Synthesis of Stereoregular Poly(phenylacetylene)s by Organorhodium Complexes in Aqueous Media

Tang, Ben Zhong; Poon, Wan Hong; Leung, Siu Fung; Leung, Wa Hung; Peng, Han

doi:10.1021/ma961573s

Cited by 165 publications

(177 citation statements)

References 34 publications

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“…However, there is not an obvious correlation between the length of the flexible chain (n) or the donor group (Z), and the catalytic activity or the molecular weight of the obtained polymers ( The solvent plays a decisive role in the polymerization reactions. 40,41 The catalytic activity of 5 is superior in toluene or in toluene/polar solvent mixtures but the polymers show bimodal molecular weight distributions. In contrast, the catalytic activity decreases when increasing the dielectric constant of the solvent but, interestingly, the polymers display unimodal GPC traces.…”

Section: Discussionmentioning

confidence: 99%

“…In general, rhodium complexes with nbd as diene ligand were found to be more active than those of cod, 42 although there are remarkable exceptions. 40,43 27 This fact has been explained in terms of the different π-acidity of the diene ligands. Thus, the high π-acidity of tfb results in the reduction of the electronic density at the rhodium center enhancing its electrophilic character that, in turn, facilitates the coordination of the monomer.…”

Section: Discussionmentioning

confidence: 99%

“…It is noticeable that catalytic systems based on rhodium complexes are, in general, tolerant with water. [40][41][42] We have found that the addition of water has a positive effect on the catalytic activity ( Figure 6) which can be rationalized in terms of a more facile proton transfer process but, at the same time, the termination step is also favored multiplying the number of different polymeric species giving broader GPC profiles.…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Cationic Rhodium Complexes with Hemilabile Phosphine Ligands as Polymerization Catalyst for High Molecular Weight Stereoregular Poly(phenylacetylene)

Jiménez¹,

Pérez‐Torrente²,

Bartolomé³

et al. 2009

Macromolecules

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A series of cationic complexes [Rh(diene){Ph 2 P(CH 2 ) n Z}] [BF 4 ] (diene = 1,5-cyclooctadiene (cod), tetrafluorobenzobarralene (tfb) or 2,5-norbonadiene (nbd)) containing functionalized phosphine ligands of the type Ph 2 P(CH 2 ) n Z (n = 2, or 3; Z = OMe, NMe 2 , SMe) have been prepared and characterized. These complexes have shown a great catalytic activity for phenylacetylene (PA) polymerization. Catalyst screening and optimization have determined the superior performance of complexes containing a P,N-functionalyzed phosphine ligand, [Rh(diene){Ph 2 P(CH 2 ) 3 NMe 2 }][BF 4 ] (diene = cod 5, tfb 6, nbd 7), and tetrahydrofuran as solvent. The influence of the diene ligand and the effect of temperature, PA to rhodium molar ratio, addition of water or a co-catalyst, DMAP (4-(dimethylamino)pyridine), have been studied. Diene ligands strongly influence the catalytic activity and complexes 6 and 7 are far more active than 5. Both complexes gave polyphenylacetylene (PPA) with very high number-average molecular weights (M n ) of 970 000 (6) and 1 420 000 (7). The addition of DMAP resulted in a dramatic drop in the PPA molecular weight, 106 000 (6) and 233 000 (7,). The PPA obtained with the system 6/DMAP showed a narrow molecular weight distribution (M w /M n = 1.20) and incremental monomer addition experiments have demonstrated the quasi-living nature of the polymerization reaction under these conditions. The PPA obtained with these catalytic systems has been characterized by 1 H and 13 C{ 1 H} NMR spectroscopy and shows a cis-transoidal configuration with a high level of steroregularity (cis content superior to 99%). TGA, DSC, and IR analysis have revealed a thermal cis↔trans

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Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Cationic Rhodium Complexes with Hemilabile Phosphine Ligands as Polymerization Catalyst for High Molecular Weight Stereoregular Poly(phenylacetylene)

