Kinetics of Acyclic Diene Metathesis (ADMET) Polymerization. Influence of the Negative Neighboring Group Effect

Wagener, Kenneth B.; Brzezinska, Krystyna R.; Anderson, J. D.; Younkin, Todd R.; Steppe, K.; Deboer, W.

doi:10.1021/ma970357w

Cited by 93 publications

(65 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…39 This effect generally occurs when fewer than two methylene spacers separate the coordinating group and the alkene, and it has been observed for a wide variety of functional groups, including ethers, 23 thioethers, 25 phosphates, 29 esters, 24 and carbonates. 26 With the aim of circumventing this potential problem, three different sulfonate ester-containing α,ω-diene monomers were synthesized, M1-M3, in which the sulfonate ester group was separated from the alkene with m = 2, 4, and 9 methylene groups, respectively.…”

Section: Monomer Synthesismentioning

confidence: 99%

Synthesis of poly(sulfonate ester)s by ADMET polymerization

et al. 2014

View full text Add to dashboard Cite

Many hydrocarbon polymers containing heteroatom defects in the main chain have been investigated as degradable polyethylene-like materials, including aliphatic polyesters. Here, acyclic diene metathesis (ADMET) polymerization was used for the synthesis of aliphatic poly(sulfonate ester)s. The requisite sulfonate ester containing α,ω-diene monomers with varying numbers of methylene groups were synthesized, and their polymerization in the presence of ruthenium-N-heterocyclic (Ru-NHC) alkylidene catalysts was studied. A clear negative neighboring group effect (NNGE) was observed for shorter dienes , either inhibiting polymerization or resulting in low-molecular-weight oligomers. The effect was absent when undec-10-en-1-yl undec-10-ene-1-sulfonate was employed as the monomer, and its ADMET polymerization afforded polymers with appreciable number-average molecular weights of up to 37,000 g/mol and a dispersity Đ of 1.8. These polymers were hydrogenated to afford the desired polyethylene-like systems. The thermal and morphological properties of both saturated and unsaturated polymers were investigated. The incorporation of sulfonate ester groups in the polymer backbone offers an interesting alternative to other heteroatoms and helps further the understanding of the effects of these defects on the overall polymer properties.

show abstract

Section: Monomer Synthesismentioning

confidence: 99%

Synthesis of poly(sulfonate ester)s by ADMET polymerization

et al. 2014

View full text Add to dashboard Cite

show abstract

“…This can be explained by the intramolecular coordination of the w-double bond of the alkylidene to the Ru atom in competition with the intermolecular coordination of tricyclohexylphosphine. [9,23,24] Moreover, the K + adduct ions 8 a-10 a showed a smooth intramolecular metathesis reaction in the gas phase and elimination of the respective cycloalkenes 11-13. Thus, we performed the first catalytic step of RCM in the liquid phase, transferred the intermediates 8 a·K + -10 a·K + in the gas phase and observed the second step of the RCM cycle.…”

mentioning

confidence: 96%

“…[2] It is known as well that ADMET polymerization of 1,5-hexadiene (22) is sluggish and preferentially cyclooctadiene is formed. [24] In order to check whether four-membered ring formation could occur in a gas phase through a RCM reaction, we studied the metathesis reaction of 1,5-hexadiene (22) with 1 in the presence of KCl (Scheme 7).…”

mentioning

confidence: 99%

ESIMS Studies and Calculations on Alkali‐Metal Adduct Ions of Ruthenium Olefin Metathesis Catalysts and Their Catalytic Activity in Metathesis Reactions

