Reactions ofQuinones with Aromatic Ethers. Part 1. Polyalkoxydibenzo[ fg,op]naphthacene-188-quinones from Chloranil and 383'8484'-Tetra-al koxybiphenyls By 0. C. Musgrave" and C. J. Webster, Chemistry Department, The University, Old Aberdeen AB9 2UE Chloranil oxidises 3,3',4,4'-tetramethoxybiphenyl efficiently in 70% (v/v) aqueous sulphuric acid to 2,5,6,9,12,13hexamethoxydibenzo[fg,op]naphthacene-l,8-quinone (2 ; R1 = R2 = R3 = Me) from which are prepared the corresponding leucoacetate, the leucomethyl ether, and 1,2,5,6,8,9,12,13-octa-acetoxydibenzo [fg,op] naphthacene (3; R1 = R2 = R3 = Ac, X = OAc). Volatilisation of the quinone in the mass spectrometer is accompanied by abstraction of hydrogen and methyl groups. The oxidation of 3,3'bistrideuteriomethoxy-4,4'-dimethoxybiphenyl (I : R 1 = Me, R2 = CD,) g.ives a mixture of the expected [2H12]quinone and a [2H,]quinone( 2; R 1 = R3 = Me, R2 = CD,) formed by intramolecular trans-etherification. 3,3'.4,4'-Tetraethoxybiphenyl is oxidised to 2,5,6,9,12,13-hexaethoxydibenzo[fg.op]naphthacenequinone ( 2 ; R1 = R2 = R3 = Et).ALKYL ARYL ETHERS react with many types of oxidising agent1 but comparatively little is known of their behaviour towards quinones. With the object of preparing polycyclic aromatic compounds we have investigated the reactions of o-dialkoxybenzenes and related substances with chloranil in aqueous sulphuric acid.