Cyclotriphosphazene, dendrimers

Fig. 2 Fixation of chiral Josiphos ligands to a first-generation dendrimer containing a cyclotriphosphazene core...

The synthetic and spectral details to the P-dendrimers up through the third generation from a cyclotriphosphazene core (N3P3(OC6H4CHO)6) 116,1171 possessing six formyl moieties have also recently been reported. 118 The simple procedures lead to a spherical surface with electrophilic or nucleophilic reactive moieties, such as aldehydes, hydrazones, and aminophosphines. 

N3P3F6 n(OAr)n and their application as stabilizing agents in LiPFe-contain-ing batteries has been patented. The compound [NP(OMe)2]3 has also been used as stabilizer in lithium-ion batteries.Cyclotriphosphazenes having phenoxy and UV-absorbing groups have been patented. Immobilization of dendrimers based on a cyclotriphosphazene core has been covered. ... 

Thus, supermolecular liquid crystals with a cyclotriphosphazene dendritic core and polycatenar mesogenic units (144) were obtained in three steps by the conventional sequence of substitution (i), derivatization (ii and iii) methods from [N3P3CI6] (Scheme 9). Due to the microsegregation of the alkyl chains and the aromatic central cores and the space-filling properties, compounds (144) adopt a discotic conformation assembled in a columnar mesophase and illustrate the possibilities of using cyclotriphosphazenes for the design of columnar assemblies at room temperature, in the mesophase or in a vitrified solid state with interest for applications in material science. Similarly, the new family of solution processable, photoluminescent, monodisperse nanocomposite dendrimers (145) (Tg > 165 °C, > 465 °C)... 

Phosphazene chemistry is covered separately elsewhere within this volume but three notable papers involving theoretical and computational chemistry methods have been reported. Non-empirical RHF/6-31G and MP2/6-31G quantum chemical methods have been used to calculate the molecular structure of two trichlorophosphazenes (8) and (9). The corresponding geometric parameters obtained from the calculations were compared with XRD analysis data previously reported in the literature. Conformational differences between the two molecules, previously found by XRD analysis of the crystals, were confirmed by non-empirical quantum chemical calculations on the molecules in the free state and the features of their geometry were discussed. A DFT study of the structural organization and infrared spectra of hexakis 4-iV -dichloro(thio)phosphonyl-A -methyl-dia-zobenzene cyclotriphosphazene, a phosphorus-containing dendrimer built... 

Ferrocene has also been encapsulated inside a symmetric ether-amide shell—the synthesis again begins with the use of l,l -bis(chlorocarbonyl)ferrocene at the core/ and these dendrimers have been examined in relation to their anion-binding ability. " Ferrocene dendrimers have also been prepared with cyclotriphosphazene cores/ trisub-stituted benzene cores/ and oligo-alkylamine cores. Ferrocene has been used as the central subunit in a number of dendritic structures such as the series of dendrimers shown as 20 again, the initial synthesis begins with chlorocarbonylferrocene. It has also been used in many cases as the peripheral group on molecules such as those shown in... 

Cyclotriphosphazene core. Tetrahedron Lett., 44, 7281-7284. (j) Poniatowska, E., and Salamon czyk, G. M. (2003). Phosphite Dendrimers and their Organometallic Derivatives. Tetrahedron Lett., 44, 4315-4317. (k) Angmell, L Muller, G. Rocamora, M. Rossell, 0., and Seco, M. (2003). Synthesis and Catalytic Properties of Neutral and Cationic Rhodium- and Iridium-Containing Carbosilane Dendrimers. Dalton Trans.,... 

Another interesting application of dendrimer-like cyclophosphazene derivatives, involved the formulation of docataxel by micelle-encapsulation using a tripodal cyclotriphosphazene amphiphile, [NP(MPEG750)(GlyPheLeu)2Et]3 (90). The latter apparently has better properties (significantly lower clearance rate) than the currently used derivatives. ... 

Dendrimers are macromolecular systems that can be grown from a central core structure. Cyclotriphosphazenes have served as a central core onto which... 

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