Gatterman-Koch synthesis

Gatterman-Koch synthesis org chem A synthesis of aldehydes aldehydes form when an aromatic hydrocarbon is heated in the presence of hydrogen chloride, certain metallic chloride catalysts, and either carbon monoxide or hydrogen cyanide. gad-3r-man kok, sin-th3-s3s ... 

Show how you would use the Friedel-Crafts acylation, Clemmensen reduction, and/or Gatterman-Koch synthesis to prepare the following compounds ... 

The Gatterman-Koch synthesis is a variant of the Friedel-Crafts acylation in which carbon monoxide and HC1 generate an intermediate that reacts like formyl chloride. Like Friedel-Crafts reactions, the Gatterman-Koch formylation succeeds only with benzene and activated benzene derivatives. 

Gatterman-Koch synthesis The synthesis of benzaldehydes by treating a benzene derivative with CO and HQ using an AlCly/CuCI catalyst, (p. 779)... 

Aldehydes cannot be synthesized by the Friedel-Crafts reaction using methanoyl chloride (formyl chloride) because it is an unstable compound. However, a gaseous mixture of carbon monoxide and hydrogen chloride reacts like formyl chloride. The formylation of an aromatic compound using this gaseous mixture and aluminum trichloride is called the Gatterman—Koch synthesis. Like the Friedel-Crafts reaction, this method is limited to activated aromatic compounds. 

GATTERMAN - KOCH Cartionylation Synthesis of aromatic aldehydes or ketones using cyanide salts or CO - HCI and Lewis adds. 

The Gatterman aldehyde synthesis employs hydrogen cyanide and unlike the Gatterman-Koch procedure, this method is successful in the case of phenols and phenolic ethers, although only the more reactive hydrocarbons are formylated... 

Another commercial aldehyde synthesis is the catalytic dehydrogenation of primary alcohols at high temperature in the presence of a copper or a copper-chromite catalyst. Although there are several other synthetic processes employed, these tend to be smaller scale reactions. For example, acyl halides can be reduced to the aldehyde (Rosemnund reaction) using a palladium-on-barium sulfate catalyst. Formylation of aryl compounds, similar to hydrofomiylation, using HCN and HQ (Gatterman reaction) or carbon monoxide and HQ (Gatterman-Koch reaction) can be used to produce aromatic aldehydes. 

Gabriel synthesis, 403 Gatterman reaction, 429 Gatterman-Koch reaction, 307 Gauche conformation, 53, 170, 275 Geometric isomerism, 88 ... 

Barbier-Wieland degradation Boudroux-Chichibabin synthesis Bouveault aldehyde synthesis Darzens synthesis Friedel-Crafts Reaction Gatterman-Koch reaction Grignard reaction Reformatsky reaction Saytzeff reaction Ullmann coupling reaction Wiirtz coupling reaction Wiirtz-Fittig reaction... 

The synthesis of benzaldehyde from benzene poses a problem because formyl chloride, the acyl halide required for the reaction, is unstable and cannot be purchased. Formyl chloride can be prepared, however, by means of the Gatterman-Koch formyla-tion reaction. This reaction uses a high-pressure mixture of carbon monoxide and HCl to generate formyl chloride, along with an aluminum chloride-cuprous chloride catalyst to carry out the acylation reaction. 

Thermodynamics can also be usefully employed in analyzing the role of a catalyst in organic synthesis. A typical example is the Gatterman-Koch reaction. 

This reaction is related to the Ciamician-Dennstedt Reaction, Duff Reaction, Gatterman Aldehyde Synthesis, and Gattermann-Koch Formylation. 

Stull, Westrum, and Sinke devote a chapter to the discussion of the applications of thermodynamics to industrial problems. Subjects covered include the petroleum industry, chemicals from methane, styrene manufacture, acrylonitrile and vinyl chloride syntheses, methanol synthesis, formaldehyde production from methanol, acetic acid manufacture, the Gatterman-Koch reaction, and catalyst selection. 

---