Coordination and organometallic chemistry of cyclophosphazenes and polyphosphazenes

Abstract

This review describes the chemistry of cyclophosphazene and poiyphosphazene iigand systems and their transition and organometallic complexes. The structures of the ligands and the complexes are discussed.

Organometallic Derivatives of Cyclotriphosphazene as Precursors of Nanostructured Metallic Materials: A New Solid State Method

“…Although a considerable number of cyclotriphosphazenes are known [27][28][29][30][31][32][33][34][35][36] those of Ti [36] are relatively scarce.…”

Competitive formation of spiro and ansa derivatives in the reactions of tetrafluorobutane-1,4-diol with hexachlorocyclotriphosphazene: A comparison with butane-1,4-diol

“…The 1 H NMR spectra of the spiro compounds, (3), (5) and (8), are complex multiplets with similar chemical shifts (Table 1), whereas those for the mono-ansa moieties in compounds (4) and (6) are observed as two complex multiplets and for the non-gem cis bis-ansa compound (7) as four complex multiplets. Although analysis of these multiplets, in principle, could lead to 3 J(FH) and 3 J(PH) magnitudes and a conformational analysis of the spiro and ansa rings, in practice, this is not feasible because the appropriate Karplus-type relations for 3 J(FH) and 3 J(PH) magnitudes in such cyclophosphazene derivatives are not known.…”

“…Bridged compounds became important for reactions of (1) with di-amines of increasing chain length (n = 4, 5) [3] and with chain lengths n >5 only bridged compounds were reported by Guerch et al [4]. On the other hand, only ansa derivatives were obtained with structurally rigid di-functional reagents such as the di-lithium derivatives of ferrocene, ruthenocene and dibenzylchromium [5][6][7][8]. Herberhold and co-workers [9] reported that the reactions of the Li salt of the ferrocene (fc) diol with cyclophosphazenes, (1) and N 3 P 3 F 6 (9), gave ansa derivatives, but only spiro-derivatives were obtained when the Li salts of the di-thiol or di-selenol ferrocene were used as reagents, in spite of the larger linking atoms.…”

“…Similarly, the chemical shifts of the >P(OR)Cl group of the ansa derivatives move to high frequency (downfield) as the cyclophosphazene (4) is further substituted with spiro (6) or ansa (7) tetrafluorobutanedioxy moieties ( Table 1). Whilst the chemical shifts of the PCl 2 [for isomers (3) and (4)] and P(OR) 2 groups [for isomers (5), (6) and (7)] seem to be insensitive to the nature of the disposition of the P-Cl bonds (geminal or cis-non-geminal), the shifts of the P(OR)Cl group [for isomers (6) and (7)] show some differences. It is noteworthy that in these isomers the two P-Cl bonds of (7) represent the only example in this series, where these two bonds are in a trans-relationship.…”

Complexes With Biologically Active Ligands. Part 71 Synthesis andFungitoxic Activity of Metal Complexes Containing 1,3,5‐tris‐(8‐Hydroxyquinolino)‐ Trichlorocyclo‐Triphosphazatriene

“…[2][3][4][5][6] The cyclophosphazenes behave as poor donors towards metal ions, unless electron-releasing moieties, such as alkyl or amino, are present in their molecule. In contrast to the numerous well-characterised complexes of some amino-or alkyl-substituted cyclotetraphosphazenes, complexes of relatively basic cyclophosphazenes, possessing heterocyclic nitrogen base moieties in their molecule were less investigated.…”