Pseudo poly synthesis

Synthesis of "Pseudo" Poly(Amino Acid) 208 12.5.1 Synthesis of Carbonate-Based "Pseudo" ... 

FIGURE 12.2 Common amino acids used for synthesis of pseudo poly(amino acids). 

Synthesis of Ester-Based "Pseudo" Poly(Amino Acids)... 

Stimulated by extensive research activities on donor/acceptor substituted stilbenes, Mullen and Klarner have reported a donor/acceptor substituted poly(4,4 -biphenyl-diylvinylene) derivative (85) in which the NR2 donor and CN acceptor substituents are located on the vinylene unit [111]. The synthesis is based on a C-C-coupling reaction of in situ generated carbanion functions with a (pseudo)cation function, followed by a subsequent elimination of MeSH with formation of the olefinic double bond. 

Finally, it should be mentioned that there exist two other routes for the synthesis of copolymers. First the partial chemical conversion of homopolymers (see Sect. 5.1), for example, the partial hydrolysis of poly(vinyl acetate). Secondly, by homopolymerization of correspondingly built monomers. An example for these macromolecular compounds, sometimes called pseudo-copolymers, is the alternating copolymer of formaldehyde and ethylene oxide synthesized by ringopening polymerization of 1,3-dioxolane. 

Currently, the viability of this route to form poly(methacrylonitrile) has been illustrated. NMR spectroscopy is in progress to verify that the starting tacticity of the polymer chain has been maintained during this synthesis. As none of these reactions should involve a mechanism in which the pseudo-asymmetric centers along the polymer backbone are influenced, it is anticipated that this illustration will be possible. 

Polymerization of diallg l vinylphosphonate monomers was nevertheless efficiently carried out in the presence of lanthanide derivatives and especially cyclopentadienyl lanthanide complexes, used both as initiators and catalysts. Very recently, Shen et al performed the synthesis of poly (diethyl vinylphosphonate) using a lanthanide tris(borohydride) below 50 °C. The authors showed that the polymerization eould be controlled and proceeds under pseudo-first-order kinetics, giving rise to high molecular weight polymers, i.e. ranging from 20 to 40 kDa with molecular weight dispersity below 1.7. 

Conducting polymers constitute another category of promising pseudo-capacitive materials. The most common ones include polypyrrole (PPy), polyaniline (PANI), and poly-(3,4)-ethylenedioxythiophene (PEDOT). This group is of particular interest due to low cost and ease of synthesis. These compounds can be polymerized directly onto a collector material via EPD. Alternatively, the polymerization can be done within surfactant emulsions... 

Palladium-catalyzed cross-coupling is a powerful tool for the synthesis of various 7c-conjugated molecules and polymers through sp and sp carbon-carbon bond formation [17-20]. Scheme 3 shows the synthetic routes for poly (p-arylene-ethynylene)-type (PAE-type) jc-stacked polymers by Sonogashira-Hagihara cross-coupling [21, 22]. Polymer 13 was obtained from the monomers pseudo-para-dibromo[2.2]... 

Scheme 4 shows the synthesis of poly(/7-arylenevinylene)-type (PAV-type) jT-stacked polymer by Heck-Mizoroki cross-coupling [24, 25]. The treatment of pseudo-/7ara-divinyl[2.2]paracyclophane 14 with diiodofluorene 15 using a Pd(OAc)2/P(o-Tol)3/NBu3 catalytic system afforded the corresponding stacked polymer 16 in 96 % isolated yield with M =5,200 [26]. Poly(/7-arylene)-type (PA-type) jc-stacked polymers were prepared by Suzuki-Miyaura cross-coupling [27, 28], and a representative example is shown in Scheme 5. The Pd(PPh3)4-catalyzed polymerization of monomer 9 with bis(boronic acid ester) monomer 17 afforded the polymer 18 in 89 % isolated yield (Mn=2,600) [29].

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