Ferrocene‐ and Biferrocene‐Containing Macrocycles towards Single‐Molecule Electronics

Abstract

Cyclic multiredox centered systems are currently of great interest, with new compounds being reported and developments made in understanding their behavior. Efficient, elegant, and high‐yielding (for macrocyclic species) synthetic routes to two novel alkynyl‐conjugated multiple ferrocene‐ and biferrocene‐containing cyclic compounds are presented. The electronic interactions between the individual ferrocene units have been investigated through electrochemistry, spectroelectrochemistry, density functional theory (DFT), and crystallography to understand the effect of cyclization on the electronic properties and structure.

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

“…In this field, ferrocene constitutes a candidate of choice by its facile oxidation and the reversibility of the oxi dation process. As a result of this, an efficient regeneration of the neutral form can be ensured, and it thus offers unique opportunities to create and suppress "on demand" absorption bands such as charge transfer (CT) or intervalence charge transfer (IVCT) bands at low energy by simply modifying the oxidation state of the metal center [24]. From this point of view, ferrocene is an unrivalled building block for the design of push-pull structures.…”

Haloferrocenes: Syntheses and Selected Reactions

“…1,1′-Diiodoferrocene (44) afforded 1,1′-bis(trifluorovinyl)ferrocene (166) in an excellent 97% yield via Negishi coupling with (trifluorovinyl)zinc chloride (Scheme 54 Sonogashira coupling reactions have frequently been used for the synthesis of alkynylferrocenes. 34,49,[104][105][106][107][108][109][110][111][112][113][114][115][116][117][118][119][120][121][122] As the presentation of all of these would exceed the scope of this review, the discussion is restricted to some representative or particularly interesting examples.…”

“…Subsequent ring closure with copper(I) thiophene-2-carboxylate gave macrocycle 185 in 25% yield (Scheme 60). 106 Scheme 60 Multiple Sonogashira couplings in the synthesis of ferrocene-based macrocycles; DIPA = diisopropylamine, NMP = N-methylpyrrolidone 106…”

Fulvalene as a platform for the synthesis of a dimetallic dysprosocenium single-molecule magnet

“… 34 Dinucleating fulvalenyl ligands have been used extensively in transition metal sandwich chemistry, 35 with recent examples including macrocyclic poly(ferrocenyl) compounds with potential applications as molecular electronic materials. 36 , 37 In contrast, the use of such ligands in f-element chemistry is uncommon, and in the case of the lanthanides was, hitherto, limited to the dimetallic divalent compounds [M(THF)(η 5 :η 5 -Fv tttt )] 2 with M = Sm, Eu or Yb. 38 …”