Unexpected solvent-free cycloadditions of 1,3-cyclohexanediones to 1-(pyridin-2-yl)-enones mediated by manganese(III) acetate in a ball mill

J Org Chem. 2008 Sep 19;73(18):7088-95. doi: 10.1021/jo800870z. Epub 2008 Aug 19.

Abstract

Under solvent-free ball-milling conditions, manganese(III) acetate dihydrate-mediated cycloadditions of 5,5-dimethyl-1,3-cyclohexanedione and 1,3-cyclohexanedione to various 1-(pyridin-2-yl)-enones proceeded efficiently to afford trans-2-acyl-3-aryl/alkyl-2,3,6,7-tetrahydro-4(5H)-benzofuranone derivatives. The cyclization reactions exhibited good to excellent yields, as well as extremely high diastereoselectivity and unexpected regioselectivity. Manganese(III) acetate behaved both as an oxidant and as a Lewis acid.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetates / chemistry*
  • Cyclization
  • Cyclohexanones / chemistry*
  • Molecular Structure
  • Organometallic Compounds / chemistry*
  • Oxidants / chemistry
  • Oxidation-Reduction
  • Pyridones / chemical synthesis*
  • Pyridones / chemistry
  • Solvents
  • Stereoisomerism

Substances

  • 1-(pyridin-2-yl)-enone
  • Acetates
  • Cyclohexanones
  • Organometallic Compounds
  • Oxidants
  • Pyridones
  • Solvents
  • manganese(III) acetate dihydrate
  • 1,3-cyclohexanedione