Collection of Czechoslovak Chemical Communications - digital archive 

Abstract

Photochemically generated cationic cyclopentadienyl iron fragments [FeCp]⁺ allow a specific stacking reaction of [(t-Bu₃C₃P₂)Fe(t-Bu₂C₂P₃)]. This results in the transient formation of an unstable cationic Fe-Fe triple-decker sandwich complex which decomposes by deliberating the neutral sandwich complex [CpFe(t-Bu₂C₂P₃)], and is stacked again by a second [FeCp]⁺-unit, yielding the moderately stable cationic triple-decker sandwich complex [CpFe(t-Bu₂C₂P₃)FeCp]⁺ with a central mi-eta⁵:eta⁵-triphospholyl ligand. Air exposure or storage of solutions at room temperature leads to a destacking and the neutral triphosphaferrocene derivative [CpFe(t-Bu₂C₂P₃)] is formed again almost quantitatively in respect to the pentaphospha-ferrocene educt.

Keywords: Iron compounds; Triple-Decker sandwich complexes; Triphospholyl complexes.