Metal halides, organometallic polymers

Allylzinc halides, with polymer-supported imines, 2, 398 [(7t-Allyl)zirconoxyl]carbenes, preparation, 4, 921 a-Activation, metal fluoroalkyls and fluoroaryls, 1, 735 Altemaric acid, via Alder-ene reactions, 10, 595 Alternative solvents, for green organometallic chemistry fluorous media, 12, 844 ionic liquids, 12, 846... 

Lithiation Reactions. One of the earliest reactions of this type made use of metal-halogen exchange reactions carried out on poly[bis(p-bromophenoxy)phosphazene]. Polyphosphazenes that bear p-bromophenoxy side oups are normally unreactive. However, they can be lithiated, as shown in Scheme III, and the lithio derivatives react with a wide variety of electrophiles that range from chlorophosphines (19) to organometallic halides (42-45), This provides an access route to polymer-bound transition metal catalysts and other metallated or silylated polymers. 

Provided the rate of capture of the propagating radicals by metal halide is faster than the rate of radical recombination (or disproportionation), quasi-living conditions are achieved, and a controlled synthesis of polymers or (block) co-polymers is possible. It is now reasonably well understood what factors are important in governing both the rate and equilibrium involved in reversible halogen abstraction, and while organometallic complexes, particularly of and Ni, have been employed in ATRP, the complexes have generally featured (7r-bound... 

Historically, complex mixtures, usually based on a metal halide or oxo-halide, a tin alkyl, an alcohol, and an additive, have been used to generate the metal alkylidene in situ. However, with these initiators, usually no control is achieved and thus the polymers produced by such ill-defined systems display broad dispersities. With organometallic coordination catalyst systems containing molybdenum or tungsten, it is possible to bring about ROP of cycloolefins to linear unsaturated polymers, for example, of cyclopentene to poly (1 -pentenylene). 

Acetyl ligands, in niobium complexes, C-H BDEs, 1, 298 Achiral phosphines, on polymer-supported peptides, 12, 698 Acid halides, indium compound reactions, 9, 683 Acidity, one-electron oxidized metal hydrides, 1, 294 Acid leaching, in organometallic stability studies, 12, 612 Acid-platinum rf-monoalkynes, interactions, 8, 641 Acrylate, polymerization with aluminum catalysts, 3, 280 Acrylic monomers, lanthanide-catalyzed polymerization,... 

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