Ernst Otto Beckmann
Encyclopedia
Ernst Otto Beckmann was a German chemist who is remembered for his invention of the Beckmann differential thermometer
and for his discovery of the Beckmann rearrangement
.
, Germany
on July 4, 1853 to a family headed by Johannes Friedrich Wilhelm Beckmann, a manufacturer. The elder Beckmann's factory produced mineral dyes, pigments, abrasives, and polishing material, and it was there that the younger Beckmann conducted his early chemical experiments. At the age of 17, Beckmann was persuaded by his father to study pharmacy instead of chemistry, and so in 1870 an apprenticeship was arranged in Elberfeld
. However, Beckmann did not enjoy the working conditions and returned home, to his father's disappointment. Told that a chemical career would be difficult if could not handle an apprenticeship in pharmacy, Beckmann then returned to Elberfeld to finish his work. He also worked at pharmacies in Arolsen, Burg an der Wupper, Leipzig
, and Cologne
.
To improve his theoretical skills, in 1874 Beckmann joined the school of Remigius Fresenius in Wiesbaden
, and moved to the University of Leipzig
the following year when Fresenius became a professor there. At Leipzig, Beckmann came into contact with the renowned chemist Hermann Kolbe. Although Beckmann wanted to study chemistry, he finished his studies with Fresenius, passing his pharmacy examination in 1877. He then joined Kolbe, and his assistant, Ernst von Meyer, and started work on the oxidation of dialkyle sulfides. For this research Beckmann received his PhD in July 1878.
After a year of voluntary military service, as a pharmacist, Beckmann began studying toxicology
at the TU Braunschweig with Robert Otto, receiving his habilitation
in 1882. He returned to Leipzig and wanted to work as a lecturer with Kolbe, but the habilitation at a technical university was not a sufficient qualification for such a position. For a habilitation at a university an abitur
from a humanistic gymnasium was necessary, and for this Latin
language skills were obligatory. Therefore Beckmann again began studying, and was able to complete the necessary exams in Latin, Greek language
, and history in 1883, and again work at Leipzig. Kolbe died in 1884 and was succeeded by one of his critics, Johannes Wislicenus
. This might have threatened Beckmann's academic career, but contrary to expectations the two chemists became colleagues and friends.
Beckmann tried to apply an already-known reaction to discriminate between aldehyde
s and ketone
s. The reaction involved the use of hydroxylamine
to convert benzophenone
into an oxime
. Treating this oxime with phosphorus pentachloride converted it into a substance already characterized by Wallach
. This reaction is now known as the Beckmann rearrangement
.
In 1887 Wilhelm Ostwald
moved to Leipzig, and physical chemistry
then became a focus of Beckmann's work, as he served as an assistant to Ostwald. Beckmann used the methods of ebullioscopy
(boiling-point elevation) and cryoscopy (freezing-point depression) to determine the molecular masses of several substances. These measurements required a careful determination of temperature differences, as opposed to absolute values, and to accomplish them Beckmann invented the differential thermometer that now carries his name (Beckmann thermometer
). For this work he altered the methods of François-Marie Raoult
, and the improvement was sufficiently great that Beckmann's method, and the associated equipment, became standard in chemical laboratories. However, by the end of the twentieth century these colligative-property techniques had been largely superseded by molecular mass determinations using electronic instrumentation.
It was also during this time of work with Ostwald at Leipzig that Beckmann discovered the sodium and benzophenone react in dry ether to produce a blue solution, now known to be due to ketyl-radical formation. This reactions remains a standard one among chemists seeking to judge the anhydrous state of solvents.
Beckmann left Leipzig to spend a year working at the University of Gießen and then served as a professor at the University of Erlangen, but in 1897 he was back in Leipzig for the third time, as Director of the Laboratory of Applied Chemistry. In 1912 he was asked to head a division of the newly-founded Kaiser Wilhelm Institute for Chemistry. He accepted the offer, moved to Berlin on April 1, 1912, and there he remained until his retirement from the institute in October 1921. Afterwards he was allowed to use a laboratory at the institute, and he worked again on the Beckmann rearrangement
and measurements of physical properties of solutions.
During the First World War, Beckmann had conducted research on lupin beans to make them available to feed animals. It was his practice to taste water removed from lupins as a way to determine if toxic bitter portions had been removed by aqueous extractions. It is speculated that this practice might have severely damaged his health, for by his retirement he was quite ill.
Beckmann died in Berlin
on July 12, 1923 and was buried at Dahlem
.
Beckmann thermometer
A Beckmann thermometer is a device used to measure small differences of temperature, but not absolute temperature values. It was invented by Ernst Otto Beckmann , a German chemist, for his measurements of colligative properties in 1905...
and for his discovery of the Beckmann rearrangement
Beckmann rearrangement
The Beckmann rearrangement, named after the German chemist Ernst Otto Beckmann , is an acid-catalyzed rearrangement of an oxime to an amide...
.
