Synthesis and properties of biphenyl-containing fluorenonophanes

A novel family of crownophanes containing 2,7-dioxyfluorenone and 4,4′-dioxybiphenyl fragments linked by tri- and tetraethylene glycol residues was obtained. The formation of pseudorotaxanes in reactions of these ligands with paraquat hexafluorophosphate was detected by FAB mass spectrometry, 1H NMR spectroscopy, and electronic absorption spectroscopy.