Insoluble lithium complex of polyether carboxylic acids consisting of naphthalene repeating unit and its stable monolayer on aqueous surfaces

We synthesized several polyether dicarboxylic acids with naphthalene and tr imethylene groups as repeating units. The polyethers selectively formed com plexes with lithium, an alkali metal. In contrast to the typical polyethers , their alkali metal complexes exhibited very low solubilities for water an d hydrophobic organic solvents such as chloroform and toluene. Polyethers h aving seven naphthalene units formed a stable monolayer on an aqueous subph ase, only when alkali metal hydroxides were added, but not acid.