Dendritic catalysis

After submission of this manuscript, the field of dendritic catalysis has further evolved. Some representative examples are given below. 

Ribaudo F, van Leeuwen PWNM, Reek JNH (2006) Supramolecular Dendritic Catalysis Noncovalent Catalyst Anchoring to Fimctionalized Dendrimers. 20 39-59 Richmond TG (1999) Metal Reagents for Activation and Functionalization of Carbon-Fluorine Bonds. 3 243-269... 

Already at an early stage in the research with dendritic catalysis, these novel systems were proposed to form a promising class of recyclable catalysts. Furthermore, new, interesting properties were proposed to arise by catalyst attachment to these large, structurally well-defined polymers. In the previous section we summarized the results obtained so far in the recycling of dendritic catalysts, and here we describe some of the dendritic effects observed in catalysis. Both negative and positive effects are discussed, in an attempt to provide a balanced view of the current state of affairs. 

Whether dendritic catalysis can compete successfully in commercial applications with other systems remains to be seen. Two-phase catalysis and catalysis by... 

The main emphasis has so far been placed on metal-containing catalysts, both in the field of dendritic catalysis and in organic catalysis in general. However, the current trend is increasingly towards catalysis with purely organic compounds. A number of example of such metal-free - and dendritic - catalysts,... 

Whether dendritic catalysis can compete successfully in commercial applications with other strategies that allow recycling of the catalyst remains to be seen. Dendrimer supports are still relatively expensive, but for applications that do not require the well-defined structure of the dendrimer support, hy-perbranched polymers can offer a cheaper alternative. A recent novel strategy in this research area that might provide the added value required to make the step towards commercial applications involves the noncovalent functionalization of dendritic support with catalysts (Fig. 1). This offers several advantages above the traditional covalent approaches. In this chapter we will review the progress in the area of supramolecular dendritic catalysis. 

Supramolecular Dendritic Catalysis Noncovalent Catalyst Anchoring to Functionalized Dendrimers... 

Another advantage of dendrimer-based catalysts concerns their easy recovery by stabilization at the surface of a polymer. The principal activities in dendritic catalysis lie in homogeneous catalysis, including Kharash addition of CC14 to methacrylate, palladium-catalyzed allylic alkylation, hydrogenation of olefins, hydroformylation, cyclopropanation, and oxidation.258 Dendrimers with redox-active cores have been proposed as promising materials for miniaturized information-storage circuits.259... 

Wang D, Astruc D. Dendritic catalysis basic concepts and recent trends. Coord Chem Rev 2013 257 2317-34. 

Dendritic catalysis have been used in various chemical reactions, including the Suzuki-Miyaura reaction, Mizoroki-Heck reaction, hydrogenation reaction, carbonylation and hydroformylation reactions, oxidation reaction, polymerization and oligomerization reactions, arylation reaction, alkylation reaction, and asymmetric synthesis [6]. Recently, dendritic catalysts have been reviewed by Astmc et al. [6], In another review article. Reek et al. reviewed the applications of dendrimers as support for recoverable catalysts and reagents [58]. The authors believed that catalytic performance in these systems depends on used dendritic architecture. 

Dendritic shells can be used to create a nanoenvironment favorable for catalysis, or to provide shielding for functional groups at the dendritic core. From various examples provided in this chapter, the utility of dendritic catalysis in various chemical reactions can be concluded. They have the potential to approach catalysts benefiting from high activity, high selectivity, high stability, and easy separation. 

Mery, D. and Astruc, D. (2006) Dendritic catalysis Major concepts and recent progress. Coordination Chemistry... 

Deng s group [54] first extended dendritic catalysis into asymmetric transfer hydrogenation. In their report, Noyori s excellent ligand (S,S)-TsDPEN was incorporated into the focal point of the Frechet-type dendrimer (26), and subsequently... 

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