Single electron-transfer living radical

In addition, Percec and coworkers [253] reported that polymerizations in polar solvents in conjtmction with copper and appropriate ligands allow ultrafast syntheses of high-molecular-weight polymers at ambient temperature. The process is referred to as Single Electron Transfer-Living Radical Polymerization (SET-LRP). The mechanism proposed is based on disproportionation of cuprous ions to cupric ions and metallic copper. This is catalyzed by the polar solvents and the appropriate ligands. The proposed mechanism can be illustrated as follows ... 

Atom Transfer Radical Polymerization (ATRP) and Single-Electron Transfer-Living Radical Polymerization (SET-LRP)... 

Wright, P.M., Mantovani, G., Haddleton, D.M. 2008. Polymerization of Methyl Acrylate Mediated by Copper(O)/Me -TREN in Hydrophobic Media Enhanced by Phenols Single Electron Transfer-Living Radical Polymerization. I. Polvm. Sci. A Polvm. Chem. 46 7376-7385. 

Wang, W., Zhang, Z., Zhu, J., Zhou, N., Zhu, X. 2009. Single Electron Transfer-Living Radical Polymerization of Methyl Methacrylate in Fluoroalcohol Dual Control Over Molecular Weight and Tacticity. f. Polvm. Sci. A Polvm. Chem. 47 6316-6327. 

BCinetics of Cu(0)-Wire-Catalyzed Single-Electron Transfer Living Radical Polymerization of Methyl Acrylate in DMSO at 25°C. 42 2379-2386. 

Zoppe, J., Habibi, Y., Rojas, O.J., Venditti, R.A., Johansson, L.-S., Efimenko, K., Osterberg, M., Laine, J. 2010. Poly(N-lsopropylacrylamide) Brushes Grafted from Cellulose Nanocrystals via Surface-Initiated Single-Electron Transfer Living Radical Polymerization. Biomacromolecules 11 2683-2691. 

One major advantage of RAFT polymerization over many other RDRP techniques, such as ATRP, single electron transfer living radical polymerization (SET-LRP), and NMP, is its tolerance of functionality which is such that a wide range of groups can be introduced as substituents on R or Z groups. This functionality includes for use in click ... 

Coelho and co-workers have recently reported another use of water in living polymerisation in the synthesis of a block copolymer [poly(vinyl chloride)-b-poly(/z-butyl acrylate)-b-poly(vinyl chloride)].3 The new material was synthesised by single electron transfer/degenerative chain transfer-mediated living radical polymerisation (SET-DTLRP) in two steps. 

Single Electron Transfer - Degenerative Transfer Living Radical Polymerization with lodo-Compounds 165... 

Ruthenium catalysts found many applications in C-C bond formation reactions (selected reviews [157-161]). Ruthenium occurs mostly in oxidation states +2 and +3, but lower as well as higher oxidation states can easily be reached. Thus ruthenium compounds are frequently used in oxidative transformations proceeding by either single or two electron transfer pathways (selected reviews [162-164]). It has long been known that ruthenium complexes can be used for the photoactivation of organic molecules (selected reviews [165, 166]). Ruthenium complexes are applied as catalysts in controlled or living radical polymerizations [167-169]. 

Traylor (38) has also shown that biomimetic iron N-alkylporphyrins themselves are competent catalysts for epoxidation of alkenes with a rate constant of about 104 M-1 s-1. On the basis of these observations and rearrangement reactions of specific alkenes, Traylor has proposed the reaction sequence outlined in Scheme 3 as representative of the oxidation and N-alkylation reactions of the P-450 model systems. In this scheme, the epoxide and the N-alkylated heme are derived from a common, electron-transfer intermediate (caged ferrylporphyrin-alkene cation radical). Collman and co-workers (28, 29) prefer a concerted mechanism (or a short-lived, acyclic intermediate) for epoxidation and N-alkylation reactions. Both authors note that the reactions catalyzed by cytochrome P-450 (and biomimetic reactions) probably can not be ascribed to any single mechanism. 

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