CONSTITUTION OF ANTHRACENE OR PARANAPHTHALINE. 685 
Action of Nitric Acid on Anthracene. 
Anthracene is but little acted on by cold nitric acid, but the boiling acid, even 
when moderately dilute, attacks it with considerable rapidity, and the products 
depend upon the strength of the acid and the length of time during which the 
action is continued. 
Oxanthracene.—When anthracene is boiled for some days with nitric acid of 
SG. 1:2, red fumes are evolved, and a resinous mass is obtained, which becomes 
hard and gritty in cooling. The same change may be more rapidly effected with 
acid of SG. 1:4, but the product is then liable to be contaminated with some other 
compounds. The substance was washed with water, and purified by crystal- 
lisation from alcohol or benzole. It is then obtained in crystals, which, when 
deposited from alcohol, are long silky needles, but from benzole are shorter and 
more compact. They have a light buff colour, have neither taste nor smell, 
and are insoluble in water, sparingly soluble in alcohol, and more so in benzole. 
They are completely soluble in boiling nitric acid of SG. 1-4, and are deposited 
unchanged on cooling. Concentrated sulphuric acid in the cold dissolves them 
with an orange colour, which becomes deep red on heating, and on dilution with 
water the oxanthracene is deposited unchanged. It sublimes when heated, and 
is deposited unaltered in fine needles of considerable length. It may be distilled 
without decomposition over quick-lime. Its volatility may be taken advantage 
of as a means of preparing it, as it is only necessary to boil anthracene in a 
retort with nitric acid, and to continue the heat until the acid has distilled over 
and the oxanthracene sublimes, any other compounds formed at the same time 
being decomposed. It contains no nitrogen, and analysis gave the following 
results :— 
4600 grains of oxanthracene gave 
I.< 13°525 grains of carbonic acid and 
1:670 grains of water. 
14-770 grains of carbonic acid and 
1-760 grains of water. 
4-600 grains of oxanthracene gave 
II. 
4:987 grains of oxanthracene gave 
JO 
13-600 grains of carbonic acid and 
1-650 grains of water, 





Experiment. Calculation. 
AGT hla tll Lonnie a 
ip Il. iil. 
Capbonjson Te Pee lon ween Yo-80638 osor77r ies: 68 
Hydrogen, .- : 3°99 3°92 3:99 3°85 iis 8 
Oxygen, : : 15°82 15°31 15°38 15°38 O, 32 
100:°00 100:00 100-00 100-00 208 
Its formula, therefore, is C,, H, O,, and it is derived from anthracene by the 
VOL. XXII. PART IIL. 8a 
