First C₄bridged mixed-valence iron(II)–iron(III) complex delocalized on the infrared timescale

Ligand Redox Non‐Innocence in Transition‐Metal σ‐Alkynyl and Related Complexes

“…[109] Crystallisation of the resulting reaction mixture afforded [{Fe(dppe)Cp} 2 {μ-C=C(R) [109] and later ferrocenium [110] ) or anodic oxidation [109] were unsuccessful, although it was ultimately demonstrated that accumulation of alkynyl radical cations by chemical oxidation at low temperatures can lead to more effective C-C coupling. [111] Alkynyl radical coupling to form bis(vinylidene) species generally occurs in competition with the hydrogen-abstraction pathway, and the relative extent of dimerisation versus hydrogen abstraction is subject to thermodynamic and/or kinetic (steric) factors. [112] These competing pathways of oxidation, hydrogen atom abstraction and C β -C β coupling are clearly illustrated in the behaviour of complexes [Mo(CϵCR)(dppe)(η 7 -C 7 H 7 )] (18, R = Ph, nBu, tBu) described by Whiteley and coworkers.…”

Magnetic perturbation of the redox potentials of localized and delocalized mixed-valence complexes

“…The detailed synthesis and the properties of these compounds have already been presented elsewhere [43][44][45][46][47][48][49][50][51][52][53][54]. The oneelectron oxidized complexes present a mixed-valence character and as monoradicals they are paramagnetic.…”

Metall‐Alkinyl‐σ‐Komplexe: Synthesen und Materialien

“…Zur Untersuchung der Elektronenleitung zwischen verbrückten Übergangsmetallzentren wurde häufig auf konjugierte, Alkinyl-verbrückte Cp*Fe(dppe)-Einheiten zurück-gegriffen. [23,[170][171][172][173][174][175] [178] Der Einfluss der Länge der konjugierten Brücke wurde anhand von Verbindungen vom Typ [Fp*-(C C) n -Fp*] (n = 1-4, 6; Fp* = h 5 -(C 5 Me 5 )Fe(CO) 2 ) untersucht. [179,180] Die oligomeren Komplexe wurden durch Cu-katalysierte oxidative Kupplung hergestellt.…”