging and there is only a limited number of reliable protocols available yet [6–7]. These comprise (i) topological control pioneered by J. P. Sauvage [8], (ii) steric control as first established by M. Fujita [9] and P. J. Stang [10] using pyridine and lutidine-based ligands or in M. Schmittel’s HETPHEN [11], HETTAP [12], and HETPYP concepts [13], (iii) metal coordination specifics as pioneered by J.-M. Lehn with metal centers that prefer five-fold coordination [14], or (iv) charge-separation effects as utilized by P. J. Stang [15]. …”

An infinite chainmail of M6L6 metallacycles featuring multiple Borromean links

“…Borromean assemblies where three macrocyclic ligands have a Borromean association but are held together through endo and exo metal-ligand coordination are also known 17,29,30 and may be a precursor to "real" Borromean rings. 16 Conceptually similar but topologically non-complex ring-inring assemblies with two macrocycles have been reported as steps towards Borromean rings.…”