Journal ArticleDOI
New ligands double the scope of the catalytic asymmetric dihydroxylation of olefins
K. Barry Sharpless,Willi Amberg,Matthias Beller,Hou Chen,Jens Hartung,Yasuhiro Kawanami,Doris Lubben,Eric Manoury,Yasukazu Ogino,Tomoyuki Shibata,Tatsuzo Ukita +10 more
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Improved ligands render terminal olefins good substrates for the osmium-catalyzed asymmetric dihydroxylation (ADH) process as discussed by the authors.Abstract:
Improved ligands render terminal olefins good substrates for the osmium-catalyzed asymmetric dihydroxylation (ADH) process, and the amounts of chiral ligand and osmium catalyst required diminish dramaticallyread more
Citations
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Journal ArticleDOI
Total synthesis of the immunosuppressants myriocin and 2-epi-myriocin.
TL;DR: The key transformations are the efficient synthesis of a quaternary (E)-vinyl Glycine by asymmetric deconjugative alkylation of a dehydroamino acid and an unusually highly diastereoselective dihydroxylation of the vinylglycine alkene.
Journal ArticleDOI
Heterogeneous enantioselective dihydroxylation of aliphatic olefins : a comparison between different polymeric cinchona alkaloid derivatives
TL;DR: In this article, two new polymeric cinchona alkaloid derived ligands were synthetized and used in the asymmetric dihydroxylation of aliphatic olefins, obtaining for the first time in the reaction performed in the heterogeneous phase enantioselectivity up to 88%.
Journal ArticleDOI
Modified cinchona alkaloid ligands: Improved selectivities in the osmium tetroxide catalyzed asymmetric dihydroxylation (AD) of terminal olefins
Mark P. Arrington,Youssef L. Bennani,Thomas Göbel,Patrick J. Walsh,Shu-Hai Zhao,K. Barry Sharpless +5 more
TL;DR: In this paper, the quinuclidine and quinoline moieties of the bis cinchona-alkaloid phthalazine ligands were modified to improve enantioselectivities in the osmium tetroxide catalyzed dihydroxylation of olefins.
Journal ArticleDOI
A General Method for the Synthesis of Bastaranes and Isobastaranes: First Total Synthesis of Bastadins 5, 10, 12, 16, 20, and 21
TL;DR: A general strategy for the synthesis of twenty naturally occurring bastadins (all but bastadin 3) is presented and four bastaranes and two isobastaranes were synthesized as a demonstration of the flexibility and efficiency of the approach presented.
Book ChapterDOI
Cinchona Alkaloids-Derivatives and Applications.
TL;DR: The introduction discusses in short conformational equilibria, traditional separation scheme, biosynthesis, and de novo chemical syntheses useful chemical applications of the alkaloids as chiral recognition agents and effective chiral catalysts.
References
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Journal ArticleDOI
Nuclear magnetic resonance enantiomer regents. Configurational correlations via nuclear magnetic resonance chemical shifts of diastereomeric mandelate, O-methylmandelate, and .alpha.-methoxy-.alpha.-trifluoromethylphenylacetate (MTPA) esters
James A. Dale,Harry S. Mosher +1 more
PatentDOI
First practical method for asymmetric epoxidation
Tsutomu Katsuki,K. B. Sharpless +1 more
TL;DR: In this article, a metal alkoxide is used as a catalyst, where the metal has a coordination number of at least four, and at least one, usually two, of the alkoxide groups bonded to the metal are bonded to asymmetric carbon atoms.
Journal ArticleDOI
Asymmetric dihydroxylation via ligand-accelerated catalysis
TL;DR: Dihydroxylation asymetrique de composes ethyleniques du type styrene, vinylcyclohexane, hexene-3 en les glycols correspondants as mentioned in this paper.
Journal ArticleDOI
Asymmetric induction in the reaction of osmium tetroxide with olefins
Journal ArticleDOI
An improved synthesis of the taxol side chain and of RP 56976
TL;DR: In this paper, the methode presentee se fait au depart de phenyl-3 dihydroxy-2,3 propionate de methyle via epoxydation, et d'azoture de sodium.