Synthesis, Structure, and Properties of 1,1‘-Diamino- and 1,1‘-Diazidoferrocene

Abstract

We report an improved synthesis of 1,1′-diaminoferrocene, employing the reduction of 1,1′diazidoferrocene with H 2 -Pd/C, along with extensive characterization data for both compounds. Diaminoferrocene undergoes a reversible 1eoxidation in CH 3 CN at a potential of -602 mV vs Fc 0/+ , one of the most negative redox potentials for a ferrocene derivative. The chemical reversibility of this process was confirmed by isolation of the stable, 17-electron [Fc(NH 2 ) 2 ] + cation as PF 6 -, OTf -, and TCNEsalts. In the solid state, diaminoferrocene exists in two conformations: one with the NH 2 groups eclipsed, and the other with the NH 2 groups offset by one-fifth turn around the Cp-Fe-Cp axis. Diazidoferrocene, on the other hand, exhibits only the fully eclipsed conformation in the solid state. The Fe-Cp(centroid) vectors in the diazidoferrocene molecules are roughly aligned with the crystallographic c-axis, and the molecules form layers perpendicular to this axis. The compound is thermally unstable at elevated temperatures, and rapid heating above its melting point results in explosion.

Rare Earth Arene-Bridged Complexes Obtained by Reduction of Organometallic Precursors

“…In 2000, J. Arnold reported a reliable synthesis of 1,1′-diaminoferrocene (Shafir et al, 2000) and introduced the trimethylsilyl version fc(NHSiMe3)2 (H2(NN TMS )) to group 4 metals, titanium and zirconium, to afford metal dimethyl and dibenzyl complexes (NN TMS )TiMe2 and (NN TMS )ZrBn2 (Bn = CH2Ph) (Chart 3-1) .…”

A ferrocene-based catecholamide ligand: the consequences of ligand swivel for directed supramolecular self-assembly

“…1,1'-diaminoferrocene was prepared following a literature procedure [29]. All NMR spectra were recorded using either Bruker AV-500 or DRX-500 MHz spectrometers at the indicated frequencies.…”

1,3,2-Diazaphospha-[3]ferrocenophanes. Molecular Structures and Multinuclear Magnetic Resonance Studies

“…All other solvents were distilled from Na metal in an atmosphere of argon. 1,1 -Diaminoferrocene (1) was prepared according to the published procedure [12]. Triethylamine was distilled from Na prior to use.…”

“…In the case of cyclic Scheme 1. 1,1 -Diaminoferrocene [11,12] and four 1,3, 2-diazaphospha [3]ferrocenophanes reported in a preliminary study [13].…”

“…1,1 -Diaminoferrocene (1) [11,12] (Scheme 1) is a potentially useful starting material to prepare novel cyclic diaminophosphanes, since the 1,1 -ferrocenediyl group is bulky and may provide a fairly rigid backbone in 1,3,2-diazaphospha- [3]ferrocenophanes. In a preliminary report [13], we have disclosed the synthesis and molecular structures of 2a and 2d, and it was pointed out that the 2-phenyl derivative 3a may have a different structure as far as the mutual orientation of the P-C and the N-H bonds Table 1.…”