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Suzuki reactions polymerization

Suzuki Reaction Polymerizations. The Pd-catalyzed cross-coupling reaction of an organic electrophile and an organoboron compound in the presence of base has been extensively applied to the synthesis of polyphenylenes and related polymers. Well defined structures are obtained as a result of the regiospecificity of the Suzuki reaction (84) (230). The solubility of the polymers is commonly enhanced by the presence of alkyl or other types of substituents [for example see equations 85-87 (231,232,233 respectively and 254)]. [Pg.39]

As an example, consider the use of PVPy as a solid poison in the study of poly(noibomene)-supported Pd-NHC complexes in Suzuki reactions of aryl chlorides and phenylboroiuc acid in DMF (23). This polymeric piecatalyst is soluble under some of the reaction conditions employed and thus it presents a different situation from the work using porous, insoluble oxide catalysts (12-13). Like past studies, addition of PVPy resulted in a reduction in reaction yield. However, the reaction solution was observed to become noticeably more viscous, and the cause of the reduced yield - catalyst poisoning vs. transport limitations on reaction kinetics - was not immediately obvious. The authors thus added a non-functionalized poly(styrene), which should only affect the reaction via non-specific physical means (e.g., increase in solution viscosity, etc.), and also observed a decrease in reaction yield. They thus demonstrated a drawback in the use of the potentially swellable PVPy with soluble (23) or swellable (20) catalysts in certain solvents. [Pg.196]

The palladium-catalyzed coupling of boronic acids with aryl and alkenyl halides, the Suzuki reaction, is one of the most efficient C-C cross-coupling processes used in reactions on polymeric supports. These coupling reactions requires only gentle heating to 60-80 °C and the boronic acids used are nontoxic and stable towards air and water. The mild reaction conditions have made this reaction a powerful and widely used tool in the organic synthesis. When the Suzuki reaction is transferred to a solid support, the boronic add can be immobilized or used as a liquid reactant Carboni and Carreaux recently reported the preparation of the macroporous support that can be employed to efficiently immobilize and transform functionalized arylboronic adds (Scheme 3.12) [107, 246, 247]. [Pg.166]

Interestingly, the Suzuki reaction was shown to proceed smoothly also on polymeric support as early as ten years ago, and high yields of a variety of products were reported under these reaction conditions (Scheme 52) [130]. [Pg.129]

Interestingly, the Suzuki reaction was shown to proceed smoothly on polymeric supports as long as ten years ago and high yields of a variety of products were reported under these reaction conditions (Scheme 15.11) [38]. 4-Bromo and 4-iodobenzoic acids linked to Rink-amide TentaGel resulted in a conversion of more than 99% within 4 min. The yields suggested high potential for use of microwave-assisted reactions on polymeric resins [39]. [Pg.690]

Thiophene Copolymers. A copolymer from N-vinylcarbazole and thiophene, poly(2,7-bi-2-thienyl-9-vinyl-9-//-carbazole) was synthesized via a radical polymerization and a Suzuki reaction [58]. [Pg.9]

Zhang XJ, Bian N, Mao LJ et al (2012) Porous polybenzimidazoles via template-free suzuki coupling polymerization preparation, porosity, and heterogeneous catalytic activity in kno-evenagel condensation reactions. MacromolChem Phys 213 1575-1581... [Pg.180]

Recently, Seyler et al. reported a continuous-flow methodology for Suzuki coupling polymerization. poly(9,9-dioctylfluorene) (PFO) using this method shows a quite high molecular weight of 62 000 within only 30 min. This reaction time is comparable to that of microwave-assisted polymerization. [Pg.121]

Though both Suzuki and Stille reactions have been widely used to prepare conjugated polymers (including D-A copolymers), there are some subtle issues to consider when it comes to choose which reaction to use. For example, it is worth noting that the electron richness of stannyl aromatics decides whether these monomers are suitable for Stille-based polymerization or not. Mechanistically, relatively electron-rich thiophenes undergo the transmetalation step more readily than stannylbenzenes. Thus, stannylbenzenes experience low reactivity under Stille reaction conditions. Correspondingly, most thiophene-based aromatics are polymerized via Stille reactions, whereas a Suzuki reaction is a better option for benzene-based compounds. For example, fluorene and carbazole based polymers are usually prepared by Suzuki reaction, whereas polymers with cyclo-penta[2,l- ) 3,4-6 ]dithiophene, silolo[3,2- 4,5- ) ]dithiophene or benzo[l,2- 4,5-i Jdithiophene are often polymerized via Stille reaction. Due to its broader utilization over the Suzuki reaction in preparing D-A copolymers, Stille reaction-based polymerization will be the focus of this chapter, with a brief discussion on the Suzuki-based polymerization also included (Section 15.2.3). [Pg.345]

The Suzuki reaction shares many common similarities and features with aforementioned Stille reaction, such as similar catalytic cycles and Pd-based catalysts, and wide tolerance of functionalities. Highlighted below are a few notable factors one needs to consider when choosing Suzuki polymerization to prepare D A polymers. Interested readers are referred to a more general review for details on Suzuki polycondensation." ... [Pg.346]

Bushby reported several aminium-based polymers (22). Polyamine 5a (Mw > 10, GPC) was prepared by Suzuki reaction based polymerization, and then p-doped with antimony pentachloride. The resultant polyaminiiun polymer 5b had radical concentration of 0.5 radical/imit and an average value of S 4 (22). The ferromagnetic coupling was rather weak, as expected for extended exchange pathway of m-phenylene with two jo-phenylene spacers (Fig. 3). [Pg.4362]

Dendritic catalysis have been used in various chemical reactions, including the Suzuki-Miyaura reaction, Mizoroki-Heck reaction, hydrogenation reaction, carbonylation and hydroformylation reactions, oxidation reaction, polymerization and oligomerization reactions, arylation reaction, alkylation reaction, and asymmetric synthesis [6]. Recently, dendritic catalysts have been reviewed by Astmc et al. [6], In another review article. Reek et al. reviewed the applications of dendrimers as support for recoverable catalysts and reagents [58]. The authors believed that catalytic performance in these systems depends on used dendritic architecture. [Pg.187]

Several new polymeric structures (Scheme 6.24) were obtained by means of the Suzuki reaction [77]. They combine terphenyl subunits with other organic functional groups, thus illustrating the versatility of this reaction. [Pg.222]

Suzuki coupling polymerization Bromo-alkane functionalized polymers Glucothiose Thioetherification reaction — None (linear polymer) [103]... [Pg.82]

Stille Reaction Polymerizations. Although the Stille reaction has not been as widely applied to polymer synthesis as the Suzuki reaction, a number of different monomer pairs can participate in the reaction to give a variety of polymer types (equation 105) (250). [Pg.46]

Notable features of this synthesis are the Suzuki-reaction between sp -sp -carbons and the use of a cuprate reagent on solid phase. Janda et al. have published a prostaglandin synthesis using a soluble polymeric support [98]. [Pg.225]


See other pages where Suzuki reactions polymerization is mentioned: [Pg.218]    [Pg.197]    [Pg.391]    [Pg.189]    [Pg.199]    [Pg.36]    [Pg.3]    [Pg.741]    [Pg.8]    [Pg.19]    [Pg.633]    [Pg.48]    [Pg.1135]    [Pg.769]    [Pg.217]    [Pg.121]    [Pg.344]    [Pg.346]    [Pg.264]    [Pg.228]    [Pg.10]    [Pg.171]    [Pg.235]    [Pg.120]    [Pg.315]    [Pg.489]   


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