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Formation of Nucleophilic Allylboranes from Molecular Hydrogen and Allenes Catalyzed by a Pyridonate Borane that Displays Frustrated Lewis Pair Reactivity.

ABSTRACT: Here we report the in situ generation of nucleophilic allylboranes from H₂ and allenes mediated by a pyridonate borane that displays frustrated-Lewis-pair reactivity. Experimental and computational mechanistic investigations reveal that upon H₂ activation, the covalently bound pyridonate substituent becomes a datively bound pyridone ligand. Dissociation of the formed pyridone borane complex liberates Piers borane and enables a hydroboration of the allene. The allylboranes generated in this way are reactive towards nitriles. A catalytic protocol for the formation of allylboranes from H₂ and allenes and the allylation of nitriles has been devised. This catalytic reaction is a conceptually new way to use molecular H₂ in organic synthesis.

SUBMITTER: Hasenbeck M

PROVIDER: S-EPMC7814673 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Formation of Nucleophilic Allylboranes from Molecular Hydrogen and Allenes Catalyzed by a Pyridonate Borane that Displays Frustrated Lewis Pair Reactivity.

Hasenbeck Max M Ahles Sebastian S Averdunk Arthur A Becker Jonathan J Gellrich Urs U

Angewandte Chemie (International ed. in English) 20201022 52

Here we report the in situ generation of nucleophilic allylboranes from H<sub>2</sub> and allenes mediated by a pyridonate borane that displays frustrated-Lewis-pair reactivity. Experimental and computational mechanistic investigations reveal that upon H<sub>2</sub> activation, the covalently bound pyridonate substituent becomes a datively bound pyridone ligand. Dissociation of the formed pyridone borane complex liberates Piers borane and enables a hydroboration of the allene. The allylboranes g ...[more]

PMID: 32926511

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