Helmchen, Gunter

Submitted by Martin Kollmar, Richard Parlitz, Stephan R. Oevers, and Gunter Helmchen. ... 

Gunter Helmchen of the Universitat Heidelberg took advantage (Chem. Comm. 2004, 896) of the substitutional flexibility of It-allyl indium complexes to develop enantioselective cyclizations such as 3 to 4. Six-membered rings are also formed efficiently (88% ). 

Gunter Helmchen of the Ruprecht-Karls-Universitat, Heidelberg has reported Chem. Common. 2005,2957) the design of chiral ligands that direct the absolute sense of the Ir-catalyzed intramolecular alkylation of 4 to 5. Both 5- and 6-membered rings can be prepared in high using this procedure. The use of Ir, which is much less expensive than Pd or Rh, is particularly attractive. 

Vladimir Prelog, Gunter Helmchen Grundlagen des CIP-Systems und VorschlUge filr eine Revision, Angew. Chem. 94, 614-631 (1982) Angew. Chem. Int. Ed. Engl. 21, 567-583 (1982)... 

Gunter Helmchen Glossary of Problematic Terms in Organic Stereochemistry, Enantiomer 1(1), vier nicht numerierte Seiten nach S. 84 (1996)... 

Gunter Helmchen Nomenclature and Vocabulary of Organic Stereochemistry, in Methods of Organic Chemistry (Houben-Weyl), Volume E21a, Stereoselective Synthesis, Thieme, Stuttgart, New York, 1995, pp. 1-74... 

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