Gattermann reaction

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For the conversion of benzenediazonium chloride to a haloarene (also referred to as the 'Gattermann reaction'), see Diazonium compound#Gatterman reaction.

The Gattermann reaction, (also known as the Gattermann aldehyde synthesis) is a chemical reaction in which aromatic compounds are formylated by hydrogen cyanide in the presence of a Friedel–Crafts catalyst (e.g. AlCl3). It is named for the German chemist Ludwig Gattermann[1] and is similar to the Friedel-Crafts reaction.

Gattermann I.png
Gattermann II.png

The reaction can be simplified by replacing the HCN/AlCl3 combination with zinc cyanide.[2] Although it is also highly toxic, Zn(CN)2 is a solid, making it safer to work with than gaseous HCN;[3] additionally, because the reaction uses HCl, Zn(CN)2 also supplies the reaction with ZnCl2 in-situ, where it acts as a Lewis acid catalyst. Examples of Zn(CN)2 being used in this way include the synthesis of 2-Hydroxy-1-nafthaldehyde[2] and Mesitaldehyde.[4]

Gattermann–Koch reaction[edit]

The Gattermann–Koch reaction, named after the German chemists Ludwig Gattermann and Julius Arnold Koch,[5] refers to a Friedel–Crafts acylation reaction in which carbon monoxide, hydrochloric acid, and a Friedel–Crafts catalyst (e.g. AlCl3) are used to produce aromatic aldehydes from various aromatic compounds, including derivatives of benzene and naphthalene:[6]

Gattermann-Koch.svg

The applicability of the reaction includes many substituted aromatic derivatives, for example the conversion of toluene to p-tolualdehyde.[7] However, unlike the Gattermann reaction with HCN, this reaction is not applicable to phenol and phenol ether substrates.[3] Additionally, when Zinc chloride is used as the catalyst, the presence of traces of copper(I) chloride co-catalyst is often necessary.

See also[edit]

References[edit]

  1. ^ L. Gattermann, W. Berchelmann (1898). "Synthese aromatischer Oxyaldehyde". Berichte der deutschen chemischen Gesellschaft 31 (2): 1765–1769. doi:10.1002/cber.18980310281. 
  2. ^ a b Adams R., Levine I. (1923). "Simplification of the Gattermann Synthesis of Hydroxy Aldehydes". J. Am. Chem. Soc. 45 (10): 2373–77. doi:10.1021/ja01663a020. 
  3. ^ a b Adams, Roger (1957). Organic Reactions, Volume 9. New York: John Wiley & Sons, Inc. pp. 38 & 53–54. ISBN 9780471007265. Retrieved 18 July 2014. 
  4. ^ Fuson R. C., Horning E. C., Rowland S. P., Ward M. L. (1955), Mesitaldehyde, Org. Synth., doi:10.15227/orgsyn.023.0057 ; Coll. Vol. 3: 549 
  5. ^ Gattermann, L.; Koch, J. A. (1897). "Eine Synthese aromatischer Aldehyde". Ber. 30: 1622. doi:10.1002/cber.18970300288. 
  6. ^ LI Jie Jack (2003). Name Reactions: A Collection of Detailed Reaction Mechanisms (available on Google Books) (2nd ed.). Springer. p. 157. ISBN 3-540-40203-9. 
  7. ^ G. H. Coleman, David Craig (1943), p-Tolualdehyde, Org. Synth. ; Coll. Vol. 2: 583