Sensing, templation and self-assembly by macrocyclic ligand systems

For a number of years the research interests of the Beer group have covered many areas of macrocyclic coordination and supramolecular chemistry. This article reviews our latest results of current research by focusing on three major sections: sensing of cations and anions; anion templated assembly of pseudorotaxanes and rotaxanes, and metaldirected self-assembly using the dithiocarbamate ligand. © 2005 Springer. Printed in the Netherlands

Sensing, templation and self-assembly by macrocyclic ligand systems

For a number of years the research interests of the Beer group have covered many areas of macrocyclic coordination and supramolecular chemistry. This article reviews our latest results of current research by focusing on three major sections: sensing of cations and anions; anion templated assembly of pseudorotaxanes and rotaxanes, and metaldirected self-assembly using the dithiocarbamate ligand. © 2005 Springer. Printed in the Netherlands

Acyclic and macrocyclic transition metal dithiocarbamate complexes containing imidazolium moieties for anion binding

The synthesis of acyclic and macrocyclic transition metal dithiocarbamate complexes containing positively charged imidazolium moieties is reported. The assemblies have been characterised by a range of spectroscopic techniques and the ability of these compounds to bind various anions was also examined. The synthesis of acyclic and macrocyclic transition metal dithiocarbamate complexes containing positively charged imidazolium moieties is reported. The assemblies have been characterised by a range of spectroscopic techniques and the ability of these compounds to bind various anions was also examined. UV-Vis spectroscopic binding studies revealed H2PO4- is complexed selectively in preference to F - and Cl - for the acyclic transition metal dithiocarbamate complexes containing the N-methylimidazolium moiety. Cyclic voltammetric studies demonstrated that the copper(II) dithiocarbamate imidazolium systems can electrochemically sense the binding of Cl - and H 2PO 4-. © 2004 Elsevier Ltd. All rights reserved

Efficient light harvesting of a luminescent solar concentrator using excitation energy transfer from an aggregation-induced emitter

The compromise between light absorption and reabsorption losses limits the potential light conversion efficiency of luminescent solar concentrators (LSCs). Current approaches do not fully address both issues. By using the excitation energy transfer (EET) strategy with a donor chromophore that exhibits aggregation-induced emission (AIE) behaviour, it is shown that both transmission and reabsorption losses can be minimized in a LSC device achieving high light collection and concentration efficiencies. The light harvesting performance of the LSC developed has been characterized using fluorescence quantum yield measurements and Monte Carlo ray tracing simulations. Comparative incident photon conversion efficiency and short-circuit current data based on the LSC coupled to a silicon solar cell provide additional evidence for improved performance

Regioselective synthesis of fullerene multiadducts via tether-directed 1,3-dipolar cycloaddition

The regioselective synthesis of fullerene multiadducts was achieved from commercially available reagents in one pot over two steps. The configuration of the isolated regioisomers was determined using various NMR methods, UV-vis spectroscopy and electrochemical analysis with the structure of one isomer confirmed by single crystal X-ray analysis. Interesting variation in regioselectivity was observed when different amino acid reagents were used in the reactions. Theoretical calculations and additional experiments, such as deuterium exchange, led to a proposed mechanism for the regioselective product formation

Concentrating Aggregation-Induced Fluorescence in Planar Waveguides: A Proof-of-Principle

The photophysical properties of fluorescent dyes are key determinants in the performance of luminescent solar concentrators (LSCs). First-generation dyes--coumarin, perylenes, and rhodamines--used in LSCs suffer from both concentration quenching in the solid-state and small Stokes shifts which limit the current LSC efficiencies to below theoretical limits. Here we show that fluorophores that exhibit aggregation-induced emission (AIE) are promising materials for LSC applications. Experiments and Monte Carlo simulations show that the optical quantum efficiencies of LSCs with AIE fluorophores are at least comparable to those of LSCs with first-generation dyes as the active materials even without the use of any optical accessories to enhance the trapping efficiency of the LSCs. Our results demonstrate that AIE fluorophores can potentially solve some key limiting properties of first-generation LSC dyes