Reaction Aldehyde Synthesis. Gattermann-Koch

REACTION ALDEHYDE SYNTHESIS — GATTERMANN-KOCH Example p-Tolylaldehyde from Toluene and Carbon Monoxide1 

To 30 grammes of freshly distilled toluene (boiling-point no0) contained in a wide-necked vessel (an extract of beef jar is convenient) cooled with water, add, not too quickly, 45 grammes of pulverised, freshly prepared aluminium chloride and 5 grammes pure cuprous chloride (see page 355). The vessel is closed by a three-hole cork in the middle hole is inserted a glass tube which carries a stirrer (paddle wheel of glass) the other holes are used for the inlet and outlet tubes (Fig. 75). 

After the apparatus has been fastened firmly in a clamp it is immersed into a casserole filled with water at 200. A current, not too rapid, of carbon monoxide and hydrochloric acid gas is led in through the prong-shaped tube while the stirrer is set in motion (a small motor is convenient). 

Preparation of Carbon Monoxide In a round litre flask heat 100 grammes of crystallised oxalic acid with 600 grammes of concentrated sulphuric acid. The gases 

A direct synthesis of the aromatic aldehydes by means of the Friedel-Crafts reaction could not be brought about until recently, because of the instability of formyl chloride, which, if formed, decomposes immediately into carbon monoxide and hydrochloric add  

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Gattermann Aldehyde Synthesis Gattermann Reaction Gattermann-Koch Reaction Glaser Coupling Glycidic Ester Condensation... 

The Gattermann-Koch reaction when appHed to alkenes or alkanes gives ketones or acids but not aldehydes. However, the Vilsmeier aldehyde synthesis can be appHed to aUphatic compounds. For example, 1,2-diaLkoxyethylenes react with /V-methy1foTmani1ide and POCl to give alkoxymalondialdehydes ... 

Gabriel synthesis Gattermann aldehyde reaction Gattermann reaction Gattermann-Koch reaction Gomberg-Hey reaction Grignard reaction... 

The range of the reaction was extended by the elegant aldehyde synthesis of Gattermann and Koch. If a mixture of carbon monoxide and hydrogen chloride is allowed to act in the presence of aluminium chloride (and cuprous chloride) on toluene (benzene is less suitable), the reaction occurs which might he expected with formyl chloride if this substance were capable of existence. 

Gattermann aldehyde synthesis, 9, 2 Gattermann-Koch reaction, 5, 6 Germanes, addition to alkenes and alkynes, 13, 4 Glycals,... 

Crafts alkylation and acylation (Section 22-4E and 22-4F), the Gattermann-Koch reaction for preparation of aldehydes from arenes and carbon monoxide (Section 22-4F), and the Kolbe-Schmitt, Reimer-Tiemann, and Gattermann reactions for synthesis of acids and aldehydes from arenols (Section 26-1E). 

Nevertheless, compared to other formylation reactions, such as the Duff Formylation, Gattermann Aldehyde Synthesis, and Gattermann-Koch Formylation, the Reimer-Tiemann reaetion is the only one that occurs under basic conditions, and in certain cases, it is the only feasible method for the direct formylation, e.g., the formylation of oestrogens. ... 

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

The Gattermann-Koch synthesis of aromatic aldehydes involves a Friedel-Crafts formylation by CICHO in the presence of aluminum chloride and CuCl catalysts. s.n xhe reaction proceeds without Cu, but at much higher pressures. s... 

The Gattermann-Koch reaction can be carried out under two major types of conditions i.e. at atmospheric pressure where CU2CI2 is necessary as a promoter or complexing agent and secondly at high-pressure where the presence of CU2CI2 is not necessary. The Gattermann-Koch aldehyde synthesis is a suitable method for the preparation of simple aromatic aldehydes such as benzaldehyde and tolualdehyde. Formylation of ortho and... 

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