Wolff. Ludwig

Ludwig Wolff (1857-19191 was born in N6ustQdt/H8rdt, Germs ny, and received his Ph.D. from the University of Strasbourg working with Rudolf Fittig. He was professor of chemistry at the University of Jena. 

Wolff, L. Justus Liebigs Ann. Chem. 1912, 394, 25. Johann Ludwig Wolff (1857-1919) obtained his doctorate in 1882 under Fittig at Strasbourg, where he later became an instructor. In 1891, Wolff joined the faculty of Jena, where he collaborated with Knorr for 27 years. 

A useful variant of the inline-forming reaction just discussed involves the treatment of a ketone or aldehyde with hydrazine, H2NNH2, in the presence of KOH. This reaction, discovered independently in 1911 by Ludwig Wolff in Germany and N. M. Kishner in Russia, is a valuable method for converting a ketone or aldehyde into an alkane, RjOO — RjCHj. The Wolff-Kislmer reaction was originally carried out at temperatures as high as 240°C, but a modification in which dimethyl sulfoxide is used as solvent allows the process to take place near room temperature. 

Fazio VW, Cohen Z, Fleshman JW, van Goor H, Bauer JJ, Wolff BG, Cor-man M, Beart RW, Jr., Wexner SD, Becker JM, Monson JR, Kaufman HS, Beck DE, Bailey HR, Ludwig KA, Stamos MJ, Darzi A, Bleday R, Dorazio R, Madoff RD, Smith LE, Gearhart S, Lillemoe K, Gohl J. Reduction in adhesive small-bowel obstruction by Seprafilm adhesion barrier after intestinal resection. Dis Colon Rectum 2006 49 1-11. 

It was back in 1902 when Ludwig Wolff (1875-1919), a professor of analytical chemistry at the University of Jena, discovered the thermal rearrangement of ethyl 2-diazo-3-oxobutyrate in water to produce ethane-1,1-dicarboxylic acid, a reaction that has since been named after him Although it is now over 100 years old, the Wolff rearrangement is still alive and well, with prominent applications in modern synthetic organic chemistry. The main applications of the... 

In the case of 2-diazo-1,3-diketone and 2-diazo-l,3-ketoester substrates I Scheme 3.51. the Wolff rearrangement produces a-oxo-ketenes, a reaction that Ludwig Wolff himself studied in his early work. The control of the relative migratory aptitude of the R and R groups is a crucial parameter for the synthetic utility of this approach and essentially depends on the nature of the R groups, the geometry of the diazo substrate, and the activation method employed (see Section 3.3). Similarly to other ketenes, a-oxo-ketenes readily react with a large array of... 

Ludwig Wolff (1857-1919) was bom in Neustadt in the Palatinate and was educated at the University of Wtirzburg and Munich Polytechnic. In 1891, he became Professor of Analytical Chemistry at Jena, where he worked with Ludwig Knorr. His name is associated with the Wolff-Kishner reaction (1911) and the Wolff rearrangement (1912). 

This transformation is called the Wolff-Kishner reduction, named after the German chemist Ludwig Wolff (University of Jena) and the Russian chemist N. M. Kishner (University of Moscow). This provides a two-step procedure for reducing a ketone to an alkane ... 

In fact, there are many such ways to convert a carbonyl into a methylene group, two of which are shown in Figure 14.47. The Clemmensen reduction, named for its discoverer E. C. Clemmensen (1876-1941), takes place under strongly acidic conditions, whereas the Wolff-Kishner reduction (Ludwig Wolff, 1857-1919 N. Kishner, 1867-1935) requires strong base. 

Professor Ludwig Wolff (1857-1919), University of Jena, Germany Professor N. M. Kishner (1867-1935), University of Moscow. 

Ludwig Wolff made the discovery that diazo ketones can be converted into derivatives of an acid in 1915. Wolff found, for example, that the treatment of (o-diazoacetophenone (PhCOCHN2) with ethanolic ammonia and a silver... 

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