Mechanistic Insights into Ni(II)-Catalyzed Nonalternating Ethylene-Carbon Monoxide Copolymerization

Polyethylene materials with in-chain-incorporated keto groups were recently enabled by nonalternating copolymerization of ethylene with carbon monoxide in the presence of Ni(II) phosphinephenolate catalysts. We elucidate the mechanism of this long-sought-for reaction by a combined theoretical DFT study of catalytically active species and the experimental study of polymer microstructures formed in pressure-reactor copolymerizations with different catalysts. The pathway leading to the desired nonalternating incorporation proceeds via the cis/trans isomerization of an alkyl-olefin intermediate as the rate-determining step. The formation of alternating motifs is determined by the barrier for the opening of the six-membered C,O-chelate by ethylene binding as the decisive step. An η2-coordination of a P-bound aromatic moiety axially oriented to the metal center is a crucial feature of these Ni(II) catalysts, which also modulates the competition between the two pathways. The conformational constraints imposed in a 2',6'-dimethoxybiphenyl moiety overall result in a desirable combination of disfavoring ethylene coordination along the alternating incorporation pathway, which is primarily governed by electronics, while not overly penalizing the nonalternating chain growth, which is primarily governed by sterics.

Fachgebiet (DDC)

540 Chemie

Zitieren

ISO 690

VOCCIA, Maria, Lukas ODENWALD, Maximilian BAUR, Fei LIN, Laura FALIVENE, Stefan MECKING, Lucia CAPORASO, 2022. Mechanistic Insights into Ni(II)-Catalyzed Nonalternating Ethylene-Carbon Monoxide Copolymerization. In: Journal of the American Chemical Society. American Chemical Society (ACS). 144(33), pp. 15111-15117. ISSN 0002-7863. eISSN 1520-5126. Available under: doi: 10.1021/jacs.2c04563

BibTex

@article{Voccia2022-08-24Mecha-58260,
  year={2022},
  doi={10.1021/jacs.2c04563},
  title={Mechanistic Insights into Ni(II)-Catalyzed Nonalternating Ethylene-Carbon Monoxide Copolymerization},
  number={33},
  volume={144},
  issn={0002-7863},
  journal={Journal of the American Chemical Society},
  pages={15111--15117},
  author={Voccia, Maria and Odenwald, Lukas and Baur, Maximilian and Lin, Fei and Falivene, Laura and Mecking, Stefan and Caporaso, Lucia}
}

RDF

<rdf:RDF
    xmlns:dcterms="http://purl.org/dc/terms/"
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:bibo="http://purl.org/ontology/bibo/"
    xmlns:dspace="http://digital-repositories.org/ontologies/dspace/0.1.0#"
    xmlns:foaf="http://xmlns.com/foaf/0.1/"
    xmlns:void="http://rdfs.org/ns/void#"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema#" > 
  <rdf:Description rdf:about="https://kops.uni-konstanz.de/server/rdf/resource/123456789/58260">
    <dc:contributor>Odenwald, Lukas</dc:contributor>
    <dc:creator>Odenwald, Lukas</dc:creator>
    <dc:contributor>Falivene, Laura</dc:contributor>
    <dspace:hasBitstream rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/58260/1/Voccia_2-vh0fd0j3xnf71.pdf"/>
    <dc:language>eng</dc:language>
    <dspace:isPartOfCollection rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/29"/>
    <dc:date rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2022-08-10T08:22:46Z</dc:date>
    <dc:contributor>Voccia, Maria</dc:contributor>
    <void:sparqlEndpoint rdf:resource="http://localhost/fuseki/dspace/sparql"/>
    <dc:contributor>Mecking, Stefan</dc:contributor>
    <dc:creator>Caporaso, Lucia</dc:creator>
    <dcterms:rights rdf:resource="http://creativecommons.org/licenses/by/4.0/"/>
    <dc:contributor>Caporaso, Lucia</dc:contributor>
    <bibo:uri rdf:resource="https://kops.uni-konstanz.de/handle/123456789/58260"/>
    <dcterms:title>Mechanistic Insights into Ni(II)-Catalyzed Nonalternating Ethylene-Carbon Monoxide Copolymerization</dcterms:title>
    <dcterms:issued>2022-08-24</dcterms:issued>
    <foaf:homepage rdf:resource="http://localhost:8080/"/>
    <dc:creator>Mecking, Stefan</dc:creator>
    <dcterms:hasPart rdf:resource="https://kops.uni-konstanz.de/bitstream/123456789/58260/1/Voccia_2-vh0fd0j3xnf71.pdf"/>
    <dcterms:available rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2022-08-10T08:22:46Z</dcterms:available>
    <dc:rights>Attribution 4.0 International</dc:rights>
    <dc:creator>Falivene, Laura</dc:creator>
    <dc:creator>Voccia, Maria</dc:creator>
    <dc:creator>Lin, Fei</dc:creator>
    <dc:contributor>Lin, Fei</dc:contributor>
    <dcterms:abstract xml:lang="eng">Polyethylene materials with in-chain-incorporated keto groups were recently enabled by nonalternating copolymerization of ethylene with carbon monoxide in the presence of Ni(II) phosphinephenolate catalysts. We elucidate the mechanism of this long-sought-for reaction by a combined theoretical DFT study of catalytically active species and the experimental study of polymer microstructures formed in pressure-reactor copolymerizations with different catalysts. The pathway leading to the desired nonalternating incorporation proceeds via the cis/trans isomerization of an alkyl-olefin intermediate as the rate-determining step. The formation of alternating motifs is determined by the barrier for the opening of the six-membered C,O-chelate by ethylene binding as the decisive step. An η2-coordination of a P-bound aromatic moiety axially oriented to the metal center is a crucial feature of these Ni(II) catalysts, which also modulates the competition between the two pathways. The conformational constraints imposed in a 2',6'-dimethoxybiphenyl moiety overall result in a desirable combination of disfavoring ethylene coordination along the alternating incorporation pathway, which is primarily governed by electronics, while not overly penalizing the nonalternating chain growth, which is primarily governed by sterics.</dcterms:abstract>
    <dc:contributor>Baur, Maximilian</dc:contributor>
    <dcterms:isPartOf rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/29"/>
    <dc:creator>Baur, Maximilian</dc:creator>
  </rdf:Description>
</rdf:RDF>

Universitätsbibliographie

Ja

Begutachtet

Ja