Container dendrimers

Divergent Approaches to Phosphorus-Containing Dendrimers and their Functionalization J.-P. Majoral, A.-M. Caminade... 

Electrochemical and Photochemical Properties of Metal-Containing Dendrimers... 

All the fullerene-containing dendrimers reported to date have been prepared with a Cgo core but never with fullerene units at their surface or with Cgg spheres in the dendritic branches. We have recently started a research program on the synthesis of dendrons substituted with fullerene moieties. These fulleroden-drons are interesting building blocks for the preparation of monodisperse fullerene-rich macromolecules. In addition, they are also amphiphilic compounds capable of forming stable Langmuir films at the air-water interface. 

Divergent Approaches to Phosphorus-Containing Dendrimers and their Functionalization... 

Although the first publication on dendrimers appeared in 1978 [ 1 ] it is only in 1990 that the first report on phosphorus-containing dendrimers was published [2] i.e. after numerous papers devoted to the synthesis of organic dendrimers and practically at the same time than the description of a silicon containing dendrimer. 

The aim of this review is to present the state-of-the-art concerning the synthesis and the chemical properties of phosphorus-containing dendrimers with emphasis made on the specificity introduced by phosphorus. 

Most of the methods of synthesis reported above present some limitations and constraints lack of solubility for polycationic phosphorus-containing dendrimers from generation 3 [2], dendrimers of weak molecular weight [4], difficulties to overcome cross Unking reactions [6], possibility only to incorporate phosphorus groups on the surface of dendrimers [3], etc. 

Even if only a few methods of synthesis of phosphorus-containing dendrimers are reported up to date, it is clear that these macromolecules now constitute a well known class of polymers whose studies appear to be an emerging field of research. 

Even if attention has not been focussed on the physical properties of phosphorus-containing dendrimers in this review, one can mention the high dipole moment values observed for these polymers up to 328 debyes for generation 11. 

In summary, phosphorus-containing dendrimers have their own specificity applications of these derivatives in different areas would be numerous in the near future. Some of these applications are in progress. 

From a structural viewpoint, most of the metal-containing dendrimers can be classified according to the following four categories ... 

Fig. la-d. Different kinds of metal-containing dendrimers a a metal complex as a core b metal complexes only as peripheral units c metal complexes only in the branches d metals as branching centers... 

There are, of course, metal-containing dendrimers that belong to more than one of the above-mentioned categories. Examples are the heptametallic dendrimer made of a central Fe(Cp)(C6Me6)+ core and coated with 6 ferrocene moieties [ 12], and the heterometallic dendrimers made of an organic core, containing up to 6 Pt(IV)-based organometallic species in the branches, and coated with up to 12 ferrocene units [13]. 

This review of the electroactive metal-containing dendrimers, not exhaustive for space reasons, clearly indicates that several interesting dendrimers have been synthesized, but in most cases their electrochemical properties have not been investigated in detail. A few carefully performed studies have shown that electrochemistry is a powerful technique (i) to elucidate the structure (and purity) of the dendrimers, a task not at all easy in the case of highly charged compounds,... 

Many other metal-containing dendrimers which are potentially interesting from a photochemical viewpoint [43,69] have been synthesized, but their photochemical and photophysical properties have not yet been investigated. 

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