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Catalytic Asymmetric Synthesis of Cyclohexanes by Hydrogen Borrowing Annulations.

ABSTRACT: Hydrogen borrowing catalysis serves as a powerful alternative to enolate alkylation, enabling the direct coupling of ketones with unactivated alcohols. However, to date, methods that enable control over the absolute stereochemical outcome of such a process have remained elusive. Here we report a catalytic asymmetric method for the synthesis of enantioenriched cyclohexanes from 1,5-diols via hydrogen borrowing catalysis. This reaction is mediated by the addition of a chiral iridium(I) complex, which is able to impart high levels of enantioselectivity upon the process. A series of enantioenriched cyclohexanes have been prepared and the mode of enantioinduction has been probed by a combination of experimental and DFT studies.

SUBMITTER: Armstrong RJ

PROVIDER: S-EPMC6771629 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Catalytic Asymmetric Synthesis of Cyclohexanes by Hydrogen Borrowing Annulations.

Armstrong Roly J RJ Akhtar Wasim M WM Young Tom A TA Duarte Fernanda F Donohoe Timothy J TJ

Angewandte Chemie (International ed. in English) 20190807 36

Hydrogen borrowing catalysis serves as a powerful alternative to enolate alkylation, enabling the direct coupling of ketones with unactivated alcohols. However, to date, methods that enable control over the absolute stereochemical outcome of such a process have remained elusive. Here we report a catalytic asymmetric method for the synthesis of enantioenriched cyclohexanes from 1,5-diols via hydrogen borrowing catalysis. This reaction is mediated by the addition of a chiral iridium(I) complex, wh ...[more]

PMID: 31265208

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