And metal catalyzed coupling

The general approaches for the synthesis of poly(arylene ether)s include electrophilic aromatic substitution, nucleophilic aromatic substitution, and metal-catalyzed coupling reactions. Poly(arylene ether sulfone)s and poly(arylene ether ketone)s have quite similar structures and properties, and the synthesis approaches are quite similar in many respects. However, most of the poly(arylene ether sul-fone)s are amorphous while some of the poly(arylene ether)s are semicrystalline, which requires different reaction conditions and approaches to the synthesis of these two polymer families in many cases. In the following sections, the methods for the synthesis of these two families will be reviewed. 

Nicolau DV, Sawant PD (2005) Scanning Probe Microscopy Studies of Surface-Immobilised DNA/Oligonucleotide Molecules. 260 113-160 Niessen HG, Woelk K (2007) Investigations in Supercritical Fluids. 276 69-110 Nilsson P, Olofsson K, Larhed M (2006) Microwave-Assisted and Metal-Catalyzed Coupling Reactions. 266 103-144... 

Microwave-Assisted and Metal-Catalyzed Coupling Reactions... 

The synthesis of conjugated polymers is highly dependent on the effective carbon-carbon single bond generation between unsaturated carbons in aromatic molecules. Aromatic units in conjugated polymers can be benzene, aniline, pyrrole, thiophene, carbazole, naphthalenediimide, perylenediimide (PDI), or their derivatives, etc. Although monomers are various, their synthetic methods can be mainly classified into chemical and electrochemical polymerizations. Chemical polymerization includes chemical oxidative polymerization and metal-catalyzed coupling condensation. 

Nilsson, R, Olofsson, K., and Larhed, M. Microwave-assisted and metal-catalyzed coupling reactions. Top CurrChem 266,103-144 (2006). 

Nilsson P, Olofsson K, Larhed M (2006) Microwave-Assisted and Metal-Catalyzed Coupling Reactions. 266 103-144... 

Researchers fundamentally interested in C-C bond-forming methods for polyketide synthesis have at times viewed allylation methods as alternatives, and maybe even competitors, to aldol addition reactions. Both areas have dealt with similar stereochemical problems simple versus absolute stereocontrol, matched versus mismatched reactants. There are mechanistic similarities between both reaction classes open and closed transition states, and Lewis acid and base catalysis. Moreover, there is considerable overlap in the prominent players in each area boron, titanium, tin, silicon, to name but a few, and the evolution of advances in both areas have paralleled each other closely. However, this holds for an analysis that views the allylation products (C=C) merely as surrogates of or synthetic equivalents to aldol products (C=0). The recent advances in alkene chemistry, such as olefin metathesis and metal-catalyzed coupling reactions, underscore the synthetic utility and versatility of alkenes in their own right. In reality, allylation and aldol methods are complementary The examples included throughout the chapter highlight the versatility and rich opportunities that allylation chemistry has to offer in synthetic design. 

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