Homogeneous catalysis with phosphorus dendrimer complexes

Abstract

Dendrimers are highly branched macromolecules, which have properties in many different fields, in particular for catalysis. This review presents an exhaustive view about complexes of phosphoruscontaining dendrimers (having a phosphorus atom at each branching point), used as homogeneous catalysts in a range of reactions. First, catalysed reactions for CC bonds formation using Pd, Rh, Ru, or Sc complexes will be displayed; then formation of CO and C-N bonds using Cu complexes as catalysts will be shown. At the end, miscellaneous reactions catalysed without metal (organocatalysis) will be displayed. Despite their size, dendrimers are generally soluble in the reaction media, thus they afford homogeneous catalysts. However, their size is by far larger than the size of the reagents and products, thus they are generally easily separated, simply by adding a solvent in which the products are soluble, but not the dendrimers. The recovery and reuse of dendrimers (recycling) is an important advantage compared to classical monomeric catalysts, which will be emphasized in this review, together with the so-called dendrimer (or dendritic) effect, which is an enhancement of a property when the size of the dendrimer increases.

Functionalization of graphene oxide with a hybrid P, N ligand for immobilizing and stabilizing economical and non-toxic nanosized CuO: an efficient, robust and reusable catalyst for the C–O coupling reaction inO-arylation of phenol

“…It is also well known that hybrid phosphorus ligands are the most explored and the most commonly used building blocks for catalysts in industry as well as academia due to numerous reasons. 38–40 The π-acceptor character of phosphorus (soft donor) can stabilize a metal centre in a low oxidation state and the σ-donor ability of the hard donor ( e.g. nitrogen) makes the metal more susceptible to oxidative addition reactions.…”

Copper complexes of phosphorus dendrimers and their properties

“…Most of the properties of dendrimers depend on the type of terminal functions they bear. A number of dendrimers have been functionalized with metal complexes [5], in particular phosphorus-containing dendrimers [6,7]. These dendrimers are essentially of type phosphorhydrazone.…”

Phosphorus Dendrimers as Nanotools against Cancers

“…These dendrimers have generated hundreds of publications, first concerning the synthesis of very original dendritic structures [ 18 ], then for their use as catalysts [ 19 ], for elaborating nanomaterials [ 20 ], and in biology or nanomedicine [ 21 , 22 ]. Among the numerous properties of phosphorus dendrimers in the latter fields, one can cite their use against prion diseases [ 23 ]; against Alzheimer disease [ 24 ]; against HIV [ 25 , 26 ], against rheumatoid arthritis [ 27 ], uveitis [ 28 ], lung inflammation [ 29 ]; and against various types of cancers, which will be the main topic of this review.…”