Eine neue, breit anwendbare Synthese für aromatische Aldehyde

Autor: Alexander Gissel, Willi Kantlehner, Michael Ciesielski, Erwin Haug, Richard Haas, Georg Ziegler, Oliver Scherr, Markus Vettel
Rok vydání: 2000
Předmět:
Zdroj: Journal für praktische Chemie. 342:297-310
ISSN: 1521-3897
1436-9966
DOI: 10.1002/(sici)1521-3897(200003)342:3<297::aid-prac297>3.0.co;2-x
Popis: Diformamide (1) reacts with activated aromatic compounds like toluene, anisole, m-xylene, 1,2-dimethoxybenzene in the presence of AlCl3 to give N-(diarylmethyl)-formamides 2a—d, the corresponding aromatic aldehydes 3—6 are formed as by-products in low yields. From N,N-dimethylaniline and 1/AlCl3 the triphenylmethane derivative 7 can be obtained. The reaction of anisole with N-methyl-diformamide (9) affords the formamide 10. The mixture of formamide, P4O10 and AlCl3 reveals to be a reagent which is capable to formylate toluene and anisole, resp. Triformamide (14)/AlCl3 is an effective formylating system which allows the preparation of aromatic aldehydes (e.g.3,4,17—32) from the corresponding aromatic hydrocarbons. Aluminiumchloride can be replaced by borontrichloride. The yields of the formylation reactions depend strongly from the reaction conditions (molar ratio: aromatic hydrocarbon/AlCl3/14; solvent, reaction temperature). The scope of the reaction covers nearly complete those of the Gattermann-Koch-, Gattermann- and Vilsmeier—Haack-reaction.
Databáze: OpenAIRE