Switching Catalysts for Choosing Products

  • Author: Asian Journal of Organic Chemistry
  • Published Date: 21 November 2013
  • Source / Publisher: Asian Journal of Organic Chemistry/Wiley-VCH
  • Copyright: Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
thumbnail image: Switching Catalysts for Choosing Products

The bis(trifluoromethanesulfonyl)methyl (Tf2CH; Tf = CF3SO2) group is a very strong acidic functionality that has an active hydrogen atom on an electronically neutral carbon atom. Hikaru Yanai and co-workers, Tokyo University of Pharmacy and Life Sciences, Japan, have developed two kinds of acid catalysts on the basis of this carbon acid.

The first one is a triple carbon acid that has three Tf2CH groups in the molecular structure (see picture above). This catalyst was used in the first example of an organocatalytic olefination of arene-fused lactones by reaction with a silicon enolate (see scheme below).

The second one is a zwitterion that contains a highly stabilized carbanion moiety, which is an intermolecular salt between Tf2CH functionality and aniline functionality. By using this zwitterion instead of the triple carbon acid, similar reactions to those conducted with the first catalyst gave aldol adducts in a selective manner (see scheme below). Furthermore, the adducts were successfully converted into highly substituted 1-naphthols, which are common in the structure of biologically active naphthalenes.

It is hoped that these findings on carbon-acid and zwitterion catalysis will provide the basis for the Tf2CH group to be a useful acidic functionality for molecular design of organocatalysts.

Article Views: 3959

Sign in Area

Please sign in below

Additional Sign In options

Please note that to comment on an article you must be registered and logged in.
Registration is for free, you may already be registered to receive, e.g., the newsletter. When you register on this website, please ensure you view our terms and conditions. All comments are subject to moderation.

Article Comments - To add a comment please sign in

If you would like to reuse any content, in print or online, from ChemistryViews.org, please contact us first for permission and consult our permission guidance prior to making your request

Follow on Facebook Follow on Twitter Follow on YouTube Follow on LinkedIn Follow on Instagram RSS Sign up for newsletters

Magazine of Chemistry Europe (16 European Chemical Societies) published by Wiley-VCH