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Phosphorus dendrimers (dendrimers having one phosphorus atom at each branching point) possess versatile properties, depending on the type of their terminal functions. This perspective article focusses on the synthesis and study of properties of phosphorus dendrimers functionalised on their surface by nitrogen ligands and their complexes. It is organized depending on the type of N-ligands (P,N ligands, N,N ligands, and N,N,N-ligands). Most properties concern catalysis, with palladium, copper, and scandium complexes. Recent advances concern anti-cancer properties, with dendrimers functionalised by copper and gold complexes of N,N-ligands. [ABSTRACT FROM AUTHOR]

In spite of the numerous possible applications of thiazoles as ligands for catalysis and as active molecules in medicinal chemistry, only a few studies have dealt with their versatile chemistry. Several selective modifications of the structure of these derivatives and mainly of thiazoyl phosphines are detailed, thus illustrating the great possibilities to tailor at will their structures and therefore their properties. The formation of Ru and Au complexes is reported. Six of these new thiazoyl phosphines were characterized by X-ray crystallography as well as two of their gold complexes. [ABSTRACT FROM AUTHOR]

Dendrimers are hyperbranched and monodisperse macromolecules, generally considered as a special class of polymers, but synthesized step-by-step. Most dendrimers have a uniform structure, with a single type of terminal function. However, it is often desirable to have at least two different functional groups. This review will discuss the case of bifunctional phosphorus-containing dendrimers, and the consequences for their properties. Besides the terminal functions, dendritic structures may have also a function at the core, or linked off-center to the core, or at the core of dendrons (dendritic wedges). Association of two dendrons having different terminal functions leads to Janus dendrimers (two faces). The internal structure can also possess functional groups on one layer, or linked to one layer, or on several layers. Finally, there are several ways to have two types of terminal functions, besides the case of Janus dendrimers: either each terminal function bears two functions sequentially, or two different functions are linked to each terminal branching point. Examples of each type of structure will be given in this review, as well as practical uses of such sophisticated structures in the fields of fluorescence, catalysis, nanomaterials and biology. [ABSTRACT FROM AUTHOR]

The use of dendrimers as soluble supports of catalytic entities offers efficient tools for 'greener' catalysis. Indeed, thanks to their large size, dendrimers can be recovered and reused; depending on their structure, they can be tolerant to aqueous media or even soluble in water; and they can be used as ligands of cheap metals such as copper. We describe several examples of dendritic catalysts having such properties, based on the functionalization of phosphorus-containing dendrimers. [ABSTRACT FROM AUTHOR]

Abstract: This review concerns metallic groups linked to the internal structure (core or branches) of phosphorus-containing dendrimers that are dendrimers possessing one phosphorus at each branching point. The synthetic aspect will be described first, ranked depending on the precise location of the metal: either at the core, or throughout the structure, or at one or several specific layers (layer-block type dendrimers), or in selected branches (segment-block type dendrimers). The second part concerns the properties of these metallo-phosphorus dendrimers, with emphasis on the information afforded by the metallic centers about the internal structure, and on the influence of the “burying” of a function inside a dendrimer on the properties of this function. The last part concerns the applications of some of these metallodendrimers in catalysis. [Copyright &y& Elsevier]

Abstract: Catalytic amounts of cheap, non-toxic, easy-to-handle and non-sensitive sodium tert-butoxide are able to promote the dehydrogenative oxidation of a wide array of secondary alcohols using inexpensive benzophenone as the H-acceptor. The corresponding ketones, highly important intermediates and targets throughout life and material sciences, are very selectively obtained under mild conditions. [Copyright &y& Elsevier]

[Display omitted] • Phosphorus dendrimers have been functionalized by a large variety of ligands suitable for the complexation of copper. • Copper complexes of phosphorus dendrimers are efficient catalysts in a range of reactions. • Copper complexes of phosphorus dendrimers can be efficiently recovered and reused. Phosphorus dendrimers are highly branched macromolecules, built with one phosphorus atom at each branching point. These dendrimers can be functionalized at will on the terminal functions. Grafting as terminal functions ligands suitable for the complexation of copper has been carried out several times, in particular with the aim of using the corresponding complexes as catalysts in a range of reactions, from O- and N -arylations and -vinylations, to the asymmetric benzoylation of linear or cyclic diols. A sequel of this work concerns the study of anticancer activity of analogous dendritic copper complexes. [ABSTRACT FROM AUTHOR]

Dendrimers are hyperbranched macromolecules having a perfectly defined and multifunctionalized structure, constituted of branches emanating radially from a central core. The structure of dendrimers is particularly modular, and can incorporate in different parts coordination complexes. In this review, we will present the interplay between dendrimers and coordination chemistry in three main fields: catalysis, materials, and biology. Most of the examples will be taken from the work done with phosphorus-containing dendrimers, but the pioneering work carried out with other dendrimers will be also presented. One of the major improvements that metallodendrimers have afforded concerning catalysis is their easy recovery and reuse, bridging the gap between homogeneous and heterogeneous catalysis. Another major improvement concerns the “dendritic effect” which can afford impressive outcomes concerning the increase of yield and of enantioselectivity, together with a decrease of the leaching of metals, and consequently of waste. Dendrimers can be used also for the synthesis and stabilization of metallic nanoparticles, for the modification of metallic surfaces at the nanometric scale, and for the synthesis of mesoscopically ordered hybrid materials. Finally metallodendrimers have high potency against cancerous cell lines, and they appear to operate via a different mechanism of action compared with native metallodrugs, opening new avenues for the search of improved anti-cancer agents. [ABSTRACT FROM AUTHOR]

Highlights: [•] Phosphorhydrazone dendrimers incorporate various ligands in various locations. [•] Phosphorhydrazone metallodendrimers are versatile, efficient, recyclable catalysts. [•] Some phosphorhydrazone metallodendrimers are usable in the field of materials. [•] Some metallodendrimers have anti-proliferative properties against cancerous cells. [ABSTRACT FROM AUTHOR]

Abstract: We report the synthesis of a dense dendrimer ended by the PTA ligand (1,3,5-triaza-7-phosphaadamantane), and the use of the corresponding Rh and Ru complexes for catalysis. The catalytic properties of these dendrimers are compared with those of two other dendrimers: a dendrimer of the same generation but having half the number of ligands, and a dendrimer of the next generation, but having the same number of ligands. The positive influence of the density of catalytic sites on the surface of these dendrimers for alcohol isomerization in water has been evidenced. [Copyright &y& Elsevier]

Various methods of synthesis of phosphorus dendrimers are presented, in particular a fast method which allows creating each generation in only one step, while multiplying by 5 the number of end-groups. These methods of synthesis can easily be modified to place selectively on the surface, inside, within the branches or at the core, functional groups chosen according to the properties or the applications which they can bring. In many cases, the size of the dendrimer (its generation) has an influence on these properties. Various applications in the fields of catalysis, materials, and biology are presented. To cite this article: Anne-Marie Caminade et al., C. R. Chimie 6 (2003). [Copyright &y& Elsevier]

Review: 61 refs. [ABSTRACT FROM AUTHOR]