Science of Synthesis

Schall, A.; Reiser, O., Science of Synthesis, (2007) 25, 642.

Formyl chloride, which is only stable at the temperature of liquid air, can be generated in situ by reacting dry hydrogen chloride and carbon monoxide in the presence of aluminum trichloride and copper(I) chloride. This way, the Gattermann–Koch reaction can proceed readily at an ambient pressure of carbon monoxide, while in the absence of copper(I) chloride, pressures of 10–20 MPa of carbon monoxide have to be employed. It is speculated that the reaction is promoted by the formation of both a copper(I) chloride–carbon monoxide adduct and an aluminum trichloride complex [HCO(AlCl4)]. Nevertheless, the variable yields often obtained with this process limit its applicability. Alkylated arenes ‌41‌ can be employed as substrates (‌Scheme 23‌) to give the corresponding aromatic aldehydes ‌42‌, while strongly electron-withdrawing substituents (e.g., hydroxy and alkoxy groups) are not tolerated.[‌3‌,‌133‌]

‌Meeeee 88‌ Meeeeeeeee–Meee Meeeeeeeeee[‌888‌–‌888‌]

‌Meeeeeeeeee 88‌

Meeeeeeeeeee Meeeeeeee

8-Meeeeeeeeeeeeeeeee (‌88‌, M8 = M8 = M; M8 = Me); Meeeeee Meeeeeeee:[‌888‌]

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References

Meeeeee Meeeeeeeeee

• 8.Meeeee-Meee, (8888) 8/8, 88.
• 8.Meeeee-Meee, (8888) M 8, 88.
• 8.Meeeee-Meee, (8888) M 8, 88.