• Media type: E-Article
  • Title: A Combined Vinylogous Mannich/Diels–Alder Approach for the Stereoselective Synthesis of Highly Functionalized Hexahydroindoles
  • Contributor: Ruff, Bettina M.; Zhong, Sabilla; Nieger, Martin; Sickert, Marcel; Schneider, Christoph; Bräse, Stefan
  • imprint: Wiley, 2011
  • Published in: European Journal of Organic Chemistry
  • Language: English
  • DOI: 10.1002/ejoc.201100996
  • ISSN: 1434-193X; 1099-0690
  • Keywords: Organic Chemistry ; Physical and Theoretical Chemistry
  • Origination:
  • Footnote:
  • Description: <jats:title>Abstract</jats:title><jats:p>A versatile strategy for the formation of hydroindole derivatives is reported. The molecules synthesized are highly functionalized and bear up to six stereogenic centers. We were able to develop a stereoselective route starting from nonchiral commercially available materials. Key steps in the formation of the bicyclic products are an organocatalytic vinylogous Mukaiyama–Mannich and a Diels–Alder reaction. The former uses a 1,1′‐bi‐2‐napthol (BINOL)‐based chiral Brønsted acid catalyst to build the first stereogenic center. The [4+2] cycloaddition proceeds highly diastereoselectively and furnishes one main stereoisomer, which represents the scaffold of the mycotoxins Rostratin B–D. Other transformations include iodolactonization, a Curtius rearrangement, additions, oxidations, and reductions.</jats:p>