Otto Wallach was a German chemist born in the middle of the nineteenth century in the Kingdom of Prussia. For his work on alicyclic compounds, he was awarded the 1910 Nobel Prize in chemistry. Educated at a gymnasium that placed a greater emphasis on humanities than science, he began experimenting at home with various chemical reactions. He eventually earned a bachelor’s degree in chemistry from the University of Göttingen and a PhD there at the age of twenty-two. He joined the University of Bonn as a Lecturer of Pharmacy at the age of twenty-three, but was soon drafted into the Franco-Prussian War of 1870. He attempted to settle in Berlin following the war, but circumstances forced him to return to the University of Bonn for the second time. At this point, his mentor, Friedrich August Kekulé, discovered an old and forgotten cupboard brimming with essential oils and asked him to conduct research on them. As a result, he embarked on a lengthy and meticulous experimentation. Among other accomplishments, it resulted in the discovery of terpene and laid the groundwork for the modern perfume industry.
Childhood & Adolescence
Otto Wallach was born in Königsberg, a historic city in the Kingdom of Prussia, on 27 March 1847. Now a part of Russia, the town has been renamed Kaliningrad.
Gerhard Wallach, his father, was a high-ranking civil servant with a transferable job. He was born a Jew but converted to Lutheranism later in life. Otillie Wallach, his mother, was a Protestant German.
The family relocated shortly after Otto’s birth, first to Stettin and then to Potsdam. Otto began his education at a humanistic Gymnasium in Potsdam. In those schools, science subjects were rarely taught.
At that point, he developed an interest in literature and art history, which he maintained throughout his life. Simultaneously, he studied chemistry privately and conducted numerous experiments at home.
He eventually enrolled at the University of Göttingen in 1867, majoring in chemistry. Friedrich Wöhler, who is best known for his urea synthesis, was the department’s head at the time. He influenced young Wallach just as much as Professor Fittig and Professor Hübner.
Nonetheless, he left Göttingen University shortly thereafter to join the University of Berlin. He returned to Göttingen, however, after spending a semester in Berlin studying with August Wilhelm von Hofmann and G. Magnus and immersing himself in work.
Although the laboratory’s gas supply was turned off after 5 p.m. each evening, he continued his work by candlelight. He eventually earned a PhD in 1869 after only five semesters of work. His dissertation examined the toluene series’ position isomers.
Career of Otto
Wallach joined H. Wichelhaus in Berlin in 1869 after receiving his doctorate degree. While collaborating with him on b-naphthol nitration, he received an invitation to join Friedrich August Kekulé at the University of Bonn.
Accordingly, Wallach began his career at the University of Bonn in 1870 as a pharmacy lecturer. He was drafted into the army the following year and fought in the Franco-Prussian War, which began on 19 July 1870.
After the war ended on 10 May 1871, Wallach moved to Berlin and took a job at Aktien-Gesellschaft für Anilin-Fabrikation, a dyes and strains manufacturing company. He was unable to tolerate the fumes there and returned to the University of Bonn in 1872, where he remained until 1889.
Wallach was initially hired as an assistant in the organic laboratory. He later became a Privatdozent and was appointed Professor Extraordinary of Pharmacy in 1876.
Although he preferred chemistry, when the Chair of Pharmacology became vacant in 1879, Wallach was compelled to take it. He began working on amid chlorides and phosphorus pentachloride at some point and discovered imino-chlorides. He also worked on imide chlorides, amidines, and glyoxalines during this time period.
Meanwhile, Professor Kekulé stumbled across an old forgotten cupboard containing rows of bottles containing essential oils. He requested that Wallach examine them. Thus, Wallach entered a field that would later elevate him to prominence as a chemist and earn him the Nobel Prize in Chemistry.
He published his first article on essential oils in 1884. At the time, it was believed that the C10H16 group contained a variety of compounds such as citrene, carvene, cinene, cajuputene, eucalyptine, and hesperidine. He raised concerns about it in this publication.
He confirmed in 1885 that a large number of these elements were identical. He did, however, take many additional years to complete his studies. In 1909, he published his final paper.
Meanwhile, Wallach was appointed to the Wöhler Chair at Göttingen’s Chemical Institute in 1889. Simultaneously, he was appointed Director of the Institute. In 1915, he resigned from that position.
Significant Works
Wallach is most well-known for his research into the molecular structure of essential oils. He began by distilling various oils repeatedly to isolate their constituents and then studied their physical properties. Finally, he concluded that many of these oils are identical.
Additionally, he was able to isolate a group of aromatic compounds from these oils. Terpenes was the name he gave it. His experimentation lasted nearly fifteen years. He eventually published his findings in 1909 in a paper titled ‘Terpene und Campher’. His work laid the groundwork for the modern perfume industry.
Additionally, Wallach is renowned for his work on amid chlorides, azo dyes, and diazo compounds. Another significant work is his conversion of chloral to dichloroacetic acid.
Awards and Accomplishments
Wallach received the 1910 Nobel Prize in Chemistry “for his pioneering work in the field of alicyclic compounds.”
In 1912, the Royal Society of London awarded Wallach the Davy Medal “for his researches on the chemistry of essential oils and cyclo-olefines.”
In 1908, he was also awarded Honorary Fellowships by the Chemical Society, and in 1912, he was elected an Honorary Member of the Verein Deutscher Chemiker.
Wallach was awarded the Kaiserlicher Adlerorden III Klasse (Imperial Order of the Eagle) in 1911 and the Königlicher Kronorden II Klasse (Imperial Order of the Eagle) in 1915. (Royal Order of the Crown).
He also received Honorary Doctorates from the Universities of Manchester, Leipzig, and Braunschweig.
Personal History and Legacies
Otto Wallach remained a bachelor throughout his life, devoting his time and energy entirely to his work. He died of natural causes in Göttingen on 26 February 1931, at the age of 83. He was laid to rest in the Göttinger Stadtfriedhof.
The rule in organic chemistry that racemic crystals are denser than their chiral counterparts is referred to as ‘Wallach’s Rule’. Additionally, there is a ‘Wallach Rearrangement,’ a ‘Wallach Degradation,’ and a ‘Leuckart-Wallach reaction,’ all of which are named after Otto Wallach.
Estimated Net Worth
The estimated net worth of Otto is $1-$5 million.