| August Wilhelm von Hofmann | |
 August Wilhelm von Hofmann | |
| Born | April 8, 1818 Giessen, Germany |
|---|---|
| Died | May 5, 1892 (aged 74) Berlin, Germany |
| Residence | Germany |
| Nationality | German |
| Fields | Chemist |
| Institutions | University of Bonn Royal College of Chemistry Berlin University |
| Alma mater | University of Göttingen |
| Doctoral advisor | Justus von Liebig |
| Doctoral students | Richard Abegg Adolf Pinner Fritz Haber Karl Friedrich von Auwers Rudolf Hugo Nietzki Ferdinand Tiemann Eugen Bamberger |
| Known for | Hofmann rearrangement Hofmann elimination Hofmann-Löffler reaction |
August Wilhelm von Hofmann (April 8, 1818 – May 5, 1892) was a German chemist. Events 217 - Roman Emperor Caracalla is Assassinated (and succeeded by his Praetorian Year 1818 ( MDCCCXVIII) was a Common year starting on Thursday (link will display the full calendar of the Gregorian Calendar (or a Common Gießen (ˈgiːsən is a town in the German federal state ( Bundesland) of Hessen, capital of both the district of Gießen and the administrative Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. Events 553 - The Second Council of Constantinople begins 1215 - Rebel Barons renounce their allegiance to King John Year 1892 ( MDCCCXCII) was a Leap year starting on Friday (link will display the full calendar of the Gregorian Calendar (or a Leap year Berlin is the capital city and one of sixteen states of Germany. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. A chemist is a Scientist trained in the Science of Chemistry. The University of Bonn ( German: Rheinische Friedrich-Wilhelms-Universität Bonn) is a public research university located in Bonn, Germany The Royal College of Chemistry ( RCC) was a college originally based on Oxford Street in central London, England. For other universities in Berlin see List of Universities in Berlin. Alma mater is Latin for "nourishing mother" It was used in Ancient Rome as a title for the mother Goddess, and in Medieval The University of Göttingen ( German: Georg-August-Universität Göttingen) is a University in the city of Göttingen, Germany. A doctorate is an Academic degree that indicates the highest level of academic achievement Justus von Liebig ( May 12, 1803 &ndash April 18, 1873) was a German Chemist Richard Wilhelm Heinrich Abegg (1869 &ndash 1910 was a German Chemist and pioneer of valence theory. Adolf Pinner ( August 31 1842, Wronki, Provinz Posen - May 21, 1909, Berlin) was a German chemist Fritz Haber (9 December 1868 &ndash 29 January 1934 was a German chemist, who received the Nobel Prize in Chemistry in 1918 for his development for Karl Friedrich von Auwers was a German chemist and the academic adviser of Karl Ziegler and Georg Wittig at the University of Marburg. Johann Karl Wilhelm Ferdinand Tiemann was a German chemist and together with Reimer discoverer of the Reimer-Tiemann reaction. Eugen Bamberger was a German chemist and discoverer of the Bamberger rearrangement. The Hofmann rearrangement is the organic reaction of a primary Amide to a primary Amine with one fewer Carbon atom Hofmann elimination (also known as exhaustive methylation) is a process where an Amine is reacted to create a tertiary amine and an Alkene by treatment The Hofmann-Löffler reaction or Hofmann-Löffler-Freytag Reaction is an Organic reaction is which a Haloamine is converted to a cyclic Amine Events 217 - Roman Emperor Caracalla is Assassinated (and succeeded by his Praetorian Year 1818 ( MDCCCXVIII) was a Common year starting on Thursday (link will display the full calendar of the Gregorian Calendar (or a Common Events 553 - The Second Council of Constantinople begins 1215 - Rebel Barons renounce their allegiance to King John Year 1892 ( MDCCCXCII) was a Leap year starting on Friday (link will display the full calendar of the Gregorian Calendar (or a Leap year Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. A chemist is a Scientist trained in the Science of Chemistry.
