Experimental and theoretical study on cation–π interaction of the univalent thallium cation with [2.2.2]paracyclophane

Abstract

By using electrospray ionization mass spectrometry (ESI-MS), it was proven experimentally that the univalent thallium cation (Tl+) forms with [2.2.2]paracyclophane (C24H24) the cationic complex species [Tl(C24H24)]+. Further, employing quantum mechanical DFT calculations, the most probable structure of the [Tl(C24H24)]+ complex was derived. In the resulting complex with a symmetry very close to C3, the ‘central’ cation Tl+ is bound by six bonding interactions to six carbon atoms from the three benzene rings of the parent [2.2.2]paracyclophane ligand via cation–π interaction.