Hans Finkelstein (17 May 1885,

Leipzig Leipzig (, ; ; Upper Saxon: ; ) is the most populous city in the States of Germany, German state of Saxony. The city has a population of 628,718 inhabitants as of 2023. It is the List of cities in Germany by population, eighth-largest city in Ge ...

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- December 1938) was a German

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a graduated scientist trained in the study of chemistry, or an officially enrolled student in the field. Chemists study the composition of ...

. He is particularly known for the

Finkelstein reaction The Finkelstein reaction, named after the German chemist Hans Finkelstein, is a type of SN2 reaction (substitution nucleophilic bimolecular reaction) that involves the exchange of one halogen atom for another. It is an equilibrium reaction, bu ...

developed by and named after him.

Biography

Hans Finkelstein came from a liberal

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family and joined the

Protestant Church Protestantism is a branch of Christianity that emphasizes justification of sinners through faith alone, the teaching that salvation comes by unmerited divine grace, the priesthood of all believers, and the Bible as the sole infallible sourc ...

when he was 10 years old. He studied chemistry like his father Berthold Finkelstein, one of

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's first chemists. After studying in

and

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he worked on his doctoral thesis with

Johannes Thiele Johannes Thiele may refer to: *Johannes Thiele (zoologist) *Johannes Thiele (chemist) {{hndis, Thiele, Johannes ...

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from 1906, submitting it in 1909. Finkelstein continued his scientific work as assistant to Prof. Thiele until 1912. During this time he also translated scientific books into German with his father. In 1912 Finkelstein transitioned from university to industry as head of the research department at

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. He filed some patents over the years. In 1912, Finkelstein married Annemarie Bruns. Together they had three children. In November 1938 shortly after the ''

Kristallnacht ( ) or the Night of Broken Glass, also called the November pogrom(s) (, ), was a pogrom against Jews carried out by the Nazi Party's (SA) and (SS) paramilitary forces along with some participation from the Hitler Youth and German civilia ...

'' and the subsequent ''Decree on the Exclusion of Jews from German Economic Life'', Finkelstein was forced to resign from his position in the company and to surrender his passport due to his Jewish descent. In December 1938 he did not see a future for himself and his life ended under tragic circumstances.

Work

Hans Finkelstein is well known in synthetic organic chemistry for the Finkelstein reaction, developed by him during his doctoral studies and published as a paper in 1910. The reaction describes the substitution of one type of halogen present in a

halocarbon Halocarbon compounds are chemical compounds in which one or more carbon atoms are linked by covalent bonds with one or more halogen atoms (fluorine, chlorine, bromine or iodine – ) resulting in the formation of organofluorine compounds, or ...

by another type of halogen. This process has been employed successfully in particular for the formation of organoiodine compounds among others.

References

{{DEFAULTSORT:Finkelstein, Hans 20th-century German chemists 19th-century German Jews German Protestants 1885 births 1938 deaths Scientists from Leipzig