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The reaction under very mild conditions of the polyspirophosphazene copolymer with pendant diphenylphosphine groups {[NP(O2C12H8)]0.85[NP(OC6H4PPh2)2]0.15}n (I) (O2C12H8= 2,2’-dioxybiphenyl) with [Au(THT)Cl] (THT = tetrahydrothiophene) gives the neutral polymeric complex {[NP(O2C12H8)]0.85[NP(OC6H4PPh2-AuCl)2]0.15}n (II). The new material has been characterized by spectrocopic and thermochemical methods (TGA and DSC). Pyrolysis of the Au polymer (I) in air at 800 °C gave gold nanostructured materials that were characterized by TEM, SEM-EDAX and X-ray diffraction. Nanoparticles in the range of 90 to 130 nm were seen.

The reaction of [NPCl2]n first with 2,2'-dihydroxybiphenyl and K2CO3 or (R)-(+)-2,2'-dihydroxy-1,1'-binaphthyl and Cs2CO3, and subsequently with HO−C6H4−CO2Prn and Cs2CO3, gave the phosphazene copolymers {[NP(O2C12H8)]1-x[NP(O−C6H4−CO2Prn)2]x}n [x = 0.2 (1a), 0.35 (1b), 0.5 (1c), 0.7 (1d), and 0.85 (1e)] and the chiral analogues {[NP(O2C20H12)]1-x[NP(O−C6H4−CO2Prn)2]x}n [x = 0.2 (2a), 0.4 (2b), 0.45 (2c), 0.5 (2d), 0.55 (2e), 0.7 (2f), and 0.8(2g)]. The study of their properties as a function of the composition have revealed systematic changes in the electronic structure of the macromolecules, in the interplanar distances of their mesophases and in glass transition temperatures. The latter variation has demonstrated the strictly alternating nature of the copolymeric structures in the series 1 and 2. This is an experimental evidence supporting that the substitution of Cl in the [NPCl2]n with the bifunctional reagents or 2,2'-dihydroxybiphenyl and (R)-(+)-2,2'-dihydroxy-1,1'-binaphthyl as promoted by alkali...

The reactions of the spirocyclic phosphazene [N 3 P 3 (O 2 C 12 H 8 ) 2 Cl 2 ] (O 2 C 12 H 8 = 2,2'-dioxybiphenyl) with the thiophenols HS--C 6 H 4 --R and M 2 CO 3 (M = K or Cs) in refluxing acetone gave respectively the spirocyclic substituted derivatives [N 3 P 3 (O 2 C 12 H 8 ) 2 (SC 6 H 4 --R) 2 ] R = H ( 2a ), Br ( 2b ), OMe ( 2c ), NO 2 ( 2d ). The reaction is a two-step process the second of which is much faster than the first and the monosubstituted intermediate [N 3 P 3 (O 2 C 12 H 8 ) 2 (SC 6 H 4 --R)Cl] cannot be detected. By contrast, in the analogous reactions with the phenols HO--C 6 H 4 --R and M 2 CO 3 (M = K or Cs) in acetone or THF, to give the known derivatives [N 3 P 3 (O 2 C 12 H 8 ) 2 (OC 6 H 4 --R) 2 ], the first step is faster although both are very dependent on R, M and the solvent. Thus, in the case of the phenol HO--C 6 H 4 --OMe the reaction conditions could be adjusted to give the useful synthetic intermediate monosubstituted derivative [N 3 P 3 (O 2 C 12 H 8 ) 2 (OC 6 H 4 --...

Planar optical waveguides of some novel phosphazene inorganic polymers with high glass transition temperatures, T g > 150° C, have been prepared by spin-coating on glass and quartz substrates. Thicknesses between 0.5 and 2 μm and index steps of about An ∼0.2 (for quartz) and An ∼0.1 (for glass) at λ = 0.633 μm have been achieved. From one to five modes have been observed at wavelengths ranging from the green to the near infrared. Refractive indices have been well fitted to a Sellmeier dispersion equation. Waveguide losses are estimated to be around 10 dB/cm.

The vibrational spectra of three cyclic phosphazene molecules, [N3P3Cl4(O2C12H8)] (CP1), [N3P3Cl2(O2C12H8)2] (CP2) and [N3P3(O2C12H8)3] (CP3), are reported. The far-infrared, infrared and Raman spectra were recorded. The assignment of fundamental vibrational modes is assisted by quantum chemical computations of wavenumbers and Raman and infrared intensities. Fundamental vibrational modes characterized by wavenumber and intensity are identified in the infrared and Raman spectra of the series. Copyright © 1999 John Wiley & Sons, Ltd.

