Application of carbon arc‐generated Mo‐ and W‐based catalyst systems to the ROMP of norbornene

Düz, Bülent; Elbistan, Can Koray; Ece, Abdulilah; Sevin, Fatma

doi:10.1002/aoc.1518

Cited by 13 publications

(6 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For PNBE ( Figure S1 ) olefinic carbons appear at 134.3 ppm, and aliphatic carbons at 43.0, 39.6 and 33.4 ppm, with those at 43.0 and 39.6 ppm being characteristic of the trans and cis , respectively, configuration of the polymer chain. The assignment of those peaks to trans or cis structures is based on 13 C-NMR spectra of PNBE from the literature [ 35 ] and on the comparison of the 13 C CPMAS NMR spectra of PNBE obtained with the catalytic systems {W 2 } and RuCl 3 /H 2 O ( Figure 2 ). The catalytic system RuCl 3 /H 2 O is known to provide trans -PNBE [ 36 ].…”

Section: Resultsmentioning

confidence: 99%

Copolymerization of Norbornene and Norbornadiene Using a cis-Selective Bimetallic W-Based Catalytic System

et al. 2017

View full text Add to dashboard Cite

Abstract:The bimetallic cluster Na 3 Cl 4 (THF) 2 ]·(THF) 3 ({W 2 }, {W 3 W} 6+ , a 2 e 4 ), which features a triple metal-metal bond, is a highly efficient room-temperature initiator for ring opening metathesis polymerization (ROMP) of norbornene (NBE) and norbornadiene (NBD), providing high-cis polymers. In this work, {W 2 } was used for the copolymerization of the aforementioned monomers, yielding statistical poly(norbornene)/poly(norbornadiene) PNBE/PNBD copolymers of high molecular weight and high-cis content. The composition of the polymer chain was estimated by 13 C CPMAS NMR data and it was found that the ratio of PNBE/PNBD segments in the polymer chain was relative to the monomer molar ratio in the reaction mixture. The thermal properties of all copolymers were similar, resembled the properties of PNBD homopolymer and indicated a high degree of cross-linking. The morphology of all materials in this study was smooth and non-porous; copolymers with higher PNBE content featured a corrugated morphology. Glass transition temperatures were lower for the copolymers than for the homopolymers, providing a strong indication that those materials featured a branched-shaped structure. This conclusion was further supported by viscosity measurements of copolymers solutions in THF. The molecular structure of those materials can be controlled, potentially leading to well-defined star polymers via the "core-first" synthesis method. Therefore, {W 2 } is not only a cost-efficient, practical, highly active, and cis-stereoselective ROMP-initiator, but it can also be used for the synthesis of more complex macromolecular structures.

show abstract

Section: Resultsmentioning

confidence: 99%

Copolymerization of Norbornene and Norbornadiene Using a cis-Selective Bimetallic W-Based Catalytic System

et al. 2017

View full text Add to dashboard Cite

show abstract

“…All PNBE samples obtained were soluble in common organic solvents (CHCl 3 , CH 2 Cl 2 , THF). The configuration of the polymer was determined by 1 H- and 13 C-NMR spectra (Supplementary Material Figure S1) [18]. The relative proportions of double-bond pair sequences, represented as trans-cis ( tc ), trans-trans ( tt ), cis-cis ( cc ) and cis-trans ( ct ) units, were determined from the four methine carbon (C 1,4 ) signals of the 13 C-NMR spectrum of PNBE at δ C 43.67 ( tc ), 43.44 ( tt ), 38.88 ( cc ) and 38.67 ppm ( ct ).…”

Section: Resultsmentioning

confidence: 99%

“…The stereochemistry of the polymers obtained in this study was determined by 1 H- and 13 C-NMR [1,18,20,26,32,36].…”

Section: Methodsmentioning

confidence: 99%

Exploring the Reactivity of Na[W2(μ-Cl)3Cl4(THF)2]∙(THF)3 towards the Polymerization of Selected Cycloolefins

et al. 2015

View full text Add to dashboard Cite

Abstract:The bimetallic compound Na 3 Cl 4 (THF) 2 ]¨(THF) 3 (1, {W 3 W} 6+ , a 12 e 14 ) is a highly efficient room-temperature initiator for ring opening metathesis polymerization (ROMP) of norbornene (NBE) and some of its derivatives. In most cases, addition of phenylacetylene (PA) as co-initiator improves the catalytic activity and retains the high cis-stereoselectivity. On the other hand, 1 can polymerize cyclopentadiene (CPD), not via a metathetic, but rather, via a cationic mechanism. Here, we present a comparison of the reactivity of the two catalytic systems (1 and 1/PA) between themselves and with other systems reported in the literature, the characterization of the polymers formed and mechanistic aspects of the corresponding reactions.

show abstract

“…The stereochemistry of the polymers obtained (PNBE, PNBE-COOME, PVNBE and the soluble part of PNBD) was determined by 1 H and 13 C NMR [28][29][30][31][32]. tt).…”

Section: Polymer Microstructurementioning

confidence: 99%

Ring Opening Metathesis Polymerization of Norbornene and Derivatives by the Triply Bonded Ditungsten Complex Na[W2(µ-Cl)3Cl4(THF)2]·(THF)3

et al. 2012

View full text Add to dashboard Cite

Abstract:In this study, the reactions of the bimetallic compound Na 3 ) with norbornene (NBE) and some of its derivatives (5-X-2-NBE; X = COOH (NBE-COOH), OH (NBE-OH), CN (NBE-CN), COOMe (NBE-COOMe), CH=CH 2 (VNBE); norbornadiene (NBD)) are described. Complex 1 contains a tungsten-tungsten triple bond, bearing three halide bridges and two labile THF ligands, in a cisoidal relationship along the metal-metal axis. The complex was found to be a highly efficient room temperature homogeneous and heterogeneous unicomponent initiator for the catalytic ring opening metathesis polymerization (ROMP) of most substrates. NBE provides polynorbornene (PNBE) of high molecular weight (M w ) in high yields, soluble in organic solvents. The reaction proceeds with high cis-stereoselectivity (80%-86% cis), independently of the reaction conditions. Strongly coordinating pendant groups (-COOH, -OH, -CN) deactivate 1, whereas substrates bearing softer ones (-COOMe, -CH=CH 2 ) are quantitatively polymerized. NBD gives

show abstract

Application of carbon arc‐generated Mo‐ and W‐based catalyst systems to the ROMP of norbornene

Cited by 13 publications

References 22 publications

Copolymerization of Norbornene and Norbornadiene Using a cis-Selective Bimetallic W-Based Catalytic System

Copolymerization of Norbornene and Norbornadiene Using a cis-Selective Bimetallic W-Based Catalytic System

Exploring the Reactivity of Na[W2(μ-Cl)3Cl4(THF)2]∙(THF)3 towards the Polymerization of Selected Cycloolefins

Ring Opening Metathesis Polymerization of Norbornene and Derivatives by the Triply Bonded Ditungsten Complex Na[W2(µ-Cl)3Cl4(THF)2]·(THF)3

Contact Info

Product

Resources

About