NMR studies on the mechanism of polymerization of cyclic olefins by a molybdenum catalyst

Johnston, Jay A.; Rinaldi, Peter L.; Farona, Michael F.

doi:10.1016/0304-5102(92)80159-e

Cited by 10 publications

(2 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…They exhibit four-way stereoisomerism, i.e., exo-exo , exo-endo , endo-exo , and endo-endo . Previously, the exo-exo - and endo-endo -NBDDs were polymerized using Re(CO) 5 Cl/EtAlCl 2 or Mo(CO) 5 py/EtAlCl 2 /Bu 4 NCl, in which the ROMP and addition polymerization occurred simultaneously. , Recently, the ROMPs of endo-exo - and exo-endo -NBDDs using W-based catalysts were reported in a patent . However, ROMPs of the other two stereoisomers have not been reported.…”

Section: Introductionmentioning

confidence: 99%

Four Stereoisomeric Norbornadiene Dimers Containing a Cyclopropane Ring: ROMP, Polymer Properties, and Post-Polymerization Modification

2022

View full text Add to dashboard Cite

The efficient and selective introduction of functional groups to hydrocarbon polymers enables facile access to new polymer materials with various physical properties. In the present study, we have focused on cyclopropane-containing norbornadiene dimers (NBDDs) as bifunctional monomers and post-polymerization modification (PPM) for the synthesis of functionalized cyclic olefin polymers (COPs). The ring-opening metathesis polymerization (ROMP) of the four NBDD stereoisomers (exo-exo, exo-endo, endo-exo, and endo-endo) and the subsequent hydrogenation proceeded selectively to give the corresponding COPs (H-poly(NBDD)s) with reactive cyclopropane moieties. There are distinct differences between the four isomers in terms of polymerization rate and the physical properties of the resultant polymers. The endo-exo- and endo-endo-NBDDs show lower ROMP reactivities than the exo-exo- and exo-endo-NBDDs due to steric hindrance. All of the polymers before and after hydrogenation are amorphous, regardless of annealing (with the exception for the unannealed H-poly(exo-endo-NBDD)). Compared with the polymers of the exo-norbornenyl isomers, their endo-counterparts show lower solubilities, higher glass transition temperatures, sharper X-ray diffraction peaks, and larger d-spacings. The highly soluble H-poly(exo-exo-NBDD) was employed for the PPM via protic acid-catalyzed cyclopropane ring-opening to produce six new COPs bearing acyloxy, alkoxy, or aryl groups. Although rearrangements occur during ring-opening presumably through nonclassical carbocations, the polymer structures were determined with reference to the reactions of their corresponding monomeric model compounds. The PPM with m-xylene, for example, proceeds regioselectively while maintaining a narrow molecular weight distribution to produce a xylyl-substituted COP with good solubility and high thermal stability.

show abstract

Section: Introductionmentioning

confidence: 99%

Four Stereoisomeric Norbornadiene Dimers Containing a Cyclopropane Ring: ROMP, Polymer Properties, and Post-Polymerization Modification

2022

View full text Add to dashboard Cite

show abstract

“…6 Reference 11.c Measured from spectrum c in Figure 1. 3 Isotope shift calculated from values in columns 3 and 4.e Reference 9, van der Yelden et al9 have proposed that the olefinic carbon resonances of polybutadienes be grouped into six…”

mentioning

confidence: 99%

Sequence distribution determination of deuterated polybutadiene by {deuterium}carbon-13 INEPT triple resonance NMR experiments

Li¹,

Hensley²,

Harwood³

et al. 1993

Macromolecules

Self Cite

View full text Add to dashboard Cite

Advances in the Metathesis of Olefins

Ivin

2009

Patai's Chemistry of Functional Groups

View full text Add to dashboard Cite

Introduction Catalysts, Intermediates, Initiator Efficiencies Acyclic Monoenes not Containing Functional Groups Acyclic Monoenes Containing Functional Groups The Carbonyl–Olefination Reaction Acyclic Diene Metathesis ( ADMET ) Ring‐Opening Metathesis Polymerization ( ROMP ) Of Cycloalkenes Copolymerization Polymerization of Acetylenes by Olefin Metathesis Catalysts Intramolecular Metathesis Reactions of Enynes and Dienynes Metathesis Reactions of Alkynes Involving Total Cleavage of the C  C Bond

show abstract

NMR studies on the mechanism of polymerization of cyclic olefins by a molybdenum catalyst

Cited by 10 publications

References 16 publications

Four Stereoisomeric Norbornadiene Dimers Containing a Cyclopropane Ring: ROMP, Polymer Properties, and Post-Polymerization Modification

Four Stereoisomeric Norbornadiene Dimers Containing a Cyclopropane Ring: ROMP, Polymer Properties, and Post-Polymerization Modification

Sequence distribution determination of deuterated polybutadiene by {deuterium}carbon-13 INEPT triple resonance NMR experiments

Advances in the Metathesis of Olefins

Contact Info

Product

Resources

About