Vladimir Markovnikov

Vladimir Vasilyevich Markovnikov

Late 19th-century photograph of Marknovnikov.
Born December 22, 1837
Knyaginino, Nizhny Novgorod Governorate, Russian Empire
Died February 11, 1904 (aged 66)
Saint Petersburg, Russian Empire
Institutions University of Kazan
University of Saint Petersburg
University of Odessa
Alma mater University of Kazan
Doctoral advisor Alexander Butlerov

Vladimir Vasilyevich Markovnikov (Russian: Влади́мир Васи́льевич Марко́вников), also spelled as Markownikoff[1] (December 22, 1837 – February 11, 1904), was a Russian chemist.

Early life and education

Markovnikov studied economics at the at the University of Kazan; during his studies, under the Russian cameral system, he also studied chemistry.

After graduating, he became an assistant of Alexander Butlerov at the Kazan and then the Saint Petersburg.

In 1860, he went to Germany for two years where he studied under Richard Erlenmeyer and Hermann Kolbe.

Following his return to Russia, Markovnikov received his Ph.D. in 1869 and succeeded to Butlerov's professorship at the University of Kazan.

Career

After a conflict with that university, Markovnikov was appointed professor at the University of Odessa in 1871 and, two years later, at the University of Moscow, where he stayed the rest of his career.

Work

Markovnikov is best known for Markovnikov's rule, elucidated in 1869 to describe addition reactions of H-X to alkenes. According to this rule, the nucleophilic X- adds to the carbon atom with fewer hydrogen atoms, while the proton adds to the carbon atom with more hydrogen atoms bonded to it. Thus, hydrogen chloride (HCl) adds to propene, CH3-CH=CH2 to produce 2-chloropropane CH3CHClCH3 rather than the isomeric 1-chloropropane CH3CH2CH2Cl.[2] The rule is useful in predicting the molecular structures of products of addition reactions. Why hydrogen bromide exhibited both Markovnikov as well as reversed-order, or anti-Markovnikov, addition, however, was not understood until Morris S. Kharasch offered an explanation in 1933.

Hughes has discussed the reasons for Markovnikov's lack of recognition during his lifetime. [3] Although he published mostly in Russian which was not understood by most Western European chemists, the 1870 article in which he first stated his rule was written in German. However the rule was included in a 4-page addendum to a 26-page article on isomeric butyric acids, and based on very slight experimental evidence even by the standards of the time. Hughes concludes that the rule was an inspired guess, unjustified by the evidence of the time, but which turned out later to be correct (in most cases).

Markovnikov also contributed to organic chemistry by finding carbon rings with more than six carbon atoms, a ring with four carbon atoms in 1879, and a ring with seven in 1889.

Markovnikov also showed that butyric and isobutyric acids have the same chemical formula (C4H8O2) but different structures; i.e., they are isomers.

References

  1. ↑ Zerong, Wang. "Markownikoff Rule and Anti-Markownikoff Rule". Comprehensive Organic Name Reactions and Reagents 411: 1833–1837. doi:10.1002/9780470638859.conrr411.
  2. ↑ Markownikoff, W. (1870). "Ueber die Abhängigkeit der verschiedenen Vertretbarkeit des Radicalwasserstoffs in den isomeren Buttersäuren". Annalen der Pharmacie (in German) 153 (1): 228–259. doi:10.1002/jlac.18701530204.
  3. ↑ Hughes, Peter (2006). "Was Markovnikov's Rule an Inspired Guess?". The Journal of Chemical Education 83 (8): 1152–1154. Bibcode:2006JChEd..83.1152H. doi:10.1021/ed083p1152.

External links

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