4-tert-Butylphenols can be easily transformed into 4-fluorophenols, provided that no coordinating moiety is present in 2-position, in a two step procedure under mild and safe conditions. The first step leads to 4-tert-butyl-4-fluorocyclohexa-2,5-dien-1-ones through an oxidative fluorination with [bis(trifluoroacetoxy)iodo]benzene and triethylamine tris(hydrofluoride), and is followed by an acid catalyzed aromatization with loss of isobutene. When extended to 4-tert-butylacetanilide, this method delivers 4-fluoroacetanilide in a single step but in a modest yield.
tert-Butylphenols (I) having no coordinating moiety in the 2-position are oxidatively fluorinated with [bis(trifluoroacetoxy)iodo]benzene in the presence of Et 3 N·3HF as the best fluoride source. An acid-catalyzed aromatization transforms the fluorocyclohexadienones (II) into the final fluorophenols (III) with loss of isobutene. Extension of this method to p-tert-butylacetanilide (IV) provides the p-fluoroacetanilide (V) in a single step but in modest yields. -(BIENVENU, A.; BARTHELEMY, A.; BOICHUT, S.; MARQUET, B.; BILLARD, T.; LANGLOIS*, B. R.; Collect.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.