Solution Conformation and Self‐Assembly of Ferrocenyl(thio)ureas

Abstract

Conformations and (dis)assembly processes of ureas and thioureas are of fundamental importance in supramolecular chemistry, anion binding, or crystal engineering, both in solution and in the solid state. For sensing and switching processes a redox-active unit, such as the ferrocene/ferrocenium couple, is especially suitable. Here, self-assembly processes of redox-active ferrocenyl(thio)ureas FcNHC(X)NHR [X = O, R = Fc (1), Ph (2), 1-naphthyl (3), Me (4), Et (5); X = S, R = Fc (6), 1-

Protic Ferrocenyl Acyclic Diamino Carbene Gold(I) Complexes

“…On the other hand, the diaminocarbene complexes 2 Et2 and 2 iPr2 are oxidized reversibly to [2 Et2 ] + and [2 iPr2 ] + at 105 and 115 mV vs. ferrocene in CH 2 Cl 2 /[ n Bu 4 N][B(C 6 F 5 ) 4 ], respectively (Supporting Information, Figures S16-S19). These values are lower by 440-475 mV compared to that of the [1] + /1 and chlorido (ferrocenyl Fischer carbene) gold(I) redox couples, [41] but at typical potentials of N-substituted ferrocenes, [68] Nferrocenyl amides, thioamides, [72] ureas, thioureas [73] or chlorido Fc-MIC gold(I) complexes. [44] Consequently, the oxidation process is assigned to the ferrocene/ferrocenium redox couple, rather than an Au II/I couple.…”

N-Cobaltocenium Amide as Reactive Nucleophilic Reagent for Donor–Acceptor Bimetallocenes

“…As our group and others have a strong interest in the development of redox-active oligoferrocene amide foldamers, ferrocene-based redox switches involving classical NH···X and nonclassical NH···Fe hydrogen bonds, ferrocene amide ion sensors, amide-linked ferrocene-chromophore conju­gates, ,,, and redox-appended enzyme models, we became strongly interested in the employment of charged cobaltocenium Cc + building blocks in analogous isosteric systems. The positive charges in the parent systems and the expanded redox potential range toward more negative values are attractive assets in these applications. ,, The now good availability of [Cc-COOH] + already allowed us to devise a porphyrin-cobaltocenium dyad [P-NHCO-Cc + ].…”

A Ferrocenyl Amino Substituted Stannylene as an Intramolecular Fe→Sn Lewis Adduct

“…Our group and others have shown, that the electron‐rich, sterically demanding and redox‐active ferrocenyl moiety is able to form strong XH ··· Fe hydrogen bonds (X = O, N) . We suppose that ferrocene could act both as a Lewis base beyond this Brønstedt‐type basicity.…”