Asymmetric Oxidative Cation/Olefin Cyclization of Polyenes: Evidence for Reversible Cascade Cyclization

Abstract

Platinum and silver work together: Activation of [(xylyl-phanephos)PtCl2] by silver generates an electrophilic catalyst that can enantioselectively, diastereoselectively, and regioselectively promote the stereospecific oxidative cyclization of polyene-ols (see scheme; Tr=trityl). Mechanistic experiments indicate that the stereochemistry-determining step is not the initial cyclization step, but rather a subsequent step in the reaction. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2008/z801423_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.