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Wurtz Coupling
In organic chemistry, the Wurtz reaction, named after Charles Adolphe Wurtz, is a coupling reaction whereby two alkyl halides are treated with sodium metal to form a higher alkane. : 2 R−X + 2 Na → R−R + 2 NaX The reaction is of little value except for intramolecular versions. A related reaction, which combines alkyl halides with aryl halides is called the Wurtz–Fittig reaction. Mechanism The reaction proceeds by an initial metal–halogen exchange, which involves this idealized stoichiometry: : R−X + 2 M → RM + MX This step involves the intermediacy of radical species R·. This step resembles the formation of a Grignard reagent. These RM intermediates have been isolated in several cases. The organometallic intermediate next reacts with the alkyl halide forming a new carbon–carbon covalent bond. : RM + RX → R−R + MX The process resembles an SN2 reaction, but the process is probably complex, which may explain the inefficiency of the reaction. Exam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Adolphe Wurtz
Charles Adolphe Wurtz (; 26 November 181710 May 1884) was an Alsatian French chemist. He is best remembered for his decades-long advocacy for the atomic theory and for ideas about the structures of chemical compounds, against the skeptical opinions of chemists such as Marcellin Berthelot and Henri Étienne Sainte-Claire Deville. He is well known by organic chemists for the Wurtz reaction, to form carbon-carbon bonds by reacting alkyl halides with sodium, and for his discoveries of ethylamine, ethylene glycol, and the aldol reaction. Wurtz was also an influential writer and educator. Life Adolphe Wurtz (he never used the name "Charles") was born in Strasbourg, where his father, Johann Jacob (Jean Jacques) Wurtz, was a Lutheran pastor in the nearby town of Wolfisheim. His wife, Adolphe's mother, Sophie Kreiss, died in 1878. When he left the Protestant gymnasium at Strasbourg in 1834, his father allowed him to study medicine as next best to theology. He devoted himself s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese
Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy uses, particularly in stainless steels. It improves strength, workability, and resistance to wear. Manganese oxide is used as an oxidising agent; as a rubber additive; and in glass making, fertilisers, and ceramics. Manganese sulfate can be used as a fungicide. Manganese is also an essential human dietary element, important in macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. It is found mostly in the bones, but also the liver, kidneys, and brain. In the human brain, the manganese is bound to manganese metalloproteins, most notably glutamine synthetase in astrocytes. Manganese was first isolated in 1774. It is familiar in the laboratory in the form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
