![]() With the air electrode such batteries are a variety of fuel cell. In one design approach, the metal anodes are contained in a pocket, which can be removed when the anode is exhausted and replaced with a fresh electrode, thus mechanically recharging the system. VII.C Mechanically Recharged Systems: Zinc/Air and Aluminum/AirĪ development effort has been carried out for many years with various zinc or aluminum anode/air-fed cathode systems. These would permit very large liquid reservoirs in a low-cost system where the parts are not transported. ![]() The Lewis Laboratories of the National Aeronautics and Space Administration have worked on redox couple systems with special ion exchange membrane electrodes. Each of the systems tested hits been handicapped by difficulties in the construction when temperature cycled and a disappointingly low energy density when the containment system was carefully designed. Notable examples include sodium/ antimony trichloride with aluminum chloride/sodium chloride electrolyte and lithium/iron sulfide cells. Methyl iodide oxidatively adds to ( 142) subsequent reductive elimination of methyl chloride from the intermediate ( 145) yields the iodostibine ( 146) in quantitative yield (Equation (17)) 〈89TL4841〉.īrooke Schumm Jr., in Encyclopedia of Physical Science and Technology (Third Edition), 2003 VII Other Storage Batteries and Mechanical Recharging VII.A High-Temperature BatteriesĪ number of systems with sodium or lithium anodes and various cathodes have been tested and developed to various degrees. The addition of benzyltrimethylammonium chloride to ( 144 X = Cl) converted it back into the neutral compound ( 143 X = Cl). The most reasonable structure for ( 143 X = I) was determined to be the ionic formulation ( 144 X = I). The structure was assigned to the compounds ( 143) on the basis of 1H NMR spectroscopy. Treatment of ( 143 X = Cl) with KF in DMF gave the difluoro compound ( 143 X = F). Halogenation of ( 142) yielded the corresponding dihalides ( 143 X = Cl, Br or I) and the reaction of ( 143 X = Cl or Br) with SbCl 5 or AgBF 4 resulted in the formation of compounds with Sb N bonds ( 144 X = Cl or Br) (Equation (16)). The one-pot reaction between di(2-bromobenzyl)methylamine ( 141), n -butyllithium, and antimony trichloride, followed by p-tolyllithium, afforded ( 142) in 23% yield 〈88TL5401〉. Similarly, primary stibine 89b is obtained in 51% yield from the corresponding bromostibine 81b by treatment with LAH in tetraglyme ( Scheme 27). The mixed compound bis(trimethylsilyl)methylstibino chloride (TMS) 2CH(H)SbCl is postulated to be an intermediate in the formation of 90 via reaction of (TMS) 2CHSbCl 2 with LAH and loss of H 2. Distibine 90 is formed in 93% yield from the same reagents as 89a but in a “reverse addition” reaction. By contrast, stibine 89a is stable at room temperature in a sealed tube for weeks, and at −28 ☌ it is stable indefinitely. However, many of them, such as RSbH 2 (R = Me, Ph) and R 2SbH (R = Me, Et), decompose in minutes or hours at room temperature. It can be noted that hydrides of main group 15 elements are important compounds, frequently used as reducing agents or precursors for electronic materials. Thus, addition of dichlorostibine 82 in Et 2O to LAH at −60 ☌ affords the primary stibine 89a in 69% yield. The preparation of stable primary and secondary stibines has been reported. * Undecaamminetetraruthenium dodecaoxide, 4593 * Bis(1-chloroethylthallium chloride) oxide, 1586 An additional method involves reaction of Me 4SbI in EtOH with I 2 in benzene. However, Me 4SbI 3 is made from addition of I 2 to (Me 4Sb) 3I 8 in a reversible reaction. The reaction of I 2 with Me 4AsI, Me 3SbI, Me 2Et 2SbI, MeEt 3SbI, or Et 4SbI in the absence of solvent produces the respective arsonium/stibonium triiodide. 2.09.3.1.6 Miscellaneous methods for alkylarsine halides The cleavage of (CF 3) 2AsAsMe 2 can be accomplished with Mn(CO) 5I forming (CO) 5MnAs(CF 3) 2 and Me 2AsI, which will react with the starting compound. 2.09.3.1.5 Cleavage of As As, Sb Sb, and Bi Bi bonds 2.09.3.1.4 Reactions involving cleavage of As, Sb, and Bi C bondsĪ study on homolytic versus heterolytic bond cleavage was published in 1999 complete with ab initio MO calculations on C As, C As, and C As bonds. No further advances have occurred in this area since the publication of COFGT (1995). ![]() 2.09.3.1.2 Pyrolysis of R 3EX 2 and R 2EX 3 (E = As, Sb)Īonuma and co-workers observed that the step-wise pyrolysis of Me 3SbI 2 produced Me 2SbI and MeSbI 2 as mixtures. ![]()
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