• Media type: E-Article
  • Title: Synthesis of 4‐Hydroxy‐5‐methyl‐ and 4‐Hydroxy‐6‐methylcyclohexenones by PdII‐Catalyzed Oxidation and Lipase‐Catalyzed Hydrolysis
  • Contributor: Meister, Anne C.; Nieger, Martin; Bräse, Stefan
  • imprint: Wiley, 2012
  • Published in: European Journal of Organic Chemistry
  • Language: English
  • DOI: 10.1002/ejoc.201200704
  • ISSN: 1434-193X; 1099-0690
  • Keywords: Organic Chemistry ; Physical and Theoretical Chemistry
  • Origination:
  • Footnote:
  • Description: <jats:title>Abstract</jats:title><jats:p>A short route for the syntheses of methyl‐substituted hydroxycyclohexenones, which are building blocks for various natural products, is presented. Both oxygen atoms were introduced as acetates by a palladium(II)‐catalyzed 1,4‐addition to a 1,3‐diene. The distinction between the two acetoxy groups was achieved by regioselective monohydrolysis with lipase from <jats:italic>Candida rugosa</jats:italic>, which gave 1‐acetoxy‐4‐hydroxy‐5‐methylcyclohexene and its 6‐methyl regioisomer as a separable mixture. The target compounds 4‐hydroxy‐5‐methylcyclohex‐2‐enone and 4‐hydroxy‐6‐methylcyclohex‐2‐enone could then be obtained as diastereomeric mixtures in good overall yields and with moderate enantiomeric excesses (31–67 %).</jats:p>