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Poly , Suzuki

The dibromo- (and diiodo-) stilbenes ate potentially useful monomers tor the synthesis of poly(p-phenylenevinylenes) via poly-Heck or poly-Suzuki coupling reactions. ... [Pg.29]

Later, the same methodology was applied by Wallow and Novak for the synthesis of water-soluble poly(p-phenylene) derivatives via the poly-Suzuki reaction of 4,4 -biphenylylene bis(boronic acid) with 4,4 -dibromodiphenic acid in aqueous di-methylformamide [26]. These aromatic, rigid-chain polymers exhibit outstanding thermal stability (decomposition above 500 °C) and play an important role in high-performance engineering materials [27] conducting polymers [28] and nonlinear optical materials [29]. [Pg.518]

Interfacial adhesion and, thereby, compatibility can be enhanced by the selective crosslinking reaction in polymer blends. Inoue and Suzuki [26] reported the properties of blends dynamically crosslinked PP-EPDM blends. The crosslinking agent was yV,N -/w-phenylene-bismaleimide - poly(2,2,4 - trimethyl - 1,2-dihydroquino -line) system. Increase in interfacial adhesion leads to... [Pg.640]

The Suzuki reaction was also used to prepare the polyketone since this particular reaction tolerates the subsequent step (Scheme 6.19).135 Palladium-catalyzed cross-coupling of aromatic diacid chlorides and bis(trimethylstannane) monomers was utilized to prepare poly(arylene ether ketone)s.136... [Pg.347]

At about die same time, die application of the Suzuki coupling, the crosscoupling of boronic acids widi aryl-alkenyl halides in die presence of a base and a catalytic amount of palladium catalyst (Scheme 9.12),16 for step-growth polymerization also appeared. Schliiter et al. reported die synthesis of soluble poly(para-phenylene)s by using the Suzuki coupling condition in 1989 (Scheme 9.13).17 Because aryl-alkenyl boronic acids are readily available and moisture stable, the Suzuki coupling became one of die most commonly used mediods for die synthesis of a variety of polymers.18... [Pg.470]

Synthesis of Poly(p-phenylene) 24 by Using Suzuki Coupling11... [Pg.491]

In 1996, Wegner et al. published the synthesis of poly(oligophenylenevinyle-ne)s (96), consisting of biphenylene-, terphenylene- and quinquephenylene moieties as aromatic building blocks, via Suzuki-type aryl-aryl cross coupling of AA/BB-type monomers [121]. By judicious choice of the arylene moieties, the optical properties of the resulting polymers can be tailored within a wide range. [Pg.208]

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]

Morimoto, K. and Suzuki, S., "Ultraviolet Irradiation of Poly(alkyl Acrylates) and Poly(alkyl Methacrylates)", J. Appl. Polym. Sci., 1972, 16, 2947-2961. [Pg.196]

Similar Suzuki couplings have been performed by Hu and coworkers utilizing a poly(dicyclohexylcarbodiimide)/palladium nanoparticle composite [152]. This PDHC-Pd catalyst showed remarkable activity and stability under microwave irradiation. Near quantitative conversion (95% isolated yield) was obtained after 40 min of microwave heating of a mixture of iodobenzene with phenylboronic acid in dioxane. Re-using the immobilized catalyzed showed no significant loss of efficiency, as the fifth cycle still furnished a 90% isolated yield of the desired biphenyl. [Pg.383]

J. Terao, A. Tang, J.J. Michels, A. Krivokapic, and H.L. Anderson, Synthesis of poly(p-phenylene vinylene) rotaxanes by aqueous Suzuki coupling, Chem. Commun. 56-57, 2004. [Pg.268]

Y. Wu, J. Li, Y. Fu, and Z. Bo, Synthesis and extremely stable blue light emitting poly(spirobi-fluorene)s with Suzuki polycondensation, Org. Lett., 6 3485-3487, 2004. [Pg.274]

S. Guillerez and G. Bidan, New convenient synthesis of highly regioregular poly(3-octylthiophene) based on the Suzuki coupling reaction, Synth. Met., 93 123-126, 1998. [Pg.282]

Greater durability of the colloidal Pd/C catalysts was also observed in this case. The catalytic activity was found to have declined much less than a conventionally manufactured Pd/C catalyst after recycling both catalysts 25 times under similar conditions. Obviously, the lipophilic (Oct)4NCl surfactant layer prevents the colloid particles from coagulating and being poisoned in the alkaline aqueous reaction medium. Shape-selective hydrocarbon oxidation catalysts have been described, where active Pt colloid particles are present exclusively in the pores of ultramicroscopic tungsten heteropoly compounds [162], Phosphine-free Suzuki and Heck reactions involving iodo-, bromo-or activated chloroatoms were performed catalytically with ammonium salt- or poly(vinylpyrroli-done)-stabilized palladium or palladium nickel colloids (Equation 3.9) [162, 163],... [Pg.81]

Over the past decade, literally dozens of new AB2-type monomers have been reported leading to an enormously diverse array of hyperbranched structures. Some general types include poly(phenylenes) obtained by Suzuki-coupling [54, 55], poly(phenylacetylenes prepared by Heck-reaction [58], polycarbosilanes, polycarbosiloxanes [59], and polysiloxysilanes by hydrosilylation [60], poly(ether ketones) by nucleophilic aromatic substitution [61] and polyesters [62] or polyethers by polycondensations [63] or by ring opening [64]. [Pg.17]

Chung, J. E., Yokoyama, M., Suzuki, K., Aoyagi, T., Sakurai, Y, and Okano, T. Reversibly thermo-responsive alkyl-terminated poly(A-isopropylacrylamide) coreshell micellar structures. Colloids Surfaces (B Biointerfaces), 1997, 9, 37-48. [Pg.48]

Bergbreiter reported that poly(N-isopropylacrylamide)-bound phosphine ligands (PNIPAM-resins) coordinated with the Pd(0) moieties afford efficient catalysts (46) for the Heck, Suzuki and sp-sp cross-coupling reactions (Scheme 4.30) [122]. [Pg.227]

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). [Pg.173]

The ease of degradation of the polyketone intermediate of Suzuki, obtained by oxidation of poly(vinyl alcohol), has been demonstrated by Wang and Huang(37) at the University of Connecticut. [Pg.6]

Ichikawa Y, Suzuki J, Washiyama J, Moteki Y, Noguchi K, Okuyama K (1994) Strain-induced crystal modification in poly(tetramethylene succinate). Polymer 35 3338... [Pg.312]


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See also in sourсe #XX -- [ Pg.141 , Pg.143 ]




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