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Zinc dust was then stirred in, reducing the oxime group to the amine. This reduction consumes two equivalents of zinc and four equivalents of acetic acid. Knorr 1886 synthesis. Modern practice is to add the oxime solution resulting from the nitrosation and the zinc dust gradually to a well-stirred solution of ethyl acetoacetate in glacial ...
The Reformatsky reaction (sometimes transliterated as Reformatskii reaction) is an organic reaction which condenses aldehydes or ketones with α-halo esters using metallic zinc to form β-hydroxy-esters: [1] [2] The Reformatsky reaction. The organozinc reagent, also called a 'Reformatsky enolate', is prepared by treating an alpha-halo ester ...
A modified condition, involving activated zinc dust in an anhydrous-solution of hydrogen chloride in diethyl ether or acetic anhydride, results in a more effective reduction. The modified Clemmensen reduction allows for the selective deoxygenation of ketones in molecules that contain stable groups such as cyano , amido , acetoxy , and carboalkoxy .
Raney nickel, platinum on carbon, or zinc dust and formic acid or ammonium formate [6] α,β-Unsaturated nitro compounds can be reduced to saturated amines by: Catalytic hydrogenation over palladium-on-carbon; Iron metal; Lithium aluminium hydride [27] (Note: Hydroxylamines and oximes are typical impurities.)
The Tipson–Cohen reaction is a name reaction first discovered by Stuart Tipson and Alex Cohen at the National Bureau of Standards in Washington D.C. [1] The Tipson–Cohen reaction occurs when two neighboring secondary sulfonyloxy groups in a sugar molecule are treated with zinc dust (Zn) and sodium iodide (NaI) in a refluxing solvent such as N,N-dimethylformamide (DMF) to give an ...
Increased use of galvanised steel has resulted in increased levels of zinc in steel scrap which in turn leads to higher levels of zinc in electric arc furnace flue dusts. As of 2000, the waelz process is considered to be a "best available technology" for flue dust zinc recovery and the process is used at industrial scale worldwide. [7]
Zinc oxide is used as a white pigment in paints. Roughly one quarter of all zinc output in the United States in 2009 was consumed in zinc compounds; [122] a variety of which are used industrially. Zinc oxide is widely used as a white pigment in paints and as a catalyst in the manufacture of rubber to disperse
The Simmons–Smith reagent is used to prepare cyclopropanes from olefin using methylene iodide as the methylene source. The reaction is effected with zinc. The key zinc-intermediate formed is a carbenoid (iodomethyl)zinc iodide which reacts with alkenes to afford the cyclopropanated product. The rate of forming the active zinc species is ...