84-12-8

ChEBI: An orthoquinone that is the 5,6-diketo derivative of 4,7-phenanthroline.

Phanquinone ,Yick-Vic Chemicals and

2 parts of 6-methoxy-4:7-phenanthroline are mixed with 10 parts by volume of concentrated sulfuric acid and while cooling with a mixture of ice and sodium chloride, with 6 parts by volume of fuming nitric acid (density = 1.51), and the whole is heated for 2 h at 120°C. The reaction solution is poured on to ice, its pH value is adjusted to 7 by means of a 10 N solution of caustic soda, after standing for 2 h the whole is filtered with suction to remove the precipitate which separates, and the latter is washed with hot water. After recrystallising the product from methyl alcohol and drying it at 100°C under 0.1 mm pressure, there are obtained 1.8 parts (i.e. 90 % of the calculated yield) of 4:7-phenanthroline-5:6-quinone in the form of pale yellow crystals melting at 295°C.

Antiamebic

Poison by ingestion. Mutation data reported. When heated to decomposition it emits toxic fumes of NOx.

The dione crystallises from MeOH. The mono-oxime forms yellow crystals from MeOH with m 250o(dec), the di-oxime forms yellow crystals from MeOH with m 300o(dec) and the mono-semihydrazone forms yellow crystals from MeOH with m 195o(dec). [Druey & Schmidt Helv Chim Acta 33 1080 1950, Beilstein 24 III/IV 1741.]