Rainer Ludwig Claisen 1920802 204616247 2008-04-10T03:41:17Z Dassiebtekreuz 3805691 '''Rainer Ludwig Claisen''' ([[January 14]], [[1851]] – [[January 5]], [[1930]]) was a famous [[Germany|German]] [[chemist]] best known for his work with condensations of [[carbonyl]]s and [[sigmatropic rearrangement]]s. He was born in [[Cologne]] as the son of a [[jurist]] and studied chemistry at the university of [[Bonn]] ([[1869]]), where he became a member of [[K.St.V. Arminia]]. He served in the [[army]] as a male nurse in [[1870]]-[[1871]] and continued his studies at [[Georg August University of Göttingen|Göttingen University]]. He returned to the [[University of Bonn]] in [[1872]] and started his [[academic]] career at the same university in [[1874]]. He died in [[1930]] in [[Godesberg am Rhein]] (near [[Bonn]]). ==Career== '''Claisen's professional career:''' {| {{wikitable}} width="100%" |- | style="text-align:center;width:10%;" | '''[[1874]]''' | [[Doctorate|Promotion]] at the [[University of Bonn]]; position at [[Kekule|Kekulé's]] laboratory |- | style="text-align:center;width:10%;" | '''[[1878]]''' | [[Habilitation]] as [[Privatdozent]] at the University of Bonn |- | style="text-align:center;width:10%;" | '''[[1882]]''' | Worked with [[Henry Enfield Roscoe|Henry Roscoe]] and [[Carl Schorlemmer]] at [[Owens College]], [[Manchester]] (until [[1885]]) |- | style="text-align:center;width:10%;" | '''[[1886]]''' | Worked at the laboratory of [[Adolf von Baeyer|von Baeyer]] ([[University of Munich]]) |- | style="text-align:center;width:10%;" | '''[[1887]]''' | [[Habilitation]] as [[Privatdozent]] at the University of Munich |- | style="text-align:center;width:10%;" | '''[[1890]]''' | Position as [[Professor|Professor ordinarius]] of [[organic chemistry]] at [[Technische Hochschule|TH]] [[Aachen]] |- | style="text-align:center;width:10%;" | '''[[1897]]''' | Position as [[Professor|Professor ordinarius]] of [[chemistry]] at the [[University of Kiel]] |- | style="text-align:center;width:10%;" | '''[[1904]]''' | [[Professor|Honorarprofessor]] at the [[University of Berlin]], collaboration with [[Emil Fischer]] |- | style="text-align:center;width:10%;" | '''[[1907]]''' | [[Emeritus]]; starts his own private laboratory in [[Godesberg am Rhein]] |} '''Scientific contributions:''' * Described the [[condensation]] of [[aromatic]] [[aldehyde]]s with [[aliphatic]] aldehydes or [[ketone]]s in [[1881]]. Today, this reaction is commonly referred to as the [[Claisen-Schmidt condensation]]. * Discovered ([[1887]]) the condensation reaction of an [[ester]] with an activated [[methylene|methylene group]], now known as the [[Claisen condensation]]. * Synthesis of [[cinnamate]]s by reacting aromatic aldehydes with esters. The reaction is known as the [[Claisen reaction]] and was described by Claisen for the first time in [[1890]]. * Discovered the thermally induced [[rearrangement]] of [[allyl]] [[phenyl]] [[ether]] in [[1912]]. He details its reaction mechanism in his last scientific publication ([[1925]]). In his honor, the reaction has been named the [[Claisen rearrangement]]. * Synthesis of [[isatin]] via a process known as the [[Claisen isatin synthesis]], described for the first time in [[1879]]. * Designer of a special distillation flask, now known as the [[Claisen flask]]. ==See also== *[[Claisen condensation]] *[[Claisen flask]] *[[Claisen isatin synthesis]] *[[Claisen reaction]] *[[Claisen rearrangement]] *[[Claisen-Schmidt condensation]] ==References== *W Pötsch. Lexikon bedeutender Chemiker (VEB Bibliographisches Institut Leipzig, 1989) (ISBN 3323001850) {{DEFAULTSORT:Claisen, Rainer Ludwig}} [[Category:1851 births]] [[Category:1930 deaths]] [[Category:German chemists]] [[Category:University of Bonn alumni]] [[Category:University of Bonn faculty]] [[de:Ludwig Claisen]] [[fr:Ludwig Claisen]] [[it:Rainer Ludwig Claisen]] [[nl:Rainer Ludwig Claisen]] [[sk:Rainer Ludwig Claisen]]