Synthesis of furan-3-carboxylic and 4-methylene-4,5-dihydrofuran-3-carboxylic esters by direct palladium iodide catalyzed oxidative carbonylation of 3-yne-1,2-diol derivatives

J Org Chem. 2012 Oct 5;77(19):8657-68. doi: 10.1021/jo301628n. Epub 2012 Sep 20.

Abstract

A variety of 3-yne-1,2-diol derivatives 1, bearing a primary or secondary alcoholic group at C-1, have been efficiently converted into high value added furan-3-carboxylic esters 2 in one step by PdI(2)/KI-catalyzed direct oxidative carbonylation, carried out in alcoholic media under relatively mild conditions (100 °C under 40 atm of a 4/1 mixture of CO and air). Carbonylated furans 2 were obtained in fair to excellent isolated yields (56-93%) through a sequential 5-endo-dig heterocyclization-alkoxycarbonylation-dehydration process, using only oxygen as the external oxidant. Under similar conditions, 2-methyl-3-yne-1,2-diols 3, bearing a tertiary alcoholic group, afforded 4-methylene-4,5-dihydrofuran-3-carboxylates 4 in satisfactory yields (58-70%).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkynes / chemistry*
  • Carboxylic Acids / chemistry*
  • Catalysis
  • Esters
  • Furans / chemical synthesis*
  • Furans / chemistry*
  • Iodides / chemistry*
  • Methane / analogs & derivatives*
  • Methane / chemistry
  • Molecular Structure
  • Oxidation-Reduction
  • Palladium / chemistry*

Substances

  • Alkynes
  • Carboxylic Acids
  • Esters
  • Furans
  • Iodides
  • carbene
  • Palladium
  • Methane