Scientific work
Ernst Otto Beckmann was born in SolingenSolingen
Solingen is a city in North Rhine-Westphalia, Germany. It is located on the northern edge of the region called Bergisches Land, south of the Ruhr area, and with a 2009 population of 161,366 is the second largest city in the Bergisches Land...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
on July 4, 1853 to a family headed by Johannes Friedrich Wilhelm Beckmann, a manufacturer. The elder Beckmann's factory produced mineral dyes, pigments, abrasives, and polishing material, and it was there that the younger Beckmann conducted his early chemical experiments. At the age of 17, Beckmann was persuaded by his father to study pharmacy instead of chemistry, and so in 1870 an apprenticeship was arranged in Elberfeld
Elberfeld
Elberfeld is a municipal subdivision of the German city of Wuppertal; it was an independent town until 1929.-History:The first official mentioning of the geographic area on the banks of today's Wupper River as "elverfelde" was in a document of 1161...
. However, Beckmann did not enjoy the working conditions and returned home, to his father's disappointment. Told that a chemical career would be difficult if could not handle an apprenticeship in pharmacy, Beckmann then returned to Elberfeld to finish his work. He also worked at pharmacies in Arolsen, Burg an der Wupper, Leipzig
Leipzig
Leipzig Leipzig has always been a trade city, situated during the time of the Holy Roman Empire at the intersection of the Via Regia and Via Imperii, two important trade routes. At one time, Leipzig was one of the major European centres of learning and culture in fields such as music and publishing...
, and Cologne
Cologne
Cologne is Germany's fourth-largest city , and is the largest city both in the Germany Federal State of North Rhine-Westphalia and within the Rhine-Ruhr Metropolitan Area, one of the major European metropolitan areas with more than ten million inhabitants.Cologne is located on both sides of the...
.
To improve his theoretical skills, in 1874 Beckmann joined the school of Remigius Fresenius in Wiesbaden
Wiesbaden
Wiesbaden is a city in southwest Germany and the capital of the federal state of Hesse. It has about 275,400 inhabitants, plus approximately 10,000 United States citizens...
, and moved to the University of Leipzig
University of Leipzig
The University of Leipzig , located in Leipzig in the Free State of Saxony, Germany, is one of the oldest universities in the world and the second-oldest university in Germany...
the following year when Fresenius became a professor there. At Leipzig, Beckmann came into contact with the renowned chemist Hermann Kolbe. Although Beckmann wanted to study chemistry, he finished his studies with Fresenius, passing his pharmacy examination in 1877. He then joined Kolbe, and his assistant, Ernst von Meyer, and started work on the oxidation of dialkyle sulfides. For this research Beckmann received his PhD in July 1878.
Toxicology
Toxicology is a branch of biology, chemistry, and medicine concerned with the study of the adverse effects of chemicals on living organisms...
at the TU Braunschweig with Robert Otto, receiving his habilitation
Habilitation
Habilitation is the highest academic qualification a scholar can achieve by his or her own pursuit in several European and Asian countries. Earned after obtaining a research doctorate, such as a PhD, habilitation requires the candidate to write a professorial thesis based on independent...
in 1882. He returned to Leipzig and wanted to work as a lecturer with Kolbe, but the habilitation at a technical university was not a sufficient qualification for such a position. For a habilitation at a university an abitur
Abitur
Abitur is a designation used in Germany, Finland and Estonia for final exams that pupils take at the end of their secondary education, usually after 12 or 13 years of schooling, see also for Germany Abitur after twelve years.The Zeugnis der Allgemeinen Hochschulreife, often referred to as...
from a humanistic gymnasium was necessary, and for this Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
language skills were obligatory. Therefore Beckmann again began studying, and was able to complete the necessary exams in Latin, Greek language
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
, and history in 1883, and again work at Leipzig. Kolbe died in 1884 and was succeeded by one of his critics, Johannes Wislicenus
Johannes Wislicenus
Johannes Wislicenus was a German chemist, most famous for his work in early stereochemistry.-Biography:...
. This might have threatened Beckmann's academic career, but contrary to expectations the two chemists became colleagues and friends.
Beckmann tried to apply an already-known reaction to discriminate between aldehyde
Aldehyde
An aldehyde is an organic compound containing a formyl group. This functional group, with the structure R-CHO, consists of a carbonyl center bonded to hydrogen and an R group....
s and ketone
Ketone
In organic chemistry, a ketone is an organic compound with the structure RCR', where R and R' can be a variety of atoms and groups of atoms. It features a carbonyl group bonded to two other carbon atoms. Many ketones are known and many are of great importance in industry and in biology...
s. The reaction involved the use of hydroxylamine
Hydroxylamine
Hydroxylamine is an inorganic compound with the formula NH2OH. The pure material is a white, unstable crystalline, hygroscopic compound. However, hydroxylamine is almost always provided and used as an aqueous solution. It is used to prepare oximes, an important functional group. It is also an...
to convert benzophenone
Benzophenone
Benzophenone is the organic compound with the formula 2CO, generally abbreviated Ph2CO. Benzophenone is a widely used building block in organic chemistry, being the parent diarylketone.-Uses:...
into an oxime
Oxime
An oxime is a chemical compound belonging to the imines, with the general formula R1R2C=NOH, where R1 is an organic side chain and R2 may be hydrogen, forming an aldoxime, or another organic group, forming a ketoxime. O-substituted oximes form a closely related family of compounds...
