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Coordinative Chain Transfer Polymerization of Butadiene with Functionalized Aluminum Reagents.

ABSTRACT: Functionalized aluminum alkyls enable effective coordinative chain transfer polymerization with selective chain initiation by the functionalized alkyl. (ω-Aminoalkyl)diisobutylaluminum reagents (12 examples studied) obtained by hydroalumination of α-amino-ω-enes with diisobutylaluminum hydride promote the stereoselective catalytic chain growth of butadiene on aluminum in the presence of Nd(versatate)₃ , Cp*₂ Nd(allyl), or Cp*₂ Gd(allyl) precatalysts and [PhNMe₂ H⁺ ]/[B(C₆ F₅ )₄ ^- ]. Carbazolyl- and indolylaluminum reagents result in efficient molecular weight control and chain initiation by the aminoalkyl rather than the isobutyl substituent bound to aluminum. As confirmed for (3-(9H-carbazol-9-yl)propyl)-initiated polybutadiene (PBD), for example, by deuterium quenching studies, polymer chain transfer by β-hydride transfer is negligible in comparison to back-transfer to aluminum.

SUBMITTER: Gottker-Schnetmann I

PROVIDER: S-EPMC6899983 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Coordinative Chain Transfer Polymerization of Butadiene with Functionalized Aluminum Reagents.

Göttker-Schnetmann Inigo I Kenyon Philip P Mecking Stefan S

Angewandte Chemie (International ed. in English) 20191024 49

Functionalized aluminum alkyls enable effective coordinative chain transfer polymerization with selective chain initiation by the functionalized alkyl. (ω-Aminoalkyl)diisobutylaluminum reagents (12 examples studied) obtained by hydroalumination of α-amino-ω-enes with diisobutylaluminum hydride promote the stereoselective catalytic chain growth of butadiene on aluminum in the presence of Nd(versatate)3 , Cp*2 Nd(allyl), or Cp*2 Gd(allyl) precatalysts and [PhNMe<su ...[more]

PMID: 31571376

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Dataset Information

Coordinative Chain Transfer Polymerization of Butadiene with Functionalized Aluminum Reagents.

Publications

Coordinative Chain Transfer Polymerization of Butadiene with Functionalized Aluminum Reagents.

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