Issue in Honor of Prof. Dr. Manfred Schlosser
ARKIVOC 2015 (iv) 1-8
particular. His research studies in fields such as organophosphorus, organofluorine and organometallic chemistry combined both novel mechanistic insight and synthetic applications. He contributed to ca. 400 publications and gave about 300 plenary lectures. His concepts and findings are summarized in several review articles. He was editor of several books on organometallic chemistry, and the third edition of a very famous one was recently published (Organometallics in Synthesis: A Manual, Wiley, Chichester, 2013).
Figure 5. Manfred in his office, Lausanne (September 2010). Among the many contributions of Manfred Schlosser to organic chemistry we wish to cite his stereoselective olefination procedures (“Schlosser modifications of the Wittig reaction”), developed in Heidelberg,1,2 the copper-catalyzed alkylation of organomagnesium compounds (“Fouquet-Schlosser coupling”),3 the development and use of mixed-metal bases such as the LICKOR superbase,4,5 and intense efforts to rationalize substituent effects on the behaviour of substrates in reactions.6 Manfred Schlosser made a remarkable contribution to improve the stereoselectivity of the Wittig reaction1 with the development of the so-called “Schlosser Modification of the Wittig Reaction”. The latter has been used broadly in organic synthesis for the stereoselective formation of alkenes with non-stabilized ylides, allowing the E-configured olefins to be prepared in more than 99% purity, which makes it one of the most stereoselective reactions reported in literature.2,7 By introducing different electrophiles to the α-deprotonation intermediate (Schlosser termed it “betaine ylide”), Manfred Schlosser and E. J. Corey, independently, developed a new approach to trisubstituted ethylenic compounds (the so-called “SCOOPY reaction” or “three-dimensional Wittig reaction”).8 In addition, Manfred Schlosser contributed significantly to the mechanistic studies of Wittig and related reactions. He reported a series of elegant experiments aimed at trapping the betaine intermediates by incubating β-hydroxy phosphonium salts with acid at low temperature, and nicely explained the pronounced effect of lithium salts on the stereochemistry of Wittig reactions.1,9 Page 4
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