Pair of chiral 2D silver(I) enantiomers: chiral recognition of L- and D-histidine via differential pulse voltammetry.

Abstract

Self-assembly of AgPF6 with a pair of chiral tridentate ligands (1S,1'S,1''S,2R,2'R,2''R) and (1R,1'R,1''R,2S,2'S,2''S)-(benzenetricarbonyltris(azanediyl))tris(2,3-dihydro-1H-indene-2,1-diyl)triisonicotinate (s,r-L) and (r,s-L) in a mixture of methanol and dioxane yields 2D sheets consisting of [Ag(s,r-L)](PF6)·3C4H8O2·0.5H2O and [Ag(r,s-L)](PF6)·3C4H8O2·0.5H2O, respectively. The differential pulse voltammetric (DPV) technique using the pair of chiral 2D-sheet enantiomers was employed for chiral discrimination of amino acid enantiomers, and was found to be an effective tool for enantio-recognition of L- and D-histidines. Both the size and the binding site of amino acids were strongly dependent on electrochemical enantio-recognition via the chiral 2D sheets.