Synthesis and Electrochemical Behavior of Ferrocenyl‐Functionalized Metallocenes M(η⁵‐C₅H₅)₂(EFc)₂ (M = Ti, Zr; E = O, S, Se)

Abstract

Metallocenes [Ti](Cl)(OFc) (4) and [M](EFc) 2 {[M] = M(η 5 -C 5 H 5 ) 2 ; M = Ti: 5a, E = O; 5b, E = S; 5c, E = Se. M = Zr: 6, E = O; Fc = Fe(η 5 -C 5 H 4 )(η 5 -C 5 H 5 )} were prepared by the treatment of [M]Cl 2 (1, M = Ti; 2, M = Zr) with FcOLi (3), or by the reaction of FcELi (8a, E = S; 8b, E = Se) with 1. The solid-state structures of the metallocenes 4, 5a,b, and 6 are reported. The electrochemical (4, 5a,b,c) and spectroelectrochemical (in situ UV/Vis/NIR) [5a, Fc 2 E 2 for comparison; E = S (9), Se (10)] behavior is discussed. All Ti compounds show irreversible Ti IV /Ti III reduction processes at E pc = -1520 to -2100 mV. Reversible Fc [a]

Influence of Rare-Earth Ion Radius on Metal–Metal Charge Transfer in Trinuclear Mixed-Valent Complexes

“…For [1] + , the region of the structure adjacent to the Fe­(III) center exhibits bond elongation in the pyrrole ring (N1-C02) and imine (C03-N2), while the Fe­(II) side shows bond contraction (N1–C22, and C23–N3) compared to the unoxidized ligand 1 . The Cp–Cp distances (computed between the centroids of the Cp rings) are typical for ferrocene compounds and commensurate with oxidation to ferrocenium, as we observe an elongation of this distance. − We emphasize that oxidation state assignments are formal assignments based on a predominantly localized structure.…”

Ferrocene: An unrivaled electroactive building block for the design of push-pull dyes with near-infrared and infrared absorptions

“…To improve their stability, an effective strategy consists in introducing heteroatoms such as oxygen, selenium or sulfur [168][169][170][171][172][173][174]. On this basis, a series of Zr and Ti-based metallocenes bearing ferrocene substitutes were examined for the spectroelectrochemical properties [175]. Metallocenes M32 and M33 could be prepared using the same methodology, by first generating the ferrocenyloxy lithium salt and by carrying out the nucleophilic substitution at low temperature with 2.2 equivalents of ferrocenyloxy lithium.…”

Syntheses, Characterization, and Redox Activity of Ferrocene-Containing Titanium Complexes

“…The synthesis and applications of heterobimetallic complexes are an ever-present topic in inorganic chemistry. − Of particular interest is the incorporation of ferrocene derivatives into other metal complex frameworks. − Since the discovery of ferrocene and its formerly unprecedented sandwich-structure, , many ferrocene derivatives have been reported. − Because of the manifold derivatization options of the ferrocene framework, there is a huge number of polymetallic complexes containing ferrocenes which are linked with different bridges (C; − N; − O; − P; S; , Se; , N,O ,, ). In the context of ferrocene-based titanium complexes, several studies have focused on clusters, − electron-deficient catalysts , and redox-active compounds. ,− Because the chemistry of bis­(π–η 5 :σ–η 1 -pentafulvene)titanium complexes is characterized by a broad range of E–H activation and Ti–C functionalization reactions, they are excellent precursors for the generation of bimetallic Ti/Fe complexes. , As we reported earlier, both monofunctional and bifunctional transformations are possible depending on the substrate.…”

“… 5 − 7 Since the discovery of ferrocene and its formerly unprecedented sandwich-structure, 8 , 9 many ferrocene derivatives have been reported. 10 − 13 Because of the manifold derivatization options of the ferrocene framework, there is a huge number of polymetallic complexes containing ferrocenes which are linked with different bridges (C; 14 − 17 N; 18 − 22 O; 23 − 25 P; 26 S; 27 , 28 Se; 29 , 30 N,O 28 , 31 , 32 ). In the context of ferrocene-based titanium complexes, several studies have focused on clusters, 33 − 36 electron-deficient catalysts 19 , 37 and redox-active compounds.…”