Étard reaction

The Étard reaction is a chemical reaction that involves the direct oxidation of an aromatic or heterocyclic bound methyl group to an aldehyde using chromyl chloride. [cite journal
author = Étard, A.
title = Sur la synthèse des aldéhydes aromatiques; essence de cumin
journal = Compt. Rend.
volume = 90
pages = 534
year = 1880
url = http://gallica.bnf.fr/ark:/12148/bpt6k3047v/f532.table
format = Dead link|date=May 2008 – ^{[http://scholar.google.co.uk/scholar?hl=en&lr=&q=author%3A+intitle%3ASur+la+synth%C3%A8se+des+ald%C3%A9hydes+aromatiques%3B+essence+de+cumin&as_publication=Compt.+Rend.&as_ylo=1880&as_yhi=1880&btnG=Search Scholar search]} ] [cite journal
author = Étard, A.
title = Recherches sur le rôle oxydant de l'acide chlorochromique
journal = Ann. Chim. Phys.
volume = 22
pages = 218–286
year = 1881
url = http://gallica.bnf.fr/ark:/12148/bpt6k348629/f217.table
format = Dead link|date=May 2008 – ^{[http://scholar.google.co.uk/scholar?hl=en&lr=&q=author%3A+intitle%3ARecherches+sur+le+r%C3%B4le+oxydant+de+l%27acide+chlorochromique&as_publication=Ann.+Chim.+Phys.&as_ylo=1881&as_yhi=1881&btnG=Search Scholar search]} ] [cite journal
author = Hartford, W. H.; Darrin, M.
title = The Chemistry Of Chromyl Compounds
journal = Chem. Rev.
volume = 58
pages = 1–61
year = 1958
doi = 10.1021/cr50019a001] It is named for the French chemist Alexandre Léon Étard (5 January 1852, Alençon – 1 May 1910). For example, toluene can be oxidised to benzaldehyde:

Other oxidation reagents like potassium permanganate or potassium dichromate oxidize to the more stable carboxylic acids.

References