Aidan G. Young

Bio: Aidan G. Young is an academic researcher from University of Otago. The author has an hindex of 1, co-authored 1 publications receiving 186 citations.

A multicomponent CuAAC “click” approach to a library of hybrid polydentate 2-pyridyl-1,2,3-triazole ligands: new building blocks for the generation of metallosupramolecular architectures

Abstract: A one pot, multicomponent CuAAC reaction has been exploited for the safe generation of alkyl, benzyl or aryl linked polydentate pyridyl-1,2,3-triazole ligands from their corresponding halides, sodium azide and alkynes in excellent yields. The ligands have been fully characterised by elemental analysis, HR-ESMS, IR, 1H and 13C NMR and in two cases the structures were confirmed by X-ray crystallography. Additionally, we have examined the Ag(I) coordination chemistry of these ligands and found, using HR-ESMS, 1H NMR, and X-ray crystallography, that both discrete and polymeric metallosupramolecular architectures can be formed.

From Widely Accepted Concepts in Coordination Chemistry to Inverted Ligand Fields.

Abstract: We begin with a brief historical review of the development of our understanding of the normal ordering of nd orbitals of a transition metal interacting with ligands, the most common cases being three below two in an octahedral environment, two below three in tetrahedral coordination, and four below one in a square-planar environment. From the molecular orbital construction of these ligand field splittings evolves a strategy for inverting the normal order: the obvious way to achieve this is to raise the ligand levels above the metal d’s; that is, make the ligands better Lewis bases. However, things are not so simple, for such metal/ligand level placement may lead to redox processes. For 18-electron octahedral complexes one can create the inverted situation, but it manifests itself in the makeup of valence orbitals (are they mainly on metal or ligands?) rather than energy. One can also see the effect, in small ways, in tetrahedral Zn(II) complexes. We construct several examples of inverted ligand field syst...

Deciphering synergetic core-shell transformation from [Mo 6 O 22 @Ag 44 ] to [Mo 8 O 28 @Ag 50 ].

Abstract: The structural transformation of high-nuclearity silver clusters from one to another induced by specific stimuli is of scientific significance in terms of both cluster synthesis and reactivity. Herein, we report two silver-thiolate clusters, [Mo6O22@Ag44] and [Mo8O28@Ag50], which are templated by isopolymolybdates inside and covered by iPrS− and PhCOO− ligands on the surfaces. Amazingly, the [Mo8O28@Ag50] can be transformed from [Mo6O22@Ag44] by adding PhCOOH which increases the degree of condensation of molybdates template from Mo6O228- to Mo8O288-, then enlarging the outer silver shell from Ag44 to Ag50. The evolution of solution species revealed by time-dependent electrospray ionization mass spectrometry (ESI-MS) suggests a breakage-growth-reassembly (BGR) transformation mechanism. These results not only provide a combined assembly strategy (anion-template + induced transformation) for the synthesis of silver-thiolate clusters but also help us to better understand the complex transformation process underpinning the assembly system. Understanding how one metal nanocluster transforms into another is of synthetic and fundamental importance. Here, the authors use mass spectrometry to reveal an acid-induced structural transformation between two Ag clusters that proceeds via a breakage-growth-reassembly mechanism.

Solvent or temperature induced diverse coordination polymers of silver(I) sulfate and bipyrazole systems: syntheses, crystal structures, luminescence, and sorption properties.

Abstract: Three new coordination polymers, [Ag4(H2bpz)4(SO4)2]·H2O (1), [Ag2(H2bpz)2(SO4)]·3H2O (2), and [Ag3(H2bpz)4](SO4)2/3(OH)5/3·4H2O (3) have been solvothermally synthesized with Ag2SO4 and flexible ligand 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (H2bpz) in different solvents and temperatures. Complex 1 is a 2-fold interpenetrated three-dimensional (3D) framework with an uncommon (3,5)-connected hms topology. Complex 2 is a structural isomer of 1 and shows a three-connected 2D ths net consisting of interesting 3-fold and 2-fold heterochiral helical chains. Complex 3 discloses a grid layer structure, containing heterochiral helical chains and an unusual meso-helix. More interestingly, three sets of layers in 3 stack in different directions, affording an unprecedented 2D + 2D + 2D → 3D polycatenating cationic framework with 1D + 3D porous systems. In 1–3, H2bpz exhibit exobidentate bridging fashions with wide-ranged interpyrazole tilting angles and changeable coordination configurations, such as cis and trans fash...