Synthesis, structure and properties of the macrocyclic ferrocenophanes with cyclopentadienyl ligands tethered by oligo(ethylene glycol) chain

Cyclization reactions of Fe{C5H4OCH2(CH2OCH2)nCH2OTs}2 (n = 1, 2) with C6H4-1,2-(OH)2, C6H4-1,3-(OH)2, and Fe(C5H4OAc)2 under basic conditions yield the corresponding macrocyclic 1,1′-ferrocenophanes. The ferrocenophane having a pyrido-crown ether structure was also synthesized. These ferrocenophanes were characterized by X-ray crystallography and NMR spectroscopy. Cyclic voltammograms of the ferrocenophanes exhibited reversible redox peaks assigned to the oxidation and reduction of the ferrocene unit. The macrocyclic pyrido-containing ferrocenophane forms pseudorotaxane with [NH2{(CH2)9Me}2]BARF (BARF = B{C6H3-3,5-(CF3)2}4) in CDCl3.