The direct reaction of [NPCl2]n with the difunctional reagent 2,2‘-dihydroxybiphenyl (HOC6H4C6H4OH) and K2CO3 in tetrahydrofuran gave soluble linear phosphazene high polymers instead of the expected cross-linked products. The reaction of [N3P3Cl6] with 1, 2, or 3 equiv of HOC6H4C6H4OH and K2CO3 in acetone gave the known spiro derivatives [N3P3Cl4(O2C12H8)], [N3P3Cl2(O2C12H8)2], and [N3P3(O2C12H8)3] without formation of bridging products, and the dichloro derivative reacted directly with para-substituted phenols HOC6H4R and K2CO3 in acetone to give the new compounds [N3P3(OC6H4R)2(O2C12H8)2] (R = Br, COC6H5, or OCH3), without signs of replacement of the bis(aryloxy) substituents. In an analogous manner, poly(dichlorophosphazene) [NPCl2]n reacted with HOC6H4C6H4OH and K2CO3 in THF without significant cross-linking to give, depending on the mole ratio, the soluble polymer [NP(O2C12H8)]n (Mw = 450 000, Tg = 160 °C) or the partially substituted polymers {[NP(O2C12H8)]0.35[NPCl2]0.65}n. The latter were subseque...

The phosphazene copolymers {[NP(O 2 C 12 H 8 )] 0.5 [NP(O–C 6 H 4 –CO 2 Pr n )(O–C 6 H 4 –L)] 0.5 } n [L = CN ( 1 ), PPh 2 ( 2 )] and {[NP(O 2 C 12 H 8 )] 0.6 [NP(O–C 6 H 4 –CO 2 Pr n )(O–C 5 H 4 N)] 0.4 } n ( 3 ) have been synthesized by sequential substitution from [NPCl 2 ] n . Their reactions with [W(MeOH)(CO) 5 ] gives the corresponding tungsten carbonyl complexes {[NP(O 2 C 12 H 8 )] 0.5 [NP(O–C 6 H 4 –CO 2 Pr n )(O–C 6 H 4 –CN)(W(CO) 5 ) 0.4 ] 0.5 } n ( 4 ), {[NP(O 2 C 12 H 8 )] 0.5 [NP(O-C 6 H 4 –CO 2 Pr n )(O–C 6 H 4 –PPh 2 )(W(CO) 5 ) 0.7 ] 0.5 } n ( 5 ), {[NP(O 2 C 12 H 8 )] 0.6 [NP(O–C 6 H 4 –CO 2 Pr n )(O–C 5 H 4 N–W(CO) 5 )] 0.4 } n ( 6a ), and {[NP(O 2 C 12 H 8 )] 0.6 [NP(O–C 6 H 4 –CO 2 Pr n )(O–C 5 H 4 N)(W(CO) 5 ) 0.4 ] 0.4 } n ( 6b ), that have been fully characterized by IR and NMR spectroscopies. The thermal properties (TGA and DSC) of the polymeric complexes showed that they are high glass transition materials that undergo a complete decarbonylation below 300 °C forming metal containing species that have a stabilizing effect on the polymeric matrices. The final residues up to 800 °C are of the order of30–50%.

The high molecular weight phosphazene random copolymer {[NP(OC6H5)2]0.94 [NP(OC6H5)(OC6H4CNFe(dppe)Cp)]0.06[PF6]0.06}n (1), that carries [Fe(dppe)Cp] cationic fragments coordinated to nitrile side groups, has been synthesized from the copolymer {[NP(OC6H5)2]0.94[NP(OC6H5)(OC6H4CN)]0.06}n and the complex [Fe(CH3CN)(dppe)Cp][PF6] by the complete elimination of the acetonitrile from the equilibrium mixture that they form in dichloromethane solution. The new polymer has been fully characterized by a detailed discussion of the IR and NMR data that may be also useful for the study of other polymeric complexes with similar metal fragments. The cyclic voltammogram of (1) showed an oxidation process that is chemically irreversible but, rather unexpectedly, electrochemically reversible. All the results were interpreted by comparison with the data obtained for the new cyclic model complexes {N3P3(OC6H4-R)5[OC6H4CNFe(dppe)Cp]}[PF6] R=H (2a), Bu t (2b), (see chart 1) that were synthesized by a similar method using the nitrile phosphazene ligands [N3P3(OC6H4-R)5(OC6H4CN)]

The reaction of [NPCl2]n with substoichiometric amounts of the thiophenols HS—C6H4—R (R = H, Br) and Cs2CO3 in THF at room temperature, gave solutions of {[NPCl2]1-x[NP(S—C6H4—R)2]x}n [R = H (1a), Br (1b)]. The reaction of the derivative with R = Br and x = 0.3 with HO—C6H4—Br gave the random copolymer {[NP(O—C6H4—Br)2]0.7 [NP(S—C6H4—Br)2]0.3}n (2); similarly, the reaction of 1 with the biphenol HO—C6H4—C6H4—OH gave the random copolymers {[NP(O2C12-H8)]0.75[NP(S—C6H4—R)2]0.25}n [R = H, (3a); R = Br, (3b)] as soluble and stable white solids., We thank the Spanish Dirección General de Investigación Científica y Técnica (DGYCYT), Project PB97-1276, for support.