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Controlled Ring-Opening Metathesis Polymerization with Polyisobutylene-Bound Pyridine-Ligated Ru(II) Catalysts.

ABSTRACT: This study describes the use of polyisobutylene (PIB) to phase-anchor pyridine ligands that form a phase-separable Grubbs third-generation catalyst. We further show that this complex is useful in ring-opening metathesis polymerization (ROMP) reactions. These PIB-bound pyridine-ligated Grubbs catalysts provide the same benefits of control over polymer chain growth and polydispersity of the product as their low-molecular-weight analogs and reduce Ru leaching in ROMP products from approximately 16% (820 ppm residues) as seen with a similar pyridine-ligated catalyst to a value of approximately 3% (160 ppm residues). These labile ligands are shown to be as effective at generating separable metal complexes as less labile PIB-functionalized N-heterocyclic carbene catalyst ligands that are typically used for immobilization but that require a multistep synthesis.

SUBMITTER: Suriboot J

PROVIDER: S-EPMC6640752 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Controlled Ring-Opening Metathesis Polymerization with Polyisobutylene-Bound Pyridine-Ligated Ru(II) Catalysts.

Suriboot Jakkrit J Hu Yue Y Malinski Thomas J TJ Bazzi Hassan S HS Bergbreiter David E DE

ACS omega 20161027 4

This study describes the use of polyisobutylene (PIB) to phase-anchor pyridine ligands that form a phase-separable Grubbs third-generation catalyst. We further show that this complex is useful in ring-opening metathesis polymerization (ROMP) reactions. These PIB-bound pyridine-ligated Grubbs catalysts provide the same benefits of control over polymer chain growth and polydispersity of the product as their low-molecular-weight analogs and reduce Ru leaching in ROMP products from approximately 16% ...[more]

PMID: 31457158

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