SYNTHESIS OF AROMATIC ALDEHYDES VIA 2-ARYL-N,N'-DIACYL-4-IMIDAZOLINES

Article abstract of DOI:10.1016/0040-4020(80)80230-4

Diacylimidazolium ions yield adducts with aromatic compounds.Thus the N,N'-diacetylimidazolium ion and indole gives 1,3-diacetyl-2-(3-indolyl)-4-imidazoline.Less reactive substrates such as thiophene, anisole and 1,3-dimethylbenzene fail to react with this reagent but do form adducts (e.g. 1,3-bis-(trifluoroacetyl)-2-(2-thienyl)-4-imidazoline) with an imidazole/trifluoroacetic anhydride reagent.All of the adducts could be converted to the corresponding aldehyde under mild conditions.The synthetic scope of the new synthesis is similar to that of the Vilsmeier-Haack reaction.