Aluminum chemistry

One of the more important recent developments in organometallic aluminum chemistry has been the formation and isolation of low-coordinate compounds, and, in particular, cations. These were first prepared in reactions of various aluminum reagents with crown ethers to form the inclusion compounds known as liquid clathrates. 71,72 Most of the evidence supports the presence of ion pairs as the basis of the solvent inclusion effect. Indeed, the compound [AlMe2-18-crown-6]+[AlMe2Cl2] was isolated from one such system (the cation is shown in Figure 6(a)).73 This was the first time the Me2Al+ unit had been structurally characterized. 

Wehmschulte, R. J. Power, P. P. Primary alanes and alanates useful synthetic reagents in aluminum chemistry. Polyhedron 2000, 19, 1649-1661. 

Science in its youth is always exciting to pursue. When I began my career forty years ago, aluminum chemistry was a newly emerging field. Thus, whatever I found was new and exciting. I am sure that every young researcher who is interested in bismuth chemistry will enjoy the still-unfolding era of this element prior to its full blooming - and I am also confident this book will provide a reliable compass for his or her journey of discovery. 

Coordination chemistry of aluminum prior to 1970 was included in Wade and Banister s account of the element.1 There are thorough reviews of aluminum chemistry with particular reference to oxygen compounds, halides and their adducts, which cover the period prior to... 

Easthouse KB, Spyridakis DE, Welch EB. 1993. Aluminum chemistry in two pristine alpine lakes of the central Cascades, Washington. Water Air Soil Pollut 71 377-390. 

Hemenway DR, Fitzgerald B. 1984. Characterization of aluminum chemistry for acid precipitation. Burlington, Vermont University of Vermont, Vermont Water Resources Research Center. Project Number G873-05. NTISNo. PB85-214542. 

Litaor MI. 1987. Aluminum chemistry Fractionation, speciation, and mineral equilibria of soil interstitial waters of an alpine watershed, Front Range, Colorado. Geochim Cosmochim Acta 51 1285-1295. 

Shultz AM, Begemann MH, Schmidt DA, et al. 1993. Longitudinal trends in pH and aluminum chemistry of the Coxing Kill, Ulster County, New York. Water Air Soil Pollut 69 113-125. 

Aside from its color, trivalent chromium differs most markedly from Al(III) in its complexing ability. There are no analogs in aluminum chemistry for many of the octahedral complexes formed by Cr(III) with CN, SCN, NOj, NH3, and with a number of organic amines. The octahedral complexes of aluminum are confined to those having Al—0 or Al—F bonds. In contrasting the complexes derived from the two... 

A.W. Apblett, Inorganic Aluminum Chemistry in Encyclopedia of Inorganic Chemistry, In R.B. King, R.L. Wells (Eds.), Wiley, Chichester, England, 1994, pp. 103-116. 

With these six chapters this volume will provide the scientific researcher and non-specialist alike with a complete and up-to-date coverage of biological aluminum chemistry. The volume can also be used as a starting point to begin more detailed studies in this area. All of the relevant literature can be found in these chapters. Finally, we have to mention that we are chemists and therefore we have not evaluated completely the medical and toxicological implications of the chapters. 

The electrolysis process for producing aluminum was developed by Charles Martin Hall while he was a student at Oberlin College. His work in aluminum chemistry eventually led to the formation of the Aluminum Company of America (ALCOA). The reduction process for aluminum can be represented as... 

McAvoy, D. C. 1988. Seasonal trends of aluminum chemistry in a second-order Massachusetts stream. J. Environ. Qual. 174 528-534. 

Rustad, L. E. Cronan, C. S. (1995). Biogeochemical controls on aluminum chemistry in the O horizon of a red spruce Picea rubens Sarg.) stand in central Maine, USA. 

Lydersen E., Salbu B., Poleo A. B. S., and Muniz I. P. (1990) The influence of temperature on aqueous aluminum chemistry. Water Air Soil Pollut. 51, 203—215. 

Similar bridging hydrogen atoms occur in many other boranes, as well as in carboranes, which contain both boron and carbon atoms arranged in clusters. In addition, bridging hydrogens and alkyl groups are frequently encountered in aluminum chemistry. A few examples of these compounds are shown in Figure 8-15. 

Synthetically more readily availability of aluminum chemistry in pericyclic reaction was made possible, in particular, by Yamamoto and coworkers, who showed that the steric bulk of aluminum reagents is synthetically strategic, facilitating unprecedented selectivity and reactivity. 

Figure 5.15. Solubility and speciation of Al in soil solution at several elevations of the Hubbard Brook Forest. (Adapted from C. T. Driscoll et al. 1985, Aluminum chemistry in a forested spodosoL Soil Sci. Soc. Am. I. 49 437-444.)...

The aluminum present in ionic form in natural water can normally be expected to occur for the most part as complexes of fluoride or hydroxide, or of sulfate in some waters of low pH. These are possibly overshadowed in waters whose pH is below neutrality by polymerized hydroxide aggregates of colloidal or subcolloidal size. The occurrence of polymerized hydroxide will depend on the past history of the water and on kinetic rather than equilibrium considerations. Some standard procedures for determination of aluminum are insensitive to the hydroxide polymer and many existing analyses probably reflect this fact. The behavior of aluminum in natural water is probably also related to concentrations of dissolved silica. This aspect of aluminum chemistry is being studied in our laboratory. 

Many workers have tended to restrict their interpretations to thermodynamic approaches. The application of thermodynamics to aqueous aluminum chemistry, however, may be restricted as follows (a) In many cases, a true equilibrium state may not have been reached, yet the rate of equilibration is too slow to be detected under ordinary laboratory conditions. (b) The position of equilibrium and/or the rate of equilibration may vary with the nature and concentration of the counter anions present, yet in most studies of aluminum hydrolysis the role of counter anions has not been considered. Therefore, the conclusion derived under one condition is not necessarily valid under another condition in which diflFerent counter anions are present. A failure to recognize these possible... 

Many of the older studies have been reviewed in classic works, such as the monograph by Coates (8), the treatise by Mole and Jeffery (35) on aluminum chemistry, and that on reaction mechanisms by Matteson (ii). 

Nietfeld, H.W.F., 2000. Modeling the dynamics of the rhizosphere aluminum chemistry in acid forest soils. In Gobran, G.R., Wenzel, W.W., Lombi, E (Eds.), Trace Elements in the Rhizosphere. CRC Press, Boca Raton, FL, pp. 253-307. 

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