Cross-coupling reactions polymer applications

Suzuki cross-coupling has found applications in the preparation of specialty polymers, too. Rigid rod polymers may have very useful properties (the well-known Kevlar, poly(p-phenyleneterephtalamide) belongs to this family, too) but they are typically difficult to synthetize, characterize and process. Such materials with good solubility in organic solvents [38] or in water [39] were obtained in the reactions of bifunctional starting compounds under conventional Suzuki conditions with [Pd(PPh3)4] and [Pd(TPPMS)3] catalysts, respectively (Scheme 6.15). 

In the decade since then, the major focus has been twofold improving the scope of such reactions and application of the cross-coupling reactions for the synthesis of thiophene dendrimers, thiophene polymers, and thiophenes as optoelectronic materials. 

The application of ESR spectrometry and in particular the determination of free radical concentrations in the interaction products between HAs and chlorophenoxyalkanoic compounds, has experimentally confirmed the occurrence of already suggested homolytic cross-coupling reactions, leading to the incorporation of xenobiotic chlorophenoxy units into the humic polymers through covalent bonds. 

Y. Zheng, P.D. Stevens, and Y. Gao Magnetic nanoparticles as an orthogonal support of polymer resins Applications to solid-phase Suzuki cross-coupling reactions. Journal of Organic Chemistry 71, 537-542 (2006)... 

Recently, several synthetic applications using such cross-coupling reactions have become powerful tools for the construction of new organic compounds. Among these reactions, aromatic-aromatic (or heteroaromatic) couplings are used most frequently, because of their importance in pharmaceutical processes and polymer sciences. 

New developments in the Suzuki cross-coupling reaction include the application of microwave, polymer-bound catalysts, nanoparticles, and ionic liquids as reaction medium. A discussion of these methods exceeds the scope of this chapter. 

Over the past two decades, Suzuki polycondensation has become one of the most efficient methods for the synthesis of conjugated polymers. As another important cross-coupling protocol, the Suzuki-Miyaura cross-coupling reaction was invented by Suzuki and co-workers in 1979 The scope of the Suzuki reaction for synthetic applications has been surveyed in several excellent reviews by Kotha, Lahiri, Kashinath, Miyaura and Fu. The Suzuki-Miyaura cross-coupling reaction provided deeper insights into how to connect two specific sp -hybridized C-atoms more efficiently and under milder conditions. The Suzuki-Miyaura cross-coupling reaction was first used by Schlueter et al. to prepare poly(para-phenylene)s. ... 

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