Reinforcement of guest selectivity through the self-assembly of host molecules: selective recognition of lithium ions by dimerizable tricarboxylic acids.

C3-Symmetric tricarboxylic acids form dimers through intermolecular hydrogen bonds in nonpolar organic solvents. These dimers recognize lithium ions with high selectivities through the formation of 1 : 1 host-guest complexes between the collapsed dimeric assemblies and guest molecules.