A Biomimetic Chromanol Cyclization Leading to α‐Tocopherol

Abstract

Vitamin E synthesis: Covalently linked dipeptides serve as readily removable and recyclable chiral auxiliaries in the diastereoselective cyclization of phytylhydroquinones. Depending on the chirality of the handle, (2R)- or (2S)-α-tocopherol (vitamin E) can be produced with a diastereomeric excess of up to 80 % (see scheme). Supporting information for this article, including spectroscopic data of 5, 6, 13, 18, and 22-pTsOH, is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2006/z503123_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.