Catalytic Asymmetric Synthesis of Cyclohexanes by Hydrogen Borrowing Annulations. Issue 36 (7th August 2019)

• Record Type: Journal Article
• Authors: Armstrong, Roly J.; Akhtar, Wasim M.; Young, Tom A.; Duarte, Fernanda; Donohoe, Timothy J.
• Is Part Of: Angewandte Chemie international edition. Volume 58:Issue 36(2019)
• Page Start: 12558
• Page End: 12562
• Publication Date: 2019-08-07
• Subjects: asymmetric catalysis -- enantioselectivity -- hydrogen borrowing -- iridium; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201907514
• Languages: English
• ISSNs: 1433-7851

Abstract

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. Abstract : A catalytic asymmetric method is described for the synthesis of enantioenriched cyclohexanes from racemic 1, 5‐diols by hydrogen borrowing catalysis. This reaction is mediated by a chiral iridium(I) complex which is able to impart high levels of enantioselectivity to the process.