IN connection with our studies of the synthesis of 5-phenyl-l,4-benzodiazepinones,1 we have prepared a series of 2-amin0-2'-fluorobenzophenones.~ These compounds undergo internal nucleophilic exchange to give high yields of the corresponding 9-acridones. In contrast to substituted 2-amino-2'-chlorobenzophenones, which, as we have verified, do not cyclize under these condition^,^ the fluorine is sufficiently activated by the orthocarbonyl group to react readily with the aromatic amine.Both solvent apd catalyst affected the yield and it was determined that NN-dimethylformamide was the preferred solvent. The use of potassium carbonate as a catalyst significantly improved the yields of the 9-acridones in all cases. The catalytic effect of other salts was not investigated. N-Substituted 2-amino-2'-fluorobenzophenones were also easily cyclized by this method, although in NN-dimethylformamide only 2-chloro-9acridone was obtained from the 5-chloro-2'-fluoro-2-toluene-~-sulphonamidobenzophenone. We were, however, able to obtain the desired 2-chloro-lO-toluene-$-sulphonyl-9-acridone directly by using 2-ethoxyethanol as solvent.ExperirnentaZ.-M. p.s were determined microscopically on a hot stage and are corrected. The acridone structure of known compounds not directly compared with authentic samples was confirmed by a comparison of experimental and published ultraviolet ~p e c t r a , ~ and by satisfactory analysis.CjGclization of 2-amino-2'-fluorobenzophenones to 9-acridones. A typical procedure is described. A solution of 2-amino-2'-fluoro-5-nitrobenzophenone (1.0 g., 3.85 mmoles) and potassium carbonate (0-65 g., 4.75 mmoles) in NN-dimethylformamide (20 ml.) was refluxed for 17 hr., cooled, diluted to 100 ml. with water, and filtered. The precipitate was washed successively with water and boiling methanol, and was dried to give 2-nitro-9-acridone (0.8 g., 87%), m. p. >350".

The Action of Oxidising Agents on Osaxones and Osotri-Part II.* axoles.By H. EL KHADEM a n d 2 ~~1 M. EL-SHAFEI. Conversion of glucose arylosazones into osotriazoles by copper or ironStronger oxidising agents salts, or by bromine water, is due to oxidation. yield 2-aryl-1 : 2 : 3-triazole-4-carboxylic acids.CARBOHYDRATE phenylosazones are converted into phenylosotriazoles and aniline when refluxed in aqueous copper su1phate.l Teuber and Jellinek recently effected a similar change by nitrosodisulphonate. In the present work various inorganic salts were refluxed with aqueous suspensions of glucose phenylosazone (I) : cupric chloride, nitrate, and acetate, ferric chloride, ferric sulphate, and potassium ferricyanide readily yielded glucose phenylosotriazole (11). The corresponding salts in lower states of valency and salts with no oxidising character were ineffective.Other oxidising agents were also used; bromine water with glucose phenylosazone (I) in the cold yielded glucose p-bromophenylosotriazole, directly obtained also from glucose phenylosotrjazole and bromine water. The fact that 9-bromophenylosotriazoles are less soluble than the corresponding phenyl derivatives, together with the simplicity and good yields obtained, render this reaction of value for the identification of osazones and osotriazoles.

A new type of tliermochromic ethylene [I) is photo-oxidised in presence of oxygen, giving anthraquinone and fluorenone ; it is not affected by sunlight in a carbon dioxide atmosphere. I n the early stages of the reaction a peculiar reversible colour change was achieved. On the other hand, a related compound (V) and a derivative (VI) are photodehydrogenated in presence of oxygen or carbon dioxide with the formation of highly condensed ringsystems.THERMOCHROMISM and piezochromism exhibited by certain polynuclear ethylenes, e.g., dianthraquinone and dixanthylidene, have been attributed to diradical formation or internal betaine structure.2We here report a new thermochromic ethylene, 9-9'-fluorenylideneanthrone (I), a yellowish-brown solid (violet melt) which gives deep violet solutions that exhibit thermochromism. When pressed, the crystals change to deep violet (piezochromism). The fact that it suffers photo-oxidation with cleavage to anthraquinoiie and fluorenone (the first case of this type in thermochromic ethylenes) seems to favour the existence of a diradical whose formation is enhanced by irradiation. Acceleration of oxygen absorption with time

Copper precipitated during conversion of osazones into osotriazoles with copper sulphate causes ortho-debromination similar to that of o-bromocarboxylic acids. The action of copper sulphate, bromine water, and potassium permanganate on p-methoxyphenyl-and carboxyphenyl-osazones is investigated.

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