EMIL FISCHER WAS ONE OF THE WORLD’S GREATEST CHEMISTS
Nobel Prize winner attended university only after father said he was ‘stupid’
A small vial with a few milligrams of potassium cyanide (KCN) sits in my top drawer. But it is no ordinary cyanide. It contains a carbon atom, the socalled C-13 isotope, that has one more neutron in its nucleus than C-12, the most common form of carbon. Given that C-13 has a natural abundance of only 1 per cent, a sample that is enriched in this isotope is difficult to make and cost a small fortune back in 1970 when I was beginning my research as a graduate student. But now for me its real value lies in triggering memories.
My research involved nuclear magnetic resonance spectroscopy (NMR), a sophisticated instrumental technique that gives insight into molecular structure. NMR can detect C-13 but not C-12, so my project involved synthesizing molecules that had a C-13 atom in a specific position. Our particular interest was directed toward carbohydrates, and my first task was to make glucose that had a C-13 atom in a specific position. This was my introduction to synthetic organic chemistry, a field that has captivated me ever since.
The method used to make the “labelled” glucose was the “Kiliani-Fischer” synthesis, based upon adding an atom of carbon to arabinose, a molecule that had one less carbon than glucose. The source of the added carbon was cyanide. Not only did this reaction introduce me to the wonders of organic synthesis, it introduced me to Emil Fischer, the man who if judged by the breadth of his work, was certainly one of the greatest chemists who ever lived.
Fischer almost didn’t get a chance to develop his scientific talents because his father insisted that Emil take over the family business, which he himself had developed without the help of any higher education. But Emil did not show a great aptitude for commerce and after struggling for six months his father finally told him: “You had better go to university. You are too stupid to be a businessman. Besides, we can use a chemist in the cotton mill we have just acquired.” So in 1872, Emil Fischer went off to study chemistry. But he would never become a simple chemist at his father’s cotton mill. He would end up doing something far more important with cotton. He would unravel its molecular mysteries. Emil Fischer was destined to become the father of carbohydrate chemistry by laying the foundations to the understanding of the molecular structure of these fascinating substances.
The brilliant German chemist was the first person to carry out a total synthesis of glucose, the fundamental building block of cellulose and starch. This was a monumental achievement at the time. Fischer’s success in determining the molecular structure of carbohydrates was partly due to his accidental discovery of a reagent known as phenylhydrazine that formed well-defined crystalline derivatives with carbohydrates. This solved a basic problem, namely that carbohydrates usually formed syrups that were very difficult to work with. Unfortunately, phenylhydrazine is a toxic substance, a fact that Fischer did not realize. He went on to do a great deal of work in the area of amino acids and proteins and studied uric acid extensively. This finally gave him some public exposure. Fischer, with colleague Josef von Mering, converted uric acid into diethylbarbituric acid, which had amazing sleep-inducing properties. They called it Veronal, after Verona in Italy, a town von Mering suggested was a little sleepy.
Veronal became a widely sold sleep remedy and brought fame to Fischer. One day at a resort he was approached by novelist Hermann Sudermann, whom Fischer was not particularly fond of. The writer thanked the chemist for the invention of Veronal, saying somewhat cynically that he had trouble sleeping but the drug solved his problem. At first, he needed two pills, then only one, and finally it was enough for him to read the label to fall asleep. Fischer retorted that he also had to thank Sudermann because he was also instrumental in providing sleep. Emil said that at first, he had to read three pages of a novel to fall asleep, then two and now it was enough to read the title.
Emil Fischer received the Nobel Prize in 1902. His father, unfortunately, did not live to see his “stupid” son honoured in this fashion. Fischer was a lot less lucky in his private life than in his professional one. His wife died young and he lost two sons in the First World War. He developed chronic phenylhydrazine poisoning, which he erroneously interpreted as incurable cancer and he committed suicide with cyanide. Cyanide was, of course, the critical reagent Fischer used in his original glucose synthesis. It brought him fame and death. And my duplication of his work with that special C-13 labelled cyanide was a springboard into my career in teaching organic chemistry.
His father, unfortunately, did not live to see his ‘stupid’ son honoured in this fashion.