Boron polyhedral

Boron Inorganic Chemistry Boron Metallacarbaboranes Boron-Nitrogen Compounds Boron Organoboranes Boron Polyhedral Carboranes. [Pg.416]

This article covers only a part of the chemistry of boron. Boron-carbon compounds are covered in other articles in this volume see Boron Organoboranes Boron Metallacarbaboranes, and Boron Polyhedral Carboranes). The main subject of the latter two articles, and the separate one on Boron Hydrides is the extensive chemistry of the multicenter bonded boron-hydride systems. This area has been a major focus of boron research for the past 60 years. There is some direct overlap between the two articles Borides Solid-state Chemistry and Borates Solid-state Chemistry, and this more general one covering the inorganic chemistry of boron. Boron-Nitrogen Compounds are also covered separately. These articles should be consulted for more detailed discussions of the structure, bonding, and properties of borides, solid-state borates, and boron-nitrogen compounds. [Pg.419]

Metallacarbaboranes (or metallacarboranes) are compounds that contain cluster polyhedra comprising carbon, boron, and metal atoms in various combinations. The first metallacarbaborane clusters were prepared by Hawthorne in 1965, and were derived from the icosahedral closo-carbaborane l,2-C2BioHi2 see Boron Polyhedral Carbo-ranes) by the replacement of one BH vertex with a metal center. Compounds such as [Fe(C2B9Hn)2]" (n = 1 or 2) can be represented as the commo-metallacarbaborane (1) or as... [Pg.443]

Boron Hydrides Boron Polyhedral Carboranes Electronic Stmctnre of Clusters. [Pg.462]

Boron Hydrides Boron Inorganic Chemistry Boron Organoboranes Boron Polyhedral Carboranes Cluster Compounds Inorganometalhc Compounds Containing Transition Metal Main Group Elements Electronic Structure of Main-group Compounds. [Pg.478]

Cyclic organoboranes containing mnltiple boron atoms within the ring stracture have been extensively stndied as precursors to (multidecker) transition-metal complexes and to nonclassical organoboranes (see Boron Metallacarbabo-ranes and Boron Polyhedral Carboranes). Earlier efforts have been thoroughly reviewed. Recently, a series of triboracyclopentane derivatives were reported by Bemdt and Schleyer (Scheme 6). " Reduction of these boracy-cles gave the nonclassical bishomoaromatic anions (28) and homoaromatic dianions (29). Related trishomoaromatic dianions obtained via reduction of 1,3,5-triboracyclohexane derivatives with lithium were studied by Siebert and Schleyer. i 5> ... [Pg.488]

Based in part on the article Boron Polyhedral Carhoranes by Robert E. Williams which appeared in the Encyclopedia of Inorganic Chemistry, First Edition. [Pg.520]

Alloys Aluminum Inorganic Chemistry Borides Solid-state Chemistry Boron Polyhedral Carboranes Carbon Fullerenes Gallium Inorganic Chemistry Polyhedra. [Pg.4004]

In discrete molecules, the elements of group 13 are most typically found in the +3 oxidation state. There are major exceptions to this rale, such as the polyhedral boranes (see Boron Hydrides) and carboranes (see Boron Polyhedral Carboranes and Boron Metallacarbaboranes), which formally contain and are outlined elsewhere in this Encyclopedia, and the compounds of thallium (Tl), which typically contain Tl for the reasons described above. Thus, in this section, compounds containing group 13 elements in the atypical -I-1 and -1-2 oxidation states are presented. [Pg.5835]

Boron Polyhedral Carboranes Group 14 Multiple Bonding Low Oxidation State Main Group Main Group Carbenes Main Group Multiple Bonding Periodic Table Trends in the Properties of the Elements Polyhedra Zintl Compounds. [