Naphthoyl benzoic acid

Naphthanthraquinone may be prepared by the condensation of phthalic anhydride and naphthalene in the presence of aluminum chloride to alpha naphthoyl benzoic acid and the subsequent dehydration of the alpha naph-thoyl benzoic acid with sulfuric acid.63 To obtain high yields of product in the proper condition of purity necessitates somewhat different procedure... 

Naphthalene and phthalic anhydride in benzene, o-dichlorobenzene, or tetrachloroethane reacted with A1C1S -> mixture of 60-70% a- and 30-40% / -naphthoyl-o-benzoic acid (Y 91-93%) with HB02 and H2S04 warmed at 60° for 6 hrs. 1,2-benzanthraquinone (Y 84%). —In nitrobenzene and CS2, the Friedel-Crafta reaction with A1C13 also gives a mixture of isomers, but in lower yields.—The ring closure with A1C13 is not uniform. (A. Eitel and R. Fialla, M. 79, 112 (1948) cf. Synth. Meth. 2, 746 5, 604.)... 

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