1,1′-Di(heteroatom)-functionalised ferrocenes as [N,N], [O,O] and [S,S] chelate ligands in transition metal chemistry

Abstract

Dppf is one of the most useful and popular ligands in coordination chemistry. Its overwhelming success has overshadowed and arguably even delayed the development and use of closely related ferrocene-based ligands with two ligating N, O or S atoms. Recently, however, dynamic progress concerning such homo-donor ligands can be noted. This tutorial review describes the main results obtained over the past decade in order to introduce the reader to an exciting field which currently shows particularly rapid development. The material is organised in sections according to ligand type, followed by a section which summarises the applications reported so far.

Mercury binding by ferrocenoyl peptides with sulfur-containing side chains: Electrochemical, spectroscopic and structural studies

“…Complexation of such systems with a cation usually causes a positive shift in the Fe(II)/Fe(III) redox potential, because the positive charge on the adjacent ion inhibits oxidation of the iron centre [14,16]. Upon addition of Hg(II) (as a solution of Hg(NO 3 ) 2 in acetonitrile), the redox potentials of ferrocenoyl peptides 1, 2, 3, 5 and 6 shift to higher potential, with the extent of the shift dependent on the concentration of mercury in the system ( Fig.…”

“…Ferrocene derivatives have been extensively utilised to study the interactions of chemical hosts with metal ions and other substrates, exploiting the electrochemical properties of the Fe(II)/ Fe(III) redox couple [14][15][16][17][18]. The highly reproducible redox behaviour of the ferrocene/ferrocenium redox system enables a range of electrochemical methods, with cyclic voltammetry (CV) most commonly employed [14,16].…”

“…The highly reproducible redox behaviour of the ferrocene/ferrocenium redox system enables a range of electrochemical methods, with cyclic voltammetry (CV) most commonly employed [14,16].…”

Dynamic behaviour of 1,n′-disubstituted ferrocenes

“…Unsymmetrical 1,n 0 -disubstituted ferrocenes [1,2] are useful building blocks for directional oligomers with ferrocene in the main chain or as starting materials for (chiral) ferrocene-containing chelating ligands potentially applicable in (asymmetric) catalysis [3][4][5][6][7][8][9][10][11][12][13][14][15].…”

Diaminocarbene[3]ferrocenophanes and Their Transition‐Metal Complexes

“…[3] We envisioned that it would be possible to create a new class of carbene-based ligands with relatively wide N-C-N angles and redox-switchable functions [4] by linking diaminocarbenes to 1,1'-disubstituted metallocenes. [5] In view of the affinity of carbenes for transition metals, the use of such ligands may lead to new redox-active complexes with tunable electronic properties. Herein, we describe a novel carbene architecture that contains a 1,1'-disubstituted ferrocene moiety and demonstrate its ability to engage in unique electronic interactions with coordinated transition metals.…”