' Mustard Gas COOCH3 \y t Methyl salicylate Oil of Wintergrreen Ethylene Hg(ONC)3 ** t Mercury As t / Fulminate .r^OH i Detonator Ethyl alcohol fNcHO Salicylic acid Drug ^ NaSojs^ Fig OC,H, OC,H 0" H H Yellow Dye u Benzaldehyde Almond Flavor k^NaSO, t ACH3 NaHSOg Para-nitro toluene sodium sulfonate NH,r >CH3 NHj Toluylene diamine N N AnH2 NH2 HCl Red Dye 0OCH3CO COOH Acetyl salicylic acid Aspirin 0; OH )0H f^NHj Black Dye Formula Unknown NO Dinitro chlorobenzene OH . Arsphenamine / Ow OCjHX "Salvarsan" / NH2COCH5 \ t NO2 Phenacetin Drug NO^'^/NO Phenol ( Carbolic acid) "n-h Antiseptic // o O Saccharin + \ACH3^ Toluene 1 _ ACHg Para-nitro toluene I NO^k^NOa NO^l Dinitro toluene Benzene ;enz< I Indigo and many other Dyes t Picric acid High Explosive t /Nno2_^ ^nh_2_^ I^n Nitro benzene I Dinitro benzene i NO \ ^CH NO, NO .IJno2 nhIsJ Trinitro toluene T.N.T. High Explosive Paranitraniline 1 Red Dye Aniline IN N-H Diphenyl - amine Stabilizer for Smokeless Powder Dimethyl aniline (CH,), (CH3)2 NO2 NOz Hexanitro diphenylamine High Explosive Chlorobenzene NO2 _^ AnCHjNO^ Tetryl High Explosive /NnccHj), Violet Dye (CHs)^ 302. A few of the interrelationships among aromatic chemical compounds. 690
"BETTER THINGS" FROM COAL 691 perfumes. Today coal tar is the chief source of our perfumes. It is possible to duplicate any natural perfume, once its composition is known, but inasmuch as thirty or forty ingredients must often be skillfully blended to produce a given perfume, one can understand why cheap perfumes, which contain only a few ingredients, do not have the quality of odors equal to perfumes of more complex nature. In 1939 the E. I. du Pont de Nemours Company produced a synthetic musk, which has the extraordinary properties of natural musks in fixing a perfume. (Fixing means causing a perfume to remain on a material for a relatively long time.) Dyes. The development of synthetic dyestuffs had its origin in William Henry Perkin's accidental discovery of mauve in 1856 during his research on quinine. Today the chemist synthesizes from coal-tar products dyes which are very much cheaper than the inferior natural colors which they replace. The famous Tyrian purple obtained from shellfish was so expensive that only kings could afford it, and purple came to be considered the badge of royalty. This dye was obtained from tiny sacs behind the heads of a kind of shellfish of the eastern coast of the Mediterranean Sea. In 1909 Friedlander analyzed this dye and found that it had already been synthesized and discarded because of its inferiority to other dyes never found in nature. Any dye found in nature can be duplicated and prepared in a purer condition in the laboratory once its composition has been determined. The knowledge of its composition is like an architect's blueprint, for anyone who understands the methods of building molecules can follow the plan once it becomes available. The analysis of dyes is not a simple process. Thus the Badische Anilin und Soda-Fabrik spent $5,000,000 and seventeen years in chemical research learning to make indigo. Then they reduced the price from $4 a pound to 15 cents a pound and received over $12,000,000 a year from their sale of this one dye. Not only is synthetic indigo cheaper, but it is purer and more uniform than vegetable indigo. Previous to the synthesis of indigo, it had been obtained from India, where nearly a million acres produced an annual crop valued at about $20,000,000. Within less than twenty" years this profitable industry was wiped out.^ Though it was a loss to India, it was a gain to the world. Today man has available thousands of dyes which can duplicate any shade found in nature and are more suitable for use. Most of • J. G. Crowther says that a million native workers in India and Burma died of starvation as a result!