Selective complexation between a novel bowl-shaped molecule and Fe3+ or ions

We report the selective association of a novel bipolarofacial, bowl-shaped molecule (I) with Fe3+ and PdCl 4 2 - ions. UV–vis titration experiments and Langmuir isotherm measurements revealed stronger association with the palladate over the iron ions, both in homogeneous organic medium as well as at the air–water interface. Interestingly, we found that the complexation is solvent-dependent, suggesting that I undergoes isomerization prior to association with the metal ions.