Heck reaction



The Heck reaction (also called the Mizoroki-Heck reaction) is the chemical reaction of an unsaturated catalyst to form a substituted alkene.[1][2]

The reaction is performed in the presence of an sodium acetate.

Several reviews have been published.[3][4][5]

This naphthalene compound with ethylene:

Reaction mechanism

The catalytic cycle for the Heck reaction involves a series of transformations around the palladium catalyst. The palladium(0) compound required in this cycle is generally prepared in situ from a palladium(II) precursor.[6]

For instance, Wacker process.

This cycle is not limited to vinyl compounds, in the Negishi coupling between aryl halides and organozinc compounds. Platinum forms strong bonds with carbon and does not have a catalytic activity in this type of reaction.

Variations

Ionic liquid Heck reaction

In the presence of an silica gel [7]. In this way the reaction proceeds in water and the catalyst is re-usable.

Heck oxyarylation

In the Heck oxyarylation modification the palladium substituent in the syn-addition intermediate is displaced by a hydroxyl group and the reaction product contains a tetrahydrofuran ring.[8]

Amino-Heck reaction

In the amino-Heck reaction a triethylamine.

References

  1. ^  Palladium-catalyzed vinylic hydrogen substitution reactions with aryl, benzyl, and styryl halides Heck, R. F.; Nolley, Jr., J. P. J. Org. Chem. 1972, 37(14), 2320-2322. (doi:10.1021/jo00979a024)
  2. ^  Mizoroki, T.; Mori, K.; Ozaki, A. Bull. Chem. Soc. Jap. 1971, 44, 581.
  3. ^  Heck, R. F. Org. React. 1982, 27, 345-390. (Review)
  4. ^  Fine Feathers Make Fine Birds: The Heck Reaction in Modern Garb A. de Meijere, F. E. Meyer, Jr.; Angew. Chem. Int. Ed. Engl. 1994, 33(23-24), 2379–2411. (Review)
  5. ^  Belestskaya, I. P.; Cheprakov, A. V. Chem. Rev. 2000, 100, 3009–3066. (Review, doi:10.1021/cr9903048)
  6. ^  Ozawa, F.; Kubo, A.; Hayashi, T. Chemistry Lett. 1992, 2177–2180.
  7. ^  Sustainable Mizoroki–Heck reaction in water: remarkably high activity of Pd(OAc)2 immobilized on reversed phase silica gel with the aid of an ionic liquid Chemical Communications, 2005, (23), 2942 - 2944. (Abstract)
  8. ^  Further insight into the mechanism of Heck oxyarylation in the presence of chiral ligands Lorand Kiss, Tibor Kurtan, Sandor Antus, Henri Brunner Arkivoc GB-653J 2003 (Online Article)
  9. ^  Palladium(0)-catalyzed synthesis of pyridines from β-acetoxy-γ,δ-unsaturated ketone oximes Mitsuru Kitamura, Daisuke Kudo, and Koichi Narasaka Arkivoc JC-1563E 2005 (Online article)

See also

 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Heck_reaction". A list of authors is available in Wikipedia.