Enantioselective recognition of α-hydroxycarboxylic acids and N-Boc-amino acids by counterion-displacement assays with a chiral nickel(II) complex.

A new chiral sensor based on an N,N'-dioxide nickel(II) complex was prepared, which could visually recognize a series of chiral α-hydroxycarboxylic acid enantiomers by coordination and self-assembly forming into nanospheres or nanofibers. With the help of various techniques, the morphology structures of the colloid or suspension were obtained and the counterion-displacement assays were also confirmed. In addition, this metal complex could act as a highly enantioselective fluorescence sensor to recognize N-Boc-amino acids and chiral α-hydroxycarboxylic acids.