Mild and efficient molybdenum-mediated Pauson-Khand-type reaction.

Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
Organic Letters (Impact Factor: 6.14). 03/2005; 7(3):431-4. DOI: 10.1021/ol047678u
Source: PubMed

ABSTRACT [reaction: see text] The molybdenum-mediated Pauson-Khand reaction promoted by Mo(CO)3(DMF)3 takes place under very mild conditions in the absence of any promoter. High yields in Pauson-Khand adducts are obtained in the cyclization of a wide variety of functionalized 1,6- and 1,7-enynes. Enynes bearing electron withdrawing groups at the alkene terminus are particularly good substrates.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Organocobalt compounds in organic synthesis have three characteristic reactions. The first occurs because cobalt has a high affinity to carbon–carbon π-bonds or carbon–nitrogen π-bonds. The second occurs because cobalt has a high affinity to carbonyl groups. The third is due to cobalt easily tending to form square-planar bipyramidal six-coordination structures with four nitrogen atoms or two nitrogen atoms and two oxygen atoms at the square-planar position, and to bond with one or two carbon atoms at the axial position. The first characteristic reactions are the representative reactions of organocobalt compounds with a mutually bridged bond between the two π-bonds of acetylene and the cobalt–cobalt bond of hexacarbonyldicobalt. These are reactions with a Co2(CO)6 protecting group to reactive acetylene bond, the Nicholas reactions, the Pauson–Khand reactions ([2 + 2 + 1] cyclizations), [2 + 2 + 2] cyclizations, etc. These reactions are applied for the syntheses of many kinds of pharmaceutically useful compounds. The second reactions are carbonylations that have been used or developed as industrial processes such as hydroformylation for the manufacture of isononylaldehyde, and carbonylation for the production of phenylacetic acid from benzyl chloride. The third reactions are those reactions with the B12-type catalysts, and they have recently been used in organic syntheses and are utilized as catalysts for stereoselective syntheses. These reactions have been used as new applications for organic syntheses. Copyright © 2007 John Wiley & Sons, Ltd.
    Applied Organometallic Chemistry 04/2007; 21(5):318 - 344. · 2.01 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Tungsten and molybdenum catalysts were employed to promote the cyclisation of N-propargylic amides to afford the corresponding oxazolines or oxazines via 5-exo-dig or 6-endo-dig mode.
    Organic & Biomolecular Chemistry 05/2011; 9(12):4429-31. · 3.57 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Highly chemoselective and stereoselective tandem Pauson-Khand/[4+2] cycloaddition leads to efficient construction of the spirotricyclic core analogue of mangicol A.
    Chemical Communications 11/2012; · 6.38 Impact Factor