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Highlighting the role and importance of organic synthesis in every aspect of life.

You don’t need to look very far to appreciate the huge variety of colours that occur in nature. However, for much of our history, we didn’t have any ways of developing coloured compounds for use in places like the textile industry.
Today, though, developments in organic chemistry mean we can synthesise a huge diversity of dyes and pigments, and it was estimated that the dye industry contributed £3.8 billion to GDP in 2007, while supporting 69,000 jobs.

Serendipitous synthetic dye

The first ever synthetic dye was discovered by accident, by a British chemist called William Henry Perkin. Perkin was trying to synthesise quinine, the antimalarial drug. He treated aniline with an oxidising agent, potassium dichromate, K₂Cr₂O_7.

Perkin would have performed a combustion analysis, so he knew that aniline contained carbon, hydrogen and nitrogen, and that he needed to add oxygen in order to make quinine. However, he had no advanced analytical tools such as NMR, as we do today, so he would have known little about the products he was creating.

When Perkin performed the reaction, a black tarry product was formed, and from that Perkin isolated a small amount of a bright purple substance. Perkin was not just a chemist, but also an entrepreneur, and he realised the potential of this compound as a dye.

He named the purple product mauveine, and set up a factory to produce large quantities of the dye. The dyed materials were highly sought after – Queen Victoria famously wore a mauveine-dyed dress!

Dyes for the future

Today there is a still a need for new synthetic dyes, and a range of exciting new applications, such as lasers and dye-sensitised solar cells. At the same time, chemists are working to develop more efficient processes and reduce the environmental impact of dye making.

Synthesis of diketopyrrolopyrroles

For example, chemists have developed a simple, efficient scalable method for producing diketopyrrolopyrroles – an important group of red pigments. Originally, they were only produced as a by-product of another reaction, in small yields.

So organic chemists set to work, and developed a pathway to build these compounds from readily-available starting materials. Not only that, but the route also allows many different related compounds to be made, by changing the substituent on the ring to change the optical properties of the dye.

Also of Interest

A forgotten anniversary?

Has the significance of William Henry Perkin's synthesis of the purple dye mauveine begun to fade?

The Perkin family legacy

Today’s colour lovers, organic chemists and university students have a lot to thank the late 19th century Perkin family for, as Mike Sutton explains.

Colour Chemistry

Copyright: 2007
Robert Christie
This book provides an up-to-date insight into the chemistry behind the colour of the dyes and pigments that make our world so colourful.

Profile: A bright career

Stephen Batchelor really can help you achieve a ‘whiter wash’. With over 70 patents, he is one of Unilever’s top inventors. Manisha Lalloo discovers what inspires him.