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Polymerization of Allenes by Using an Iron(II) β-Diketiminate Pre-Catalyst to Generate High M_n Polymers.

ABSTRACT: Herein, we report an iron(II)-catalyzed polymerization of arylallenes. This reaction proceeds rapidly at room temperature in the presence of a hydride co-catalyst to generate polymers of weight up to M_n =189 000 Da. We have determined the polymer structure and chain length for a range of monomers through a combination of NMR, differential scanning calorimetry (DSC) and gel permeation chromatography (GPC) analysis. Mechanistically, we postulate that the co-catalyst does not react to form an iron(II) hydride in situ, but instead the chain growth is proceeding via a reactive Fe(III) species. We have also performed kinetic and isotopic experiments to further our understanding. The formation of a highly unusual 1,3-substituted cyclobutane side-product is also investigated.

SUBMITTER: Woof CR

PROVIDER: S-EPMC8457186 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Polymerization of Allenes by Using an Iron(II) β-Diketiminate Pre-Catalyst to Generate High Mn Polymers.

Woof Callum R CR Durand Derek J DJ Webster Ruth L RL

Chemistry (Weinheim an der Bergstrasse, Germany) 20210716 48

Herein, we report an iron(II)-catalyzed polymerization of arylallenes. This reaction proceeds rapidly at room temperature in the presence of a hydride co-catalyst to generate polymers of weight up to Mn =189 000 Da. We have determined the polymer structure and chain length for a range of monomers through a combination of NMR, differential scanning calorimetry (DSC) and gel permeation chromatography (GPC) analysis. Mechanistically, we postulate that the co-catalyst does not react to fo ...[more]

PMID: 34143554

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