Five-component, one-pot synthesis of an electroactive rotaxane comprising a bisferrocene macrocycle.

The templated clipping of a ferrocene-grafted isophthalic acid derivative to encircle a hydrogen-bonding axle through the reaction with 1,4-bis(aminomethyl)benzene is described. The constituent electroactive macrocycle of the resultant [2]rotaxane is a homologue of the versatile benchmark tetraamide variant developed by Leigh and co-workers. The relative templating effect of different hydrogen-bonding motifs in rotaxane and pseudorotaxane generation is compared, with yields varying from 0 to 41%. The electrochemical properties and single crystal X-ray structure of a doubly ferrocene-decorated [2]rotaxane are further reported.

Planar 2-Pyridyl-1,2,3-triazole Derived Metallo-ligands: Self-assembly with PdCl2 and Photocatalysis.

Self-assembled metallosupramolecular architectures (MSAs) with built-in functionalities such as light-harvesting metal centers are a promising approach for developing emergent properties within discrete molecular systems. Herein we describe the synthesis of two new but simple "click" ligands featuring a bidentate 2-pyridyl-1,2,3-triazole chelate pocket linked to a monodentate pyridyl (either 3- or 4-substituted, L1 and L2) unit. The ligands and the corresponding four PdII and PtII metallo-ligands (Pd1, Pd2, Pt1 and Pt2) were synthesized and characterized using nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization mass spectrometry (ESI-MS), and X-ray crystallography. Solid-state characterization of the series of ligands and metallo-ligands revealed that these compounds display a co-planar conformation of all the aryl units. The PtII containing metallo-ligands (Pt1 and Pt2) were found to assemble into square (Sqr) and triangular (Tri) shaped architectures when combined with neutral PdCl2 linker units. Additionally, the ability of the PtII metallo-ligands and Tri to photocatalyze the cycloaddition of singlet oxygen to anthracene was investigated.

Functional metal complexes from CuAAC "click" bidentate and tridentate pyridyl-1,2,3-triazole ligands.

Ligands containing the bidentate 2-pyridyl-1,2,3-triazole and tridentate 2,6-pyridyl-bis(1,2,3-triazole) moieties have emerged as alternatives to 2,2'-bypridine and 2,2':6',2''-terpyridine and other nitrogen-containing bi- and tri-dentate chelators. Because these "click" ligands are readily functionalised they are attractive options for the development of functional coordination complexes. This Frontiers Article discusses key recent reports on functional CuAAC "click" complexes in the areas of biological agency, photophysics, and catalysis.