. Treating this oxime with phosphorus pentachloride converted it into a substance already characterized by Wallach
Wallach
Wallach is a word of Germanic origin:* meaning a gelding* referring especially to Latin people, particularly Romanians and Italians. See the history of the term Vlach.- Family name :* Eli Wallach , American actor...
. This reaction is now known as the Beckmann rearrangement
Beckmann rearrangement
The Beckmann rearrangement, named after the German chemist Ernst Otto Beckmann , is an acid-catalyzed rearrangement of an oxime to an amide...
.
In 1887 Wilhelm Ostwald
Wilhelm Ostwald
Friedrich Wilhelm Ostwald was a Baltic German chemist. He received the Nobel Prize in Chemistry in 1909 for his work on catalysis, chemical equilibria and reaction velocities...
moved to Leipzig, and physical chemistry
Physical chemistry
Physical chemistry is the study of macroscopic, atomic, subatomic, and particulate phenomena in chemical systems in terms of physical laws and concepts...
then became a focus of Beckmann's work, as he served as an assistant to Ostwald. Beckmann used the methods of ebullioscopy
Boiling-point elevation
Boiling-point elevation describes the phenomenon that the boiling point of a liquid will be higher when another compound is added, meaning that a solution has a higher boiling point than a pure solvent. This happens whenever a non-volatile solute, such as a salt, is added to a pure solvent, such...
(boiling-point elevation) and cryoscopy (freezing-point depression) to determine the molecular masses of several substances. These measurements required a careful determination of temperature differences, as opposed to absolute values, and to accomplish them Beckmann invented the differential thermometer that now carries his name (Beckmann thermometer
Beckmann thermometer
A Beckmann thermometer is a device used to measure small differences of temperature, but not absolute temperature values. It was invented by Ernst Otto Beckmann , a German chemist, for his measurements of colligative properties in 1905...
). For this work he altered the methods of François-Marie Raoult
François-Marie Raoult
François-Marie Raoult was a French chemist who conducted research into the behavior of solutions, especially their physical properties.- Life and work :Raoult was born at Fournes, in the département of Nord...
, and the improvement was sufficiently great that Beckmann's method, and the associated equipment, became standard in chemical laboratories. However, by the end of the twentieth century these colligative-property techniques had been largely superseded by molecular mass determinations using electronic instrumentation.
It was also during this time of work with Ostwald at Leipzig that Beckmann discovered the sodium and benzophenone react in dry ether to produce a blue solution, now known to be due to ketyl-radical formation. This reactions remains a standard one among chemists seeking to judge the anhydrous state of solvents.
Beckmann left Leipzig to spend a year working at the University of Gießen and then served as a professor at the University of Erlangen, but in 1897 he was back in Leipzig for the third time, as Director of the Laboratory of Applied Chemistry. In 1912 he was asked to head a division of the newly-founded Kaiser Wilhelm Institute for Chemistry. He accepted the offer, moved to Berlin on April 1, 1912, and there he remained until his retirement from the institute in October 1921. Afterwards he was allowed to use a laboratory at the institute, and he worked again on the Beckmann rearrangement
Beckmann rearrangement
The Beckmann rearrangement, named after the German chemist Ernst Otto Beckmann , is an acid-catalyzed rearrangement of an oxime to an amide...
and measurements of physical properties of solutions.
Personal life
Beckmann married Bertha Oertel on March 20, 1887 and had one daughter and two sons with her.During the First World War, Beckmann had conducted research on lupin beans to make them available to feed animals. It was his practice to taste water removed from lupins as a way to determine if toxic bitter portions had been removed by aqueous extractions. It is speculated that this practice might have severely damaged his health, for by his retirement he was quite ill.
Beckmann died in Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
on July 12, 1923 and was buried at Dahlem
Dahlem (Berlin)
Dahlem is a locality of the Steglitz-Zehlendorf borough in southwestern Berlin. Until Berlin's 2001 administrative reform it was a part of the former borough of Zehlendorf. Dahlem is one of the most affluent parts of the city and home to the main campus of the Free University of Berlin with the...
.
See also
- Mass spectrometryMass spectrometryMass spectrometry is an analytical technique that measures the mass-to-charge ratio of charged particles.It is used for determining masses of particles, for determining the elemental composition of a sample or molecule, and for elucidating the chemical structures of molecules, such as peptides and...
- Beckmann thermometer (from the German Wikipedia)
External links
(Drawings of some of Beckmann's equipment)- Brief Beckmann biography by Colin Russell, Royal Society of Chemistry, 2003
- Brief biographical material
- German Wikipedia's entry for Beckmann