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Zinc is a strong reducing agent with a standard redox potential of −0.76 V. Pure zinc tarnishes rapidly in air, rapidly forming a passive layer. The composition of this layer can be complex, but one constituent is probably basic zinc carbonate, Zn 5 (OH) 6 CO 3. [8] The reaction of zinc with water is slowed by this passive layer.
The first reaction is the formation of the N-2,4-dinitrophenyl-pyridinium salt (2). This salt is typically isolated and purified by recrystallization. The formation of the DNP-pyridinium salt. Upon heating a primary amine with the N-2,4-dinitrophenyl-pyridinium salt (2), the addition
Related to the preparation of Lucas' reagent, tetrachlorozincates are often generated by combining hydrochloric acid and zinc chloride. A related anion is [Zn 2 Cl 6] 2−, in which again Zn(II) adopts a tetrahedral geometry. [2] Portion of the crystal structure of the salt hexaacetonitrilenickel(II) tetrachlorozincate ([Ni(CH 3 CN) 6] 2+ [ZnCl ...
The reaction is named after Ei-ichi Negishi who was a co-recipient of the 2010 Nobel Prize in Chemistry for the discovery and development of this reaction. Negishi and coworkers originally investigated the cross-coupling of organoaluminum reagents in 1976 initially employing Ni and Pd as the transition metal catalysts, but noted that Ni ...
The reaction is named after its co-discoverer, John E. McMurry. The McMurry reaction originally involved the use of a mixture TiCl 3 and LiAlH 4, which produces the active reagents. Related species have been developed involving the combination of TiCl 3 or TiCl 4 with various other reducing agents, including potassium, zinc, and magnesium.
Sodium zincate refers to anionic zinc oxides or hydroxides, depending on conditions. In the applications of these materials, the exact formula is not necessarily important and it is likely that aqueous zincate solutions consist of mixtures.
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 increased via ultrasonication since the initial reaction occurs at the surface of the metal.
Zinc has an electron configuration of [Ar]3d 10 4s 2 and is a member of the group 12 of the periodic table. It is a moderately reactive metal and strong reducing agent. [48] The surface of the pure metal tarnishes quickly, eventually forming a protective passivating layer of the basic zinc carbonate, Zn 5 (OH) 6 (CO 3) 2, by reaction with ...