Biography
Hofmann was born at Gießen, Grand Duchy of Hesse. Gießen (ˈgiːsən is a town in the German federal state ( Bundesland) of Hessen, capital of both the district of Gießen and the administrative The Grand Duchy of Hesse (Großherzogtum Hessen was a former state that existed in modern-day Germany. Not intending originally to devote himself to physical science, he first took up the study of law and philology at Göttingen. Physical science is an encompassing term for the branches of Natural science and Science that study non-living systems in contrast to the biological sciences Law is a system of rules enforced through a set of Institutions used as an instrument to underpin civil obedience politics economics and society See Comparative linguistics for the narrower field of "comparative philology" Göttingen ( ˈgœtɪŋən, Low German: Chöttingen is a College town in Lower Saxony, Germany. But he then turned to chemistry, and studied under Justus von Liebig at University of Giessen. Chemistry (from Egyptian kēme (chem meaning "earth") is the Science concerned with the composition structure and properties Justus von Liebig ( May 12, 1803 &ndash April 18, 1873) was a German Chemist The University of Gießen (German Universität Gießen) is officially called Justus Liebig-Universität Gießen after its most famous member When, in 1845, a school of practical chemistry was started in London, under the style of the Royal College of Chemistry, Hofmann, largely through the influence of the Prince Consort, was appointed its first director. London ( ˈlʌndən is the capital and largest urban area in the United Kingdom. The Royal College of Chemistry ( RCC) was a college originally based on Oxford Street in central London, England. A prince consort, generally speaking is a common term for the husband of a Queen regnant, unless he himself also is a king in his own right It was with some hesitation that he, then a Privatdozent at Bonn, accepted the position, which may well have seemed rather a precarious one; but the difficulty was removed by his appointment as extraordinary professor at Bonn, with leave of absence for two years, so that he could resume his career in Germany if his English one proved unsatisfactory. Private docent (abbreviates PD or Priv-Doz) is a title conferred in some European university systems especially in German -speaking countries Bonn is the 19th largest city in Germany. Located about 20 kilometres south of Cologne on the river Rhine in the Federal State of North Rhine-Westphalia Fortunately the college was more or less successful, owing largely to his enthusiasm and energy, and many of the men who were trained there subsequently made their mark in chemical history. In 1864 he returned to Bonn, and in the succeeding year he was selected to succeed Eilhard Mitscherlich as professor of chemistry and director of the laboratory in Berlin University. Eilhard Mitscherlich (7 January 1794 &ndash 28 August 1863 was a German Chemist, who is perhaps best remembered today for his law of isomorphism (1819 which states For other universities in Berlin see List of Universities in Berlin.
Hofmann's work covered a wide range of organic chemistry. Organic chemistry is a discipline within Chemistry which involves the scientific study of the structure properties composition reactions, and preparation His first research, carried out in Liebig's laboratory at Giessen, was on coal-tar and his investigation of the organic bases in coal-gas naphtha established the nature of aniline. Coal tar is a brown or black liquid of high Viscosity, which smells of Naphthalene and Aromatic hydrocarbons Coal tar is among the by-products when coal Naphtha normally refers to a number of different flammable liquid mixtures of hydrocarbons i Aniline, phenylamine or aminobenzene is an Organic compound with the formula C6H7N This substance he used to refer to as his first love, and it was a love to which he remained faithful throughout his life. His perception of the analogy between it and ammonia led to his famous work on the amines and ammonium bases and the allied organic phosphorus compounds while his researches on rosaniline, which he first prepared, formed the first of a series of investigations on coloring matter which only ended with quinoline red in 1887. Ammonia is a compound with the formula N[[hydrogen H3]] It is normally encountered as a Gas with a characteristic pungent Odor Phosphorus, (ˈfɒsfərəs is the Chemical element that has the symbol P and Atomic number 15