Wang

Yim

Klüner

et al. 2009

Chemistry A European J

View full text Add to dashboard Cite

Electrospray ionization mass spectrometry (ESIMS) and subsequent tandem mass spectrometry (MS/MS) analyses were used to study some important metathesis reactions with the first-generation ruthenium catalyst 1, focusing on the ruthenium complex intermediates in the catalytic cycle. In situ cationization with alkali cations (Li(+), Na(+), K(+), and Cs(+)) using a microreactor coupled directly to the ESI ion source allowed mass spectrometric detection and characterization of the ruthenium species present in solution and particularly the catalytically active monophosphine-ruthenium intermediates present in equilibrium with the respective bisphosphine-ruthenium species in solution. Moreover, the intrinsic catalytic activity of the cationized monophosphine-ruthenium complex 1 aK(+) was directly demonstrated by gas-phase reactions with 1-butene or ethene to give the propylidene Ru species 3 aK(+) and the methylidene Ru species 4 aK(+), respectively. Ring-closing metathesis (RCM) reactions of 1,6-heptadiene (5), 1,7-octadiene (6) and 1,8-nonadiene (7) were studied in the presence of KCl and the ruthenium alkylidene intermediates 8, 9, and 10, respectively, were detected as cationized monophosphine and bisphosphine ruthenium complexes. Acyclic diene metathesis (ADMET) polymerization of 1,9-decadiene (14) and ring-opening metathesis polymerization (ROMP) of cyclooctene (18) were studied analogously, and the expected ruthenium alkylidene intermediates were directly intercepted from reaction solution and characterized unambiguously by their isotopic patterns and ESIMS/MS. ADMET polymerization was not observed for 1,5-hexadiene (22), but the formation of the intramolecularly stabilized monophosphine ruthenium complex 23 a was seen. The ratio of the signal intensities of the respective with potassium cationized monophosphine and bisphosphine alkylidene Ru species varied from [I(4a)]/[I(4)]=0.02 to [I(23a)]/[I(23)]=10.2 and proved to be a sensitive and quantitative probe for intramolecular pi-complex formation of the monophosphine-ruthenium species and of double bonds in the alkylidene chain. MS/MS spectra revealed the intrinsic metathesis catalytic activity of the potassium adduct ions of the ruthenium alkylidene intermediates 8 a, 9 a, 10 a, 15 a, and 19 a, but not 23 a by elimination of the respective cycloalkene in the second step of RCM. Computations were performed to provide information about the structures of the alkali metal adduct ions of catalyst 1 and the influence of the alkali metal ions on the energy profile in the catalytic cycle of the metathesis reaction.

show abstract

“…1,2,4,6,14,15 To optimize the reaction conditions, several experiments were performed using different catalyst ratios to obtain high molecular weight polymer samples in the shortest possible electrolysis time and reaction time. The results shown in Table 1 summarize the optimum conditions for high conversion to polyoctenamer in comparison with those reported using other catalytic systems.…”

Section: Resultsmentioning

confidence: 99%

Electrochemically generated tungsten‐based active species as catalysts for metathesis‐related reactions: 1. Acyclic diene metathesis polymerization of 1,9‐decadiene

Dereli

Düz

Zümreoǧlu‐Karan

et al. 2002

Applied Organom Chemis

View full text Add to dashboard Cite

Electrochemically generated tungsten-based active Electrochemically generated tungsten-based active species as catalysts for metathesis-related reactions: 1. species as catalysts for metathesis-related reactions: 1. Acyclic diene metathesis polymerization of 1,9-decadiene Acyclic diene metathesis polymerization of 1,9-decadiene Okan Dereli, Bu È lent Du È z, Birgu È l Zu È mreog AE lu-Karan* and Yavuz I Ç mamog AE lu* Hacettepe University, Chemistry Department, 06532 Ankara, Turkey The application of the WCl 6 ±e À ±Al±CH 2 Cl 2 system to acyclic diene metathesis polymerization of 1,9-decadiene is reported. The polyoctenamer formed is of a weight-average molecular weight of 9000 with a polydispersity of 1.92. IR and NMR spectral analyses indicate the retention of the double bonds in the polymer structure with high trans content as expected from a step condensation reaction. This relatively stable catalytic system, however, also activates the competing vinyl addition reactions while being inactive in ring-closure metathesis reactions.

show abstract

Kinetics of Acyclic Diene Metathesis (ADMET) Polymerization. Influence of the Negative Neighboring Group Effect

Cited by 93 publications

References 21 publications

Synthesis of poly(sulfonate ester)s by ADMET polymerization

Synthesis of poly(sulfonate ester)s by ADMET polymerization

ESIMS Studies and Calculations on Alkali‐Metal Adduct Ions of Ruthenium Olefin Metathesis Catalysts and Their Catalytic Activity in Metathesis Reactions

Electrochemically generated tungsten‐based active species as catalysts for metathesis‐related reactions: 1. Acyclic diene metathesis polymerization of 1,9‐decadiene

Contact Info

Product

Resources

About