 by Preston MacDougall January 11, 2005
"Haute couture" is, by definition, the currency of French fashion houses, and in 1857 they began to take notice of the Empress Eugénie's fondness for the color mauve. She said it matched the color of her eyes. At the time, there were just three ways to make purple dyes. The first, dating back to the Roman Empire, was a time-consuming process beginning with the giblets of a particular shellfish found in the eastern Mediterranean sea. In ancient times, the rarity of this dye earned it the nickname Royal purple, but it was also referred to as Tyrian purple, after the city of its origin, Tyre, in modern day Lebanon. The second method was also ancient, but it was plant-based, hence less expensive. Originating with the Vikings, Lichen purple was brilliant, and its shade could be varied, but best of all there was no reliance on Middle East suppliers. This was the method used to dye the Empress's dress, but only because the third, and by far the cheapest, method had just been discovered by a teenage English chemist working in his garage. A young man's colorful life story is told in the recent book "Mauve - how one man invented a color that changed the world" by Simon Garfield. William Perkin had been a student at the fledgling Royal College of Chemistry in London. While still a teenager, he ventured out on his own. His goal was to use the beginnings of what later became known as "organic chemistry", to mass-produce quinine for the treatment of malaria. Like dyes, until then most medicines were painstakingly extracted from plants or animals. Quinine, the most sought-after drug in the world at the time, was obtained from the bark of cinchona trees found in Bolivia and Peru. Perkin sought to become rich manufacturing it from so-called "coal-tar", the unwanted tailings of the coal gasification process that lit the lamps of European streets in those days. Instead, he obtained a dark sludge. Nowadays, when organic chemistry students at MTSU, or anywhere else, are left with a dark sludge in their flasks, as they often are, it usually means that they heated their reaction mixture too intensely, the pH was too low, too high, or some other misstep in the prescribed procedure. In any case, it's time to start over. Perkin, in his garage, wasn't following any known procedure. By trial, and luckily in error, he obtained not quinine, which wouldn't yield to the art of synthetic chemistry until 1944, but a new compound that was easily separated from the sludge by dissolving it in alcohol. The resulting solution was a shade of purple, close to that of lilac blossoms. Tannin mordants, long-used in the production of ink and the tanning of leather, were soon found to modify Perkin's compound so that cotton, as well as the more receptive silk, could be dyed a brilliant purple color, that resisted the mellowing effects of water and sunshine. He called his dye "analine purple" after the "magic" ingredient that he had stumbled across in the garage. However, to capitalize on the fashion trend being set by Empress Eugénie and her eyes, he soon called his synthetic dye "mauve". None of the other purple dyes could compete on either cost or quality, so, by the age of thirty-six, Perkin was one of the wealthiest self-made men in England. Inspired by Perkin's success, chemists throughout Europe began experimenting with coal-tar, and while they were at it, pushing the envelope of organic chemistry. To the "knights of the round-bottomed flask" the "Holy Grail" of synthetic dyes was indigo, and that was before James Dean rebelled without a cause. By the late 1800's an astounding 2,800 indigo factories existed just in India, where the botanical source grew abundantly. The race was won, in 1880, not by Perkin, but by a German chemist named Adolf von Baeyer. You can probably now guess which industry was next to undergo a revolution thanks to the ambitions of a teenage chemist in London. Aspirin was synthesized from salicylic acid, a common intermediate in the new dye industry, by a chemist working at Bayer. (Different spelling, and unrelated to Adolf, so your guess was a lucky one, like Perkin's.) The modern chemical and pharmaceutical industries are descendents of Perkin's garage. Another industry, ultimately derived from Perkin's garage, was born in Yonkers, New York, circa 1907. Without going into details, "I just want to say one word to you. Just one word: plastics."
Preston MacDougall is a chemistry professor at Middle Tennessee State University. His "Chemical Eye" commentaries are featured in the Arts and Public Affairs portion of the Nashville/Murfreesboro NPR station WMOT (www.wmot.org).
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