A Zn(II) Metallocycle as Platform to Assemble a 1D + 1D → 1D Polyrotaxane via π···π Stacking of an Ancillary Ligand

Abstract

A new [Zn2L2] metallocycle bearing two metal centers that can coordinate ancillary ligands and a pocket suitable to host guest molecules is reported. These two features are exploited by reacting the metallocycle with a pyridine ligand to self-assemble in the solid state an extended intertwined system with the rare 1D + 1D → 1D topology. This interpenetrated architecture is supported by π···π stacking between two pyridine units of two different metallocycles in the pocket of a third metallocycle.

Dynamic lanthanide exchange between quadruple-stranded cages: the effect of ionic radius differences on kinetics and thermodynamics

“…Oligo-β-diketones are versatile ligands for the preparation of metallo-supramolecular architectures 37,38 ranging from metallocycles, cages and MOFs, [39][40][41][42][43] to triple-and quadruplestranded helicates [44][45][46][47][48][49][50][51][52][53] and even to interlocked structures. [54][55][56][57] Recently, we reported two [Ln 2 L 4 ] 2− quadruple-stranded helicates (Ln = La, Eu and Gd) that show dynamic and adaptive helicity reorganization due to a guest-to-host chirality transfer. 44 Herein, by using a closely related bis-β-diketone ligand, we report a larger series of seven [Ln 2 L 4 ] 2− quadruple-stranded helicates (Ln = La, Nd, Eu, Tb, Er, Tm and Lu), Fig.…”

Dynamic lanthanides exchange between quadruple-stranded cages: effect of ionic radius differences on kinetics and thermodynamics

“…Oligo-β-diketones are versatile ligands for the preparation of metallo-supramolecular architectures 38,39 ranging from metallocycles, cages and MOFs, [40][41][42][43][44] to helicates 37,[45][46][47] and even to interlocked structures. [48][49][50] Herein, by using a close related bis-β-diketone ligand, we present a larger series of seven [Ln2L4] 2− quadruple-stranded helicates (Ln = La, Nd, Eu, Tb, Er, Tm and Lu), Figure 1, that once assembled undergo transmetalation. The thermodynamics and kinetics of the dynamic ion exchange has been studied and the role of the Ln 3+ ΔEIR evaluated.…”