Magnesium-reduction reaction

In the Boulder City plant, the magnesium reduction reaction is carried out in a mild steel cylindrical vessel about 3 ft deep by 30 in. diameter, fitted with a tall neck containing two inlet pipes. The lid and neck comprise a single piece which is attached to the cylindrical base by means of a weld, the weld being made for each run and ground away to open the vessel. A tapping hole is provided at the base of the reactor. The reactor is heated in... 

The most well-known method of titanium production is the Kroll process, which involves the reduction of TiCl4 by magnesium. The first step in the process is the preparation of the tetrachloride itself, which is carried out by the chlorination of a mixture of carbon with rutile or il-menite. The Kroll magnesium-reduction reaction takes place in a closed heated reactor vessel under an inert atmosphere. Liquid TiCU is introduced to the liquid magnesium already present in the vessel, thereby initiating the reaction 2Mg + nCl4 —> 2MgCl2 + Ti. The reaction prod-... 

The manufacture of refractory metals such as titanium, zirconium, and hafnium by sodium reduction of their haHdes is a growing appHcation, except for titanium, which is produced principally via magnesium reduction (109—114). Typical overall haHde reactions are... 

Reduction. BrezeHus attempted the first reduction of zirconium in 1824 by the reaction of sodium with potassium fiuorozirconate. However, the first pure ductile metal was made in 1925 by the iodide thermal-dissociation method. The successfiil commercial production of pure ductile zirconium via the magnesium reduction of zirconium tetrachloride vapor in an inert gas atmosphere was the result of the intense research efforts of KroU and... 

Reduction reactions are perhaps the second most common type of potentially hazardous reactions. Materials such as metallic sodium, aluminium, and magnesium hydrazine diborane sodium hydride and hydrogen have all been involved in a wide variety of chemical accidents. 

Fluorides are nonhygroscopic, and their melting points are higher than those of the corresponding chlorides. Besides, the fluoride reduction reactions are considerably more exothermic. The prime examples of the use of fluorides as intermediates are the reduction of uranium tetrafluoride by calcium or magnesium the reduction of rare earth fluorides by calcium, reduction of beryllium fluoride by magnesium and the reduction of potassium tantalum double fluoride by sodium. 

However, the reduction reactions in which a solid reducing agent is used usually give impure products. In this case, the product contains 80% to 95% boron that also contains magnesium and boron oxide as impurities. The boron produced in this way is a brownish-black form having a density of 2.37 g/cm3. 

Two important reduction reactions of magnesium that are of commercial interest are the production of titanium by Kroll process and obtaining uranium from its fluoride ... 

Many metals are also vulnerable to acids, undergoing an oxidation /reduction reaction that produces the metal ion and hydrogen gas. The balanced equation for the reaction between HCl and magnesium is... 

The reaction of magnesium and oxygen is an example of an oxidation reaction. The combination of an element with oxygen was the traditional way to define an oxidation reaction. This definition of oxidation has been broadened by chemists to include reactions that do not involve oxygen. Our modern definition for oxidation is that oxidation takes place when a substance loses electrons. Anytime oxidation takes place and a substance loses one or more electrons, another substance must gain the electron(s). When a substance gains one or more electrons, the process is known as reduction. Reactions that involve the transfer of one or more electrons always involve both oxidation and reduction. These reactions are known as oxidation-reduction or redox reactions. 

Nitroolefins are excellent Michael acceptors which react with a broad range of nucleophiles in a Michael fashion. The resulting functionalized nitroalkanes can be readily converted into amines by reduction reactions or to carbonyl compounds by a Nef reaction . The addition of nucleophiles to nitroolefins is complicated by the subsequent addition of the resulting nitronate to remaining nitroolefin. Whereas such a side-reaction is quite fast for lithium and magnesium nitronates. it is slow for zinc... 

Magnesium metal burns in air with an intense white light to form solid magnesium oxide. Red phosphorus reacts with liquid bromine to form liquid phosphorus tribromide. Purple aqueous permanganate ion, MnC>4-, reacts with aqueous Fe2+ ion to yield Fe3+ and pale pink Mn2+. Although these and many thousands of other reactions appear unrelated, all are oxidation-reduction reactions. 

An equilibrium involving substituent exchange between magnesium dialkyls and magnesium dialkoxides recently has been postulated in order to explain stereoselectivity of certain Grignard reduction reactions (64). 

Zizaene sesquiterpenes were the subject of considerable synthetic interest in the 1970s and several synthetic strategies to construct the tricyclo[6.2.1.0 ]undecane skeleton involved an intramolecular diazoalkane-carbonyl ring expansion, an intramolecular magnesium-ene reaction, and a titanium-promoted reductive coupling. - ... 

The triplet states of porphyrins undergo oxidation and reduction reactions. Zinc and magnesium tetraphenylporphyrin in their triplet states are oxidised... 

Phospholyl anions are also isoelectronic to Cp ligands, and these species readily complex Zr. A reduction reaction of (C4Me4P)2ZrCl2 by magnesium in THF gives transient diphosphazirconocene species which can be trapped by CO, bis trimethylsilyl acetylene, or 2-butyne to yield the corresponding dicarbonyl (67), zirconacyclopropene (68), and zirconacyclopentadiene (69). ... 

Pandit has provided evidence for the Lewis acid catalysis postulated to operate in these reduction reactions. The reduction of various cinnamoylpyridines by 1,4-dihydropyridine derivatives to the corresponding saturated ketones is catalyzed by zinc or magnesium cations. The reduction rate was fastest in the case of 2-cinnamoylpyridine, in which the metal ion can complex simultaneously to both the nitrogen and oxygen sites (Scheme 78). This example is regarded as a model of Lewis acid catalysis of the NADH-dependent enzymatic reduction of A -3-keto steroids. 

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