Chiral recognition between dissymmetric (Ln dpa 3)3- and Co(III)-nucleotide complexes in aqueous solution. Enantioselective luminescence quenching as a probe of intermolecular chiral discrimination

The enantioselective quenching of (Ln dpa 3)3- luminescence by Co(III) complexes with four NH3 ligands and one nucleotide ligand was investigated. Circularly polarized luminescence measurements revealed that small concentrations of dissymmetric quencher molecules in a solution with a racemic excited-state population of luminophores can yield a significant enantiomeric excess in the Ln* population. The degree of enantioselectivity is higher than expected and there exists a significant variation in the relative sign of E(sub q) values.