Hans von Pechmann

Infobox_Scientist
name = Hans von Pechmann


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caption =
birth_date = April 1 1850
birth_place =
residence = Germany
nationality = German
death_date = death date and age|1902|4|19|1850|4|1
death_place =
field = organic chemistry
work_institution = University of Munich University of Tübingen
alma_mater = University of Greifswald
doctoral_advisor = Heinrich Limpricht
doctoral_students = William Hobson Mills Julius B. Cohen
known_for = Pechmann condensation Diazomethane
prizes =
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footnotes =

Hans von Pechmann (1850 - 1902) was a German chemist, renowned for his discovery of diazomethane, [cite journal
author= H. v. Pechmann
title = Ueber Diazomethan
journal = Berichte der deutschen chemischen Gesellschaft
year = 1894
volume = 27
issue = 2
pages = 1888–1891
doi = 10.1002/cber.189402702141] [cite journal
author= H. v. Pechmann
title = Ueber Diazomethan
journal = Berichte der deutschen chemischen Gesellschaft
year = 1895
volume = 28
issue = 1
pages = 855–861
doi = 10.1002/cber.189502801189] Pechmann condensation [cite journal
author= H. v. Pechmann, Carl Duisberg
title = Ueber die Verbindungen der Phenole mit Acetessigäther
journal = Berichte der deutschen chemischen Gesellschaft
year = 1883
volume = 16
issue = 1
pages = 2119–2128
doi = 10.1002/cber.188301602117] [cite journal
author= H. v. Pechmann
title = Neue Bildungsweise der Cumarine. Synthese des Daphnetins
journal = Berichte der deutschen chemischen Gesellschaft
year = 1884
volume = 17
issue = 1
pages = 929–936
doi = 10.1002/cber.188401701248] and Pechmann pyrazole synthesis [cite journal
author= H. v. Pechmann
title = Pyrazol aus Acetylen und Diazomethan
journal = Berichte der deutschen chemischen Gesellschaft
year = 1898
volume = 31
issue = 3
pages = 2950–2951
doi = 10.1002/cber.18980310363] . He also first prepared 1,2-diketones (e.g., diacetyl), acetonedicarboxylic acid, methylglyoxal and diphenyltriketone; established the symmetrical structure of anthraquinone.

Von Pechmann also discovered polyethylene plastics serendipitously, when accidentally heating diazomethane.

After studying with Heinrich Limpricht at the University of Greifswald he became Professor at the University of Munich till 1895. He was professor at the University of Tübingen from 1895 till his death in 1902.

References

* Partington, J. R. "A History of Chemistry". Macmillan: 1964; vol. 4, p. 838-839.