abstract
Three triazolium-based [2]rotaxanes containing different sized axle and macrocycle components were synthesised in good yields (40-57%) through chloride anion templation. The anion recognition properties of the interlocked receptor systems were investigated using (HNMR)-H-1 titration experiments: all three rotaxanes display impressive selectivities for halide anions over the more basic oxoanion acetate. The rotaxanes incorporating shorter, more rigid axle components with aryl-substituted triazolium groups display substantially higher anion binding affinities than those with longer, bis-alkyl-substituted heterocycles, which is attributed to the increased intercomponent preorganisation afforded by the smaller axle component. Computational DFT and molecular dynamics simulations composed of unconstrained and umbrella sampling simulations corroborate the experimental observations.
keywords
ANION RECOGNITION; HYDROGEN-BONDS; MACROCYCLIC RECEPTOR; COMPUTER-PROGRAM; TERMINAL ALKYNES; AQUEOUS-MEDIA; ARYL-TRIAZOLE; BINDING; CHLORIDE; COMPLEXES
subject category
Chemistry
authors
White, NG; Costa, PJ; Carvalho, S; Felix, V; Beer, PD
our authors
Paulo Jorge Ferreira de Matos Costa
Post-doc Fellowship
Sílvia Cristina Ferreira de Carvalho
Post-doc Fellowship
Vítor Félix
Associate Professor with Aggregationacknowledgements
We thank Oxford Chemical Crystallography for instrumentation, Diamond Lightsource for an award of beamtime on Beamline I19, Dr.David Allan (Diamond Lightsource) for assistance with the structure of