Building Up Quarternary Stereocenters of Chromans by Asymmetric Redox Organocatalysis: A New Entry to Vitamin E. Issue 52 (13th November 2014)

• Record Type: Journal Article
• Authors: Netscher, Thomas
• Is Part Of: Angewandte Chemie international edition. Volume 53:Issue 52(2014)
• Page Start: 14313
• Page End: 14315
• Publication Date: 2014-11-13
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201409826
• Languages: English
• ISSNs: 1433-7851

Abstract

<abstract abstract-type="graphical" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p> <bold>High‐turnover catalysis</bold> offers a novel concept for the efficient chemo‐ and enantioselective preparation of chroman intermediates, which are useful for the synthesis of tocopherols (vitamin E components) and other biologically active compounds. A chiral ammonium iodide catalyst mediates the cycloetherification in combination with a cooxidant and an inorganic base in excellent yield and up to 93 % <italic>ee.</italic> OTs=<italic>para</italic>‐toluenesulfonyl.<boxed-text content-type="graphic" position="anchor" orientation="portrait"><graphic position="anchor" mimetype="image" xlink:href="ark:/27927/pgh2t6k4c1c" orientation="portrait" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /></boxed-text></p> </abstract>