Datensatz

Zusammenfassung

Reaction of [(η⁵‐Me₄EtC₅)Fe^IICl(tmeda)] (tmeda=N,N,N′N′‐tetramethylethylenediamine) with a polyanion solution of decacyclene (1) results in the formation of the triple‐deckers [{(η⁵‐Me₄EtC₅)Fe}₂‐μ₂‐(η⁶:η⁶‐decacyclene)] (3) and [{(η⁵‐Me₄EtC₅)Fe}₄‐μ₄‐(η⁶:η⁶:η⁶:η⁶‐decacyclene)] (4). Metal complexation in 3 and 4 occurs on opposite faces of the π perimeter in an alternating mode. The decacyclene ring adopts a gently twisted molecular propeller geometry with twofold crystallographic symmetry (C₂). Complex 4 crystallizes in the chiral space group C222₁; the investigated crystal only contains decacyclene rings with M chirality. The handedness can be assigned unambiguously to the presence of the iron atoms. Cyclovoltammetric studies revealed quasireversible behavior of the redox events and a strong interaction of the Fe atoms in 3 and 4, exemplified by potential differences ΔE of 660 and 770(780) mV between the first and the second individual oxidation processes. This corresponds to a high degree of metal–metal interaction for 3 and 4. The sucesssful syntheses of 3 and 4 together with earlier results from our laboratory proves that all five‐ and six‐membered π subunit sets of 1 are prone to metal complexation. A clear site preference in 1 towards the complexation of [Cp^R]iron, ‐cobalt, and ‐nickel fragments exists.