Highly diastereoselective Diels-Alder reactions with (R)-ethoxy p-tolyl vinyl sulfonium tetrafluoroborate
TL;DR: In this article, a Tolyl vinyl sulfoxide has been efficiently activated for Diels-Alder reactions by transformation into a sulfonium salt 3a or by addition of TMSOTf.
Abstract: p-Tolyl vinyl sulfoxide has been efficiently activated for Diels-Alder reactions by transformation into a sulfonium salt 3a or by addition of TMSOTf. Very high diastereomeric excesses have been achieved (>98%) at −20°C in many cases. Best results have been obtained with cyclopentadiene, furan and 2,3-dimethyl-1,3-butadiene. In this way enantiomerically pure oxanorbornenone 19a has been prepared. The reaction mechanism is briefly discussed.
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TL;DR: In this article, the authors present a method for the synthesis of Intramolecular Diels-Alder Reactions of Furans 3.1.3.3 Synthetic targets 3.2.
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TL;DR: In this article, the progress made in the chemistry, synthesis and biology of carbasugars until May 2004 is discussed, including the extensively studied carbapyranoses as well as the scarcely considered carbafuranoses.
Abstract: This review covers the progress made in the chemistry, synthesis and biology of carbasugars until May 2004. It includes the extensively studied carbapyranoses as well as the scarcely considered carbafuranoses. Specific topics discussed include the natural occurrence of carbasugars, biosynthesis and biological activity of carbasugars, conformational analysis of carbasugars, and the compilation of synthetic methods of carbafuranoses and carbapyranoses.
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TL;DR: In this article, Diels-alder-reaction and opening metathesis polymerization are used for diastereoselective bis-hydroxylation and total synthesis.
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TL;DR: In this article, a chiral catalyst or reagent may be used to create an asymmetric center on the components of a racemic mixture, and the quantitative relationships between the various experimental data (ee's, fractional amounts of products, conversion) are given, and extended to the formation of regioisomeric products.
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TL;DR: In this paper, the authors presented a method for constructing a chim organ from the chim organ of the LSA's International Chim Organ Association (LSA-ARTICLE-1984-009).
Abstract: Note: Univ lausanne,inst chim organ,ch-1005 lausanne,switzerland Reference LGSA-ARTICLE-1984-009doi:101002/hlca19840670629 Record created on 2005-11-09, modified on 2017-05-12
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