Leopold
Stephen Ruzicka* was born on September 3, 1887, in Vukovar, a small Croatian
town on the Danube, somewhat east of its confluence with the Drava. His father,
Stjepan Ruzicka, was a cooper; his mother's maiden name was Ljubica Sever. His
great-grandparents included a Czech, from whom the name Ruzicka stems, an Upper
Austrian and his wife from Wurtemberg, the other five being Croats. His ancestors
were artisans or farmers, who had enjoyed at most a few years of schooling.
After the early death of his father in 1891, he returned with his mother to
her birthplace, Osijek, on the Drava somewhat west of its junction with the
Danube. There he attended the primary school and the classical gymnasium where
the Croatian language was used. He was a fairly good pupil in a general way,
but really interested only in physics and mathematics. The other subjects, including
the purely descriptive sciences, left him cold. There was no chemistry in the
curriculum but, nevertheless, he decided to study this subject out of his interest
in the composition of natural products.
He wanted to study at the Zurich Polytechnic Institute but found to his dismay
that an entrance examination was required not only in chemistry but also in
"descriptive geometry". He decided to go instead to Germany, where anyone with
a completed secondary school education was acceptable as a student at a University
or Technical Institute without having to undergo additional entrance examinations.
He chose the Technische Hochschule at Karlsrohe, where he began his chemical
studies in 1906. This step proved to be decisive for his future. Only later
did he discover that in Zurich the curriculum, including practical work, was
organized on a very rigid basis; still in 1906 attendance at the lectures was
or could be checked. In Karlsruhe, on the other hand, there was considerable
freedom. He completed his laboratory courses in 1 3 /4 years and then immediately
started his doctoral work on ketenes with Professor Staudinger, who was, at
27, only 6 1/2 years older. There were few bureaucratic formalities; he had
attended the prescribed lectures neither in chemical technology nor, unfortunately,
in physical chemistry and physics.
After two years of research work Ruzicka was a "Dipl. Ing", and two weeks later
"Dr. Ing". Staudinger appointed him as his assistant, and they together entered
the quite unexplored field of the active constituents - named by them pyrethrins
- of Dalmatian insect powder, a plant product, toxic to insects and other coldblooded
animals. They thus opened a new chapter of alicyclic chemistry, which was then
as unfamiliar to Ruzicka as it was to Staudinger.
In October 1912 he followed Staudinger who became Willstätter's successor
at the newly dubbed "Eidgenössische Technische Hochschule" (ETH, Swiss
Federal Institute of Technology) at Zurich. In Switzerland he found not only
a second homeland but also a peaceful and convivial environment that brought
with it all the conditions for uninterrupted research. In 1917 he acquired Swiss
citizenship.
In the previous year he had already started independent work and this decision
initiated the most fruitful and happy decade of his life, when he could work
at the laboratory bench from morning to night, on problems of his own choosing,
with no teaching responsibilities, except one hour weekly from 1918 onward.
During the years 1920-1924 he laid the fundaments of all his future work.
For the accomplishment of his Habilitation work (necessary to become a "Privatdozent")
in 1916-1917 he was glad of the support of the oldest perfume manufacturers
in the world, Haarman & Reimer, of Holzminden in Germany. The starting-point
for their collaboration was the Tiemann formula for drone; the results were
the total synthesis of fenchone and the extension and interpretation of the
Wagner rearrangement (this term was then introduced by him). After his habilitation
in 1918 the firm of Ciba, Basle, became interested in his work on the preparation
of quinine-like compounds. With various co-workers, the first synthesis of b-collidine
and of linalool, the partial synthesis of pinene, and a series of investigations
in the monoterpene field were carried out.
In 1921, the Geneva perfume manufacturers Chuit, Naef & Firmenich, asked
him to collaborate with them. By this time the investigations that were to lead
to the elucidation of the constitutional formulas of the higher terpenes has
already been started. In the perfumery and sesquiterpene domain the total syntheses
of nerolidol and farnesol were carried through. The structure of jasmone was
established, Tiemann's irone formula corrected, and synthetic work in these
fields undertaken. But by far the most important fruits collected in the perfumery
garden were the elucidations of the structures of the naturally occurring musk
perfumes, civetone and muscone. Following these discoveries Ruzicka and his
co-workers were able to prepare the whole series of alicyclic ketones with 9
to over 30 carbon atoms as ring members, compounds that had previously been
believed to be incapable to existence.
Most of the years 1925-1926 he spent with his friends in Geneva. From October
1926 till 1929 he was Professor of Organic Chemistry at the University of Utrecht.
Although he was very happy in Holland, he decided to accept the invitation of
the ETH to return to Zurich. The main reason for this decision was the strength
of the Swiss organic chemical industry, especially its pharmaceutical and perfumery
branches, which required the skill and energy of a whole army of chemists with
a thorough training in modern organic chemistry. This circumstance was not only
a challenge to the teaching and research abilities of the professors; it also
encouraged students to acquire the necessary understanding of the theories and
methods to equip them for a career in these industries. The three-fold community
of professors, students and industry was thus bound together by bonds of common
interest.
In 1930, the Ciba renewed the contact with his laboratory. This association
led in a few years to scientifically as well as industrially important successes
in the field of the male sex hormones. From 1937 the Rockefeller Foundation
generously provided financial backing for the research on natural compounds,
especially the triterpenes and steroids, free from any special conditions. With
the two industries, there was thus formed a strong group of constant supporters
of his research team which had grown much in the meantime.
Professor Ruzicka holds eight honorary doctorates (4 Science, 2 Medicine, 1
Natural Sciences, 1 Law) 7 prizes and medals, 24 honorary memberships of chemical,
biochemical and other scientific societies, 18 honorary, ordinary and foreign
memberships of scientific academies. The circle of his friends is very wide,
not only geographically but also spiritually, including the Vatican City as
well as Moscow. He feels that the honours which he has won should be distributed
among the whole team of his co-workers, and that, to mention only one example,
the laudation of his 1936 honorary Doctor diploma of Harvard (tercentenary celebration
of the oldest USA university) should more realistically be read in the plural
form "... to the team of chemists, daring in their attacks, brilliant in their
methods, successful in their interpretations of the architecture of nature's
baffling compounds", since every member of the team helped to transform the
youthful dreams of its oldest member into reality.
Ruzicka married Anna Hausmann in 1912, and Gertrud Acklin in 1951. He has no
children, and lives in Zurich. His hobbies are old Dutch and Flemish paintings
and alpine plants gardening.
* The pronunciation can be best explained by the French transcription "Rougitchka".
From Nobel Lectures, Chemistry 1922-1941, Elsevier Publishing Company, Amsterdam, 1966
This autobiography/biography was written at the time of the award and later published in the book series Les Prix Nobel/Nobel Lectures. The information is sometimes updated with an addendum submitted by the Laureate. To cite this document, always state the source as shown above.
Leopold Ruzicka died on September 26, 1976.