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A Dinuclear Mechanism Implicated in Controlled Carbene Polymerization.

ABSTRACT: Carbene polymerization provides polyolefins that cannot be readily prepared from olefin monomers; however, controlled and living carbene polymerization has been a long-standing challenge. Here we report a new class of initiators, (π-allyl)palladium carboxylate dimers, which polymerize ethyl diazoacetate, a carbene precursor in a controlled and quasi-living manner, with nearly quantitative yields, degrees of polymerization >100, molecular weight dispersities 1.2-1.4, and well-defined, diversifiable chain ends. This method also provides block copolycarbenes that undergo microphase segregation. Experimental and theoretical mechanistic analysis supports a new dinuclear mechanism for this process.

SUBMITTER: Zhukhovitskiy AV

PROVIDER: S-EPMC6615555 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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A Dinuclear Mechanism Implicated in Controlled Carbene Polymerization.

Zhukhovitskiy Aleksandr V AV Kobylianskii Ilia J IJ Thomas Andy A AA Evans Austin M AM Delaney Connor P CP Flanders Nathan C NC Denmark Scott E SE Dichtel William R WR Toste F Dean FD

Journal of the American Chemical Society 20190409 16

Carbene polymerization provides polyolefins that cannot be readily prepared from olefin monomers; however, controlled and living carbene polymerization has been a long-standing challenge. Here we report a new class of initiators, (π-allyl)palladium carboxylate dimers, which polymerize ethyl diazoacetate, a carbene precursor in a controlled and quasi-living manner, with nearly quantitative yields, degrees of polymerization >100, molecular weight dispersities 1.2-1.4, and well-defined, diversifiab ...[more]

PMID: 30964670

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