Jiménez¹,

Pérez‐Torrente²,

Bartolomé³

et al. 2009

Macromolecules

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“…It is interesting to note that Rh-catalyzed polymerization proceeds even in water. 60 Though we started the research of Rh catalysts rather late, we could develop highly active catalysts and living polymerization catalysts.…”

Section: Rh Catalystsmentioning

confidence: 99%

Substituted polyacetylenes

Masuda

2006

J. Polym. Sci. A Polym. Chem.

389

222

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This article reviews the chemistry of substituted polyacetylenes developed by our research group, more specifically, development of polymerization catalyst, synthesis of new polymers, elucidation of their structure, investigation of their properties, and development of their functions. The main features are as follows: a number of catalysts based on group 5, 6, and 9 transition metals (Nb, Ta, Mo, W, and Rh) have been developed, which include living polymerization catalysts. By using these catalysts, many new substituted polyacetylenes have been synthesized, whose molecular weights are very high (Mw = 104−106). Most of the polymers are soluble in many common solvents and stable enough in the air unlike polyacetylene. Some of these polymers exhibit interesting functions including high gas permeability and photoelectronic properties. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 165–180, 2007

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“…These matters depend mainly on the low polymerizability of the rotaxane-containing monomer due to the wheel component working as a sterically hindered group toward the growing end; competitive occurrence of the dethreading of the wheel component during polymerization when a pseudorotaxane monomer is used; and a nonstereoregular main chain polymer being formed by the polymerization of vinylic monomer. 9 Polymerization of a vinylic rotaxane monomer but not pseudorotaxane monomer has been reported only by Osakada et al 11 To overcome such issues, we have noticed and studied the synthesis of ethynyl-functionalized rotaxane monomer for high polymerization and its derivation to polyacetylene, because the high polymerization of bulky acetylenes is readily achieved with appropriate catalysts, [22][23][24][25][26][27][28][29] and polyacetylenes usually have a stable main chain conformation. In this paper, we wish to disclose the synthesis of phenylacetylene monomers tethering rotaxane moieties and their polymerization to novel side chain-type polyrotaxanes.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of acetylene-functionalized [2]rotaxane monomers directed toward side chain-type polyrotaxanes

Nakazono

Fukasawa

Sato

et al. 2010

Polym J

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A crown ether-ammonium salt-type rotaxane monomer was synthesized in a high yield using dibenzo-24-crown-8-ether and sec-ammonium salt having a hydroxy terminal by means of an end-capping reaction with an ethynyl benzoic acid. Its N-acetylated derivative was also synthesized in a quantitative yield using excess acetic anhydride and triethylamine. Novel side chain-type polyrotaxanes, that is, ammonium-type and neutral polyphenylacetylenes tethering rotaxane moieties in side chains with high molecular weights, were obtained in high yields by polymerizations with an Rh catalyst. The structures of the polymers were characterized by infrared, ultraviolet-visible (UV-vis) spectra and size exclusion chromatography. N-acetylation of the rotaxane moieties of the ammonium salt-type polymer resulted in the formation of a reddish-colored neutral polymer showing red-shifted UV-vis absorptions around 500 nm based on the conjugated main chain, according to the structural change of rotaxane side chains, that is, the change of the distance of the wheel component to the polyacetylene main chain. The solubility of the polymers was evaluated.

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Synthesis of Stereoregular Poly(phenylacetylene)s by Organorhodium Complexes in Aqueous Media

Cited by 165 publications

References 34 publications

Cationic Rhodium Complexes with Hemilabile Phosphine Ligands as Polymerization Catalyst for High Molecular Weight Stereoregular Poly(phenylacetylene)

Cationic Rhodium Complexes with Hemilabile Phosphine Ligands as Polymerization Catalyst for High Molecular Weight Stereoregular Poly(phenylacetylene)

Substituted polyacetylenes

Synthesis of acetylene-functionalized [2]rotaxane monomers directed toward side chain-type polyrotaxanes

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