The Hofmann rearrangement and Hofmann elimination reaction bear his namesake. The Hofmann rearrangement is the organic reaction of a primary Amide to a primary Amine with one fewer Carbon atom Hofmann elimination (also known as exhaustive methylation) is a process where an Amine is reacted to create a tertiary amine and an Alkene by treatment Hofmann was also the first to introduce molecular models into his public lectures around 1860, following the earlier (1855) suggestion by his colleague William Odling that carbon is tetravalent. Molecular modelling is a collective term that refers to theoretical methods and computational techniques to model or mimic the behaviour of Molecules The techniques William Odling (1829 - 1921 was an English chemist who contributed to the development of the Periodic table. Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 In Chemistry, a tetravalence is the state of an Atom with four Electrons available for covalent chemical bonding in its valence This legacy is still remembered nowadays by continuing use of Hofmann's colour scheme: (carbon = black, hydrogen = white, nitrogen = blue, oxygen = red, chlorine = green, sulfur = yellow, as cited by W. Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Chlorine (ˈklɔriːn from the Greek word 'χλωρóς' ( khlôros, meaning 'pale green' is the Chemical element with Atomic number 17 and Sulfur or sulphur (ˈsʌlfɚ see spelling below) is the Chemical element that has the Atomic number 16 D. Ollis, "Models and molecules", Proceedings of the Royal Institution of Great Britain, (1972), 45, 1-31). The models look rather odd nowadays, primarily because Hofmann had them built so that the carbon was planar, and smaller in size than the hydrogen! (it was Loschmidt in 1861 who probably first appreciated the differing sizes of different atoms). Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Jan or Johann Josef Loschmidt ( March 15 1821 - July 8 1895) who referred to himself mostly as 'Josef' (omitting his first name It was not until 1874, when Jacobus Henricus van't Hoff and (independently) Joseph Achille Le Bel suggested carbon can be tetrahedral, that molecular models assumed their modern appearance. Jacobus Henricus van 't Hoff ( August 30, 1852 &ndash March 1, 1911) was a Dutch physical and organic chemist Joseph Achille Le Bel (1847–1930 was a French Chemist, who was best known for his work in Stereochemistry. A tetrahedron (plural tetrahedra) is a Polyhedron composed of four triangular faces three of which meet at each vertex. A molecular model, in this article is a physical model that represents Molecules and their processes
William Henry Perkin was a student of his at the Royal College of Chemistry in London, when he discovered the first aniline dye, mauveine. Sir William Henry Perkin, FRS ( March 12, 1838 July 14, 1907) was an English Chemist best known for his Aniline, phenylamine or aminobenzene is an Organic compound with the formula C6H7N Mauveine, also known as Aniline Purple and Perkin's mauve, was the first synthetic organic Dye.
See also
References
- Theodore A. In Chemistry, the history of the Molecule traces the origins of the concept or idea of the existence of strong chemical bonds between two or more Atoms Alston (2003). "The Contributions of A. W. Hofmann". Anesthesia Analgesia 96: 622-625.
- John J. Beer (1960). "A. W. Hofmann and the Founding of the Royal College of Chemistry". Journal of Chemical Education 37 (5): 248 – 251.
- Christoph Meinel (1992). "August Wilhelm Hofmann - Reigning Chemist-in-Chief". Angewandte Chemie International Edition in English 31 (10): 1265-1282. Angewandte Chemie is a weekly Peer-reviewed Chemistry journal that covers all disciplines of chemistry doi:. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.
- William Henry Perkin (1896). Sir William Henry Perkin, FRS ( March 12, 1838 July 14, 1907) was an English Chemist best known for his "The origin of the coal-tar colour industry, and the contributions of Hofmann and his pupils". Journal Chemical Society Transaction 69: 596. doi:. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.
- Anthony S. Travis (1992). "August Wilhelm Hofmann (1818–1892)". Endeavour 16 (2): 59-65. doi:. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.
- This article incorporates text from the Encyclopædia Britannica Eleventh Edition, a publication now in the public domain. The Encyclopædia Britannica Eleventh Edition (1910–1911 is a 29-volume reference work that marked the beginning of the Encyclopædia Britannica The public domain is a range of abstract materials &ndash commonly referred to as Intellectual property &ndash which are not owned or controlled by anyone
| Persondata | |
|---|---|
| NAME | Hofmann, August Wilhelm von |
| ALTERNATIVE NAMES | |
| SHORT DESCRIPTION | German Chemist |
| DATE OF BIRTH | April 8, 1818 |
| PLACE OF BIRTH | Giessen, Germany |
| DATE OF DEATH | May 5, 1892 |
| PLACE OF DEATH | Berlin, Germany |
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