Enantioselective fluorescence sensing of chiral alpha-amino alcohols

1,8-Bis(3-tert-butyl-9-acridyl)naphthalene N, N'-dioxide, 1, has been synthesized in five steps from 3-tert-butylaniline and 2-chlorobenzoic acid in 29% overall yield. This C 2-symmetric ligand forms a highly fluorescent scandium complex that can be used for enantioselective sensing of chiral amino alcohols. A fluorescence ligand displacement assay that allows accurate measurements of both the total amount and the enantiomeric excess of several amino alcohols at micromolar concentrations is reported.