Oxidation of alkoxyphenols. Part XI. Further observations on the influence of an o-methoxy-group

Abstract

Ferricyanide oxidation of 3-t-butylguaiacol and of 4,6-di-t-butylguaiacol leads, respectively, to a polymer and a phenoxycyclohexadienone. Acid hydrolysis of the latter follows an unusual course. From 2-methoxy-1-naphthol a 1,1′-binaphtho-4,4′-quinone was obtained, and from 1-methoxy-2-naphthol a naphthyloxynaphthalenone. Ferric chloride oxidizes 3-methoxy-2-naphthol to a 1,1′-binaphthol. With lead tetra-acetate, 2-methoxy-1-naphthol gives 2-methoxy-1,4-naphthaquinone, 1-methoxy-2-naphthol gives 1-acetoxy-1-methoxy-1H-naphthalen-2-one, and with 3-methoxy-2-naphthol the chief products are the 1,1-diacetate and the 1,2-quinone. Frémy's salt oxidatively demethylates 4,6-di-t-butyl-guaiacol. No spiroketal trimers were obtained from these compounds, but co-oxidation of 2,2′-dihydroxy-3,3′-dimethoxy-5,5′-di-t-butylbiphenyl and 4-methoxy-2-t-butylphenol appears to give one.