The First Coordination Polymers Based on 1,3‐Diphosphaferrocenes and 1,1′,2,3′,4‐Pentaphosphaferrocenes

Abstract

Phosphaferrocenes in combination with coinage metal salts proved to be excellent building blocks in supramolecular chemistry for the buildup of oligomeric and polymeric assemblies. The synthesis of a series of novel phosphaferrocenes containing the 1,3‐P2C3 iPr3 and/or the 1,2,4‐P3C2 iPr2 ligand is described herein. The self‐assembly processes of the 1,3‐diphospha‐, 1,2,4‐triphospha‐, and 1,1′,2,3′,4‐pentaphosphaferrocenes with CuI halides led to the formation of 1D or 2D polymers. With [Cp*Fe(η5‐P2C3 iPr3)] (Cp* = η5‐C5Me5), infinite chains are formed, whereas with [(η5‐P3C2 iPr2)Fe(η5‐P2C3 iPr3)] 1D ladderlike structures are obtained. These are the first polymers containing such a di‐ and pentaphosphaferrocene, respectively. On the other hand, the use of [Cp*Fe(η5‐P3C2 iPr2)] leads to the construction of 2D networks with intact sandwich complexes, which is uncommon for this class of complexes.

Why is Ferrocene so Exceptional?

“…Carbon atoms in one ferrocene ring can also be replaced by heteroatoms, although access does not involve ferrocene. For instance the piano‐stool complex [Fe(η 5 ‐C 5 H 5 )(CO) 2 (η 1 ‐pyrrole)] is used as a precursor for the synthesis of azaferrocene, [Fe(η 5 ‐C 5 H 5 )(η 5 ‐C 4 H 4 N)], whereas pentaphosphaferrocene, [Fe(η 5 ‐C 5 Me 5 )(η 5 ‐P 5 )], was synthesized by a related strategy that has been extended to a large variety of sandwich‐type complexes containing the CpFe fragment and to their supramolecular applications …”

Examination of Indium Triphospholyls as Precursors for Nanoparticle Synthesis

“…SI). In comparison, all previously reported derivatives (1,2,4‐P 3 C 2 R 2 ) − reveal a doublet and a triplet with similar coupling constants, except for (1,2,4‐P 3 C 2 i Pr 2 ) − which shows a higher order AB 2 pattern [17] . The yields and NMR chemical shifts of these derivatives are given in Table 1.…”

“…Over the last two decades, the use of triphospholyl as ligand has become more widespread because of the strong similarities between the polyphospholyl anions and their much more widely studied cyclopentadienyl analogues [15] . So far, the 1,2,4‐triphospholyl anions (1,2,4‐P 3 C 2 R 2 ) − with R=tert‐butyl ( t Bu), [16] isopropyl ( i Pr), [17] mesityl (Mes), [18] trimethylsilyl [19] and phenyl (Ph) [20] were reported. We present the synthesis of the new 1,2,4‐triphospholyl salts with sec‐butyl ( s Bu) and adamantyl (Ad) substituents.…”

“…In the 31 P{ 1 H} NMR spectra of the reaction mixture, a sharp singlet at 175.1 ppm was observed, which could be assigned to K(1,3‐P 2 C 3 Mes 3 ). In comparison, the signal for K(1,3‐P 2 C 3 i Pr 3 ) appears at 159.6 ppm [17] . Since it was not possible to separate the two compounds, the mixture of the diphospholyl and the triphospholyl salts was further reacted with InI.…”