Wittig (Wittig), Georg( German chemist, Nobel Prize in Chemistry, 1979)
Comments for Wittig (Wittig), Georg
Biography Wittig (Wittig), Georg
June 16, 1897, Mr.. - August 26, 1987
The German chemist Georg Friedrich Karl Wittig was born in Berlin, the family of Professor of Fine Arts Berlin University of Gustav Wittig and Martha (Dabrowski) Wittig. William graduated from high school in Kassel, he in 1916. enrolled in the University of Tц╪bingen, but was forced to interrupt their studies because he was called up for military service: there was a World War I. In 1920, Mr.. M. became a student at Marburg University, where he studied chemistry under Carl von Auwers. In 1923, Mr.. He received his doctorate. For several years, M. conducted research and teaching at the University of Marburg, as an assistant and lecturer, and in 1932. was appointed associate professor at the Technical University in Brunswick. Five years later, the scientist moved to work at the University of Freiburg for the post of extraordinary professor (associate professor).
in 1944. was promoted to full professor and was appointed Director of the Chemical Institute of the University of Tubingen, and, finally, 12 years later moved to the University of Heidelberg, where in 1967 he. became an honorary professor emeritus.
At the beginning of his scientific career in. interested in the precise mechanisms of certain reactions, . especially with the participation of free radicals and carbanions (negatively charged carbon atoms in organic molecules) as intermediate reaction products, . as well as certain types of molecular rearrangements,
. Development of these themes created a reputation as a scientist organic chemist with a rich imagination and skilled experimenter.
In 40-ies. V. set itself the task of creating molecules, in which 5 of organic groups are covalently bonded with the group V elements of the periodic table, such as nitrogen, phosphorus and arsenic. Despite the fact that the creation of such molecules was considered theoretically possible, no one has yet synthesized. Eventually. and his colleagues have solved this problem (it failed only the synthesis of nitrogen). In the process of research, scientists are faced with triggered their interest in compounds called ylides. In ylides quaternary salt group V elements (containing 4 organic group and halogen attached) rather than to purchase a fifth organic group, loses a proton from one organic group. In 1953, Mr.. V. found that such free ylides react with carbonyl compounds (aldehydes and ketones, whose molecules contain carbon-oxygen double bond). It carbanion ylides (devoid of proton carbon) is exchanged for the carbonyl oxygen atom. As a result of this process is formed olefin with a new carbon-carbon double bond instead of the carbonyl group. Accidentally made a discovery, now known as the Wittig reaction, possessed far greater research potential than the successful solution of the original task.
In the 20-ies. independently Hermann Staudinger and Carlo. Marvel has already undertaken significant preparatory work for this type of reactions. In fact, Staudinger described the first phosphorus ylides in 1919, Mr.. However, since most of their work was not published at that time, it is unlikely to have influenced conducted in. study. The reason for his success, VA, as it may seem strange to explain the limits of their knowledge about the work of predecessors, devoted to the study of this topic. And indeed, if in. knew about the results achieved by Marvel, it would have only compounds containing pentavalent phosphorus, and a new chemical reaction (Wittig reaction) would not have been opened. Ironically, Staudinger and B. were colleagues at the University of Freiburg in the early 40's. but by that time Staudinger has long ceased to work on derivatives of phosphorus and could not give in. new information in this field of research.
Wittig reaction of organic chemists have adopted immediately. Thanks to her they could now easily and securely connect dvuuglerodnye structure, using the appropriate alkyl halides and carbonyl compounds, and the one and the other can be easily obtained from different precursors. In addition, the reaction proceeded remarkably easy, gave a high yield, and while there had been no unintended molecular rearrangements. Until now, it is considered that this reaction is significantly superior to competing with her methods of olefin synthesis.
The usefulness of this reaction is further increased through further studies in. and a group of his colleagues in Tц╪bingen and Heidelberg. In the early 60-ies. appeared more than a hundred articles on the specific application of the Wittig reaction, to the mid-80's there were already thousands of. There are also many technical applications of this reaction.
In 1979. V. and Herbert W. Brown was awarded the Nobel Prize in Chemistry 'for the development of new methods of organic synthesis of boron-and phosphorus-containing compounds'. In his opening speech on behalf of the Royal Swedish Academy of Sciences Bendt Lindberg said: 'George's. did much for the development of organic chemistry ... Elegant method in. found wide application, for example, in the industrial synthesis of vitamin A '.
. Wittig reaction is priceless in the manufacture of complex pharmaceuticals such as synthetic vitamin A, derivatives of vitamin D, steroids and precursors of prostaglandin
. It is also used in the synthesis of pheromones for pest control.
In 1930. V. married Waltraud Ernst. They had two daughters. The wife of a scientist died in 1978
In. liked to go to the mountains with his friend Karl Ziegler and generally lead an active lifestyle. Students. said that the scientist had musical talent. Musical ability was at in. in childhood, and he could easily make an entirely different career, but the chemistry was his all-consuming passion. Even having gone into retirement, he continued to work as a supervisor of some groups of graduates, published his work. V. died at Heidelberg at the age of 90 years.
In. was a very respected scholar, and his work has received wide international recognition. In addition to the Nobel Prize, . among his awards included: Medal of Adolf von Bauer (1953) and Otto Hahn Prize (1967) Germanskogo Chemical Society, . Paul Karrer Medal for achievements in chemistry at Zurich University (1972) and Roger Adams Award of the American Chemical Society (1975),
. He was awarded honorary degrees from universities in Paris, Tц╪bingen and Hamburg.