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Hydroarylation of olefins catalysed by a dimeric ytterbium(II) alkyl.

ABSTRACT: Although the nucleophilic alkylation of aromatics has recently been achieved with a variety of potent main group reagents, all of this reactivity is limited to a stoichiometric regime. We now report that the ytterbium(II) hydride, [BDI^DippYbH]₂ (BDI^Dipp = CH[C(CH₃)NDipp]₂, Dipp = 2,6-diisopropylphenyl), reacts with ethene and propene to provide the ytterbium(II) n-alkyls, [BDI^DippYbR]₂ (R = Et or Pr), both of which alkylate benzene at room temperature. Density functional theory (DFT) calculations indicate that this latter process operates through the nucleophilic (S_N2) displacement of hydride, while the resultant regeneration of [BDI^DippYbH]₂ facilitates further reaction with ethene or propene and enables the direct catalytic (anti-Markovnikov) hydroarylation of both alkenes with a benzene C-H bond.

SUBMITTER: Richardson GM

PROVIDER: S-EPMC8149703 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Hydroarylation of olefins catalysed by a dimeric ytterbium(II) alkyl.

Richardson Georgia M GM Douair Iskander I Cameron Scott A SA Bracegirdle Joe J Keyzers Robert A RA Hill Michael S MS Maron Laurent L Anker Mathew D MD

Nature communications 20210525 1

Although the nucleophilic alkylation of aromatics has recently been achieved with a variety of potent main group reagents, all of this reactivity is limited to a stoichiometric regime. We now report that the ytterbium(II) hydride, [BDIDippYbH]2 (BDIDipp = CH[C(CH3)NDipp]2, Dipp = 2,6-diisopropylphenyl), reacts with ethene and propene to provide the ytterbium(II) n-alkyls, [BDIDippYbR]2 (R = Et or Pr), both of which alky ...[more]

PMID: 34035284

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