Ring a bell: Disubstituted calix[4]arene as ligand for transition metal chlorides

Lower rim 1,3-disubstituted p-tert-butylcalix[4]arene is studied here in its deprotonated form as complexing ligand for iron and chromium chloride. Crystallization of the two complexes from dry THF gives two different stoichiometries and structures, a trinuclear iron compound and a second, mononuclear structure with chromium. In both cases, the ligand adopts an elliptical shape and the metal ions are bound to the lower rim of the calixarene molecule.

Graphical abstractTwo complexes of disubstituted calix[4]arene has been characterized by X-ray single crystal diffraction. These complexes have two different stoichiometries and structures, a trinuclear iron compound and a second, mononuclear structure with chromium. In both cases, the ligand adopts an elliptical shape and the metal ions are bound to the lower rim of the calixarene molecule.Figure optionsDownload full-size imageDownload as PowerPoint slide