Gatterman—Koch reaction

Gasoline, manufacture of, 99-100 octane number of, 100 Gatterman-Koch reaction. 596 Gauche conformation, 95 butane and, 95-96 steric strain in, 96... 

Another method, formylation with CO and HCl in the presence of AICI3 and CuCl (the Gatterman-Koch reaction), is limited to benzene and alkylbenzenes. ... 

The decarbonylation of aromatic aldehydes with sulfuric acid" is the reverse of the Gatterman-Koch reaction (11-16). It has been carried out with trialkyl- and trialkoxybenzaldehydes. The reaction takes place by the ordinary arenium ion mechanism the attacking species is H and the leaving group is HCO, which can lose a proton to give CO or combine with OH from the water solvent to give formic acid." Aromatic aldehydes have also been decarbonylated with basic catalysts." When basic catalysts are used, the mechanism is probably similar to the SeI process of 11-38. See also 14-39. 

This reaction is known as Gatterman-Koch reaction. 

Arenes can be formylated by generating the active intermediate, CfeC—H, from reagents other than HCOCl. The Gatterman-Koch reaction uses a high-pressure gaseous mixture of CO and HCl. 

Gatterman-Koch Reaction (see under Gatterman Reaction)... 

Aromatic aldehydes may be obtained by passing a mixture of carbon monoxide and hydrogen chloride into the aromatic hydrocarbon in the presence of a mixture of copper(i) chloride and aluminium chloride which acts as a catalyst (Gatterman-Koch reaction). It is probable that the electrophilic species is the ... 

This reaction, known as the Gatterman-Koch reaction, does not work with phenolic or amino aromatic species due to complex formation with the Lewis acid. It does work well with aromatic hydrocarbons and is used industrially to prepare benzaldehyde and, as here, p-tolualdehyde. 

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. 

The formyl cation HCO+ (vco at 2110 cm ) is generated from CO under pressure in the presence of HF/SbFs. Concentrated sulfuric acid or the HCl/CuCl system, activates carbon monoxide toward the electrophilic attack on aromatic hydrocarbons to form aromatic aldehydes (Gatterman-Koch reaction). Branched carboxylic acids are obtained from alkenes and CO in the presence of concentrated sulfuric acid (Koch process) (equation 3). ... 

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

CuCl" (the Gatterman—Koch reaction), is hmited to benzene and alkylben-... 

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... 

In the Gatterman-Koch reaction, a formyl group (-CHO) is introduced directly onin a benzene ring. For example, reaction of toluene with CO and HCI in the presenc of mixed CuCl/AlClg gives p-metbylbenzaldehyde. Propose a mechanism. 

Gatterman-Koch reaction The reaction of an aromatic molecule with CO and HC1 to give an aromatic aldehyde, in the presence of A1C13 and CuCl. 

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