Imidazolium-functionalized BINOL as a multifunctional receptor for chromogenic and chiral anion recognition.

A novel imidazolium-functionalized BINOL fluorescent receptor R-1 was developed as a multifunctional receptor for both chromogenic and chiral anion recognition. The different fluorescent responses and color changes of R-1 could be applied to the detection of fluoride and acetate ions by the naked eye. Furthermore, the chiral recognition of the two enantiomers of alpha-amino carboxylates was also studied, and R-1 displayed a remarkable binding ability for the t-Boc alanine anion with an interesting enantioselectivity (K(L)/K(D) = 4.5).