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Nonclassical Mechanism in the Cyclodehydration of Diols Catalyzed by a Bifunctional Iridium Complex.

ABSTRACT: 1,4- and 1,5-diols undergo cyclodehydration upon treatment with cationic N-heterocyclic carbene (NHC)-Ir^III complexes to give tetrahydrofurans and tetrahydropyrans, respectively. The mechanism was investigated, and a metal-hydride-driven pathway was proposed for all substrates, except for very electron-rich ones. This contrasts with the well-established classical pathways that involve nucleophilic substitution.

SUBMITTER: Gonzalez Miera G

PROVIDER: S-EPMC7379557 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Nonclassical Mechanism in the Cyclodehydration of Diols Catalyzed by a Bifunctional Iridium Complex.

González Miera Greco G Bermejo López Aitor A Martínez-Castro Elisa E Norrby Per-Ola PO Martín-Matute Belén B

Chemistry (Weinheim an der Bergstrasse, Germany) 20190123 10

1,4- and 1,5-diols undergo cyclodehydration upon treatment with cationic N-heterocyclic carbene (NHC)-Ir<sup>III</sup> complexes to give tetrahydrofurans and tetrahydropyrans, respectively. The mechanism was investigated, and a metal-hydride-driven pathway was proposed for all substrates, except for very electron-rich ones. This contrasts with the well-established classical pathways that involve nucleophilic substitution. ...[more]

PMID: 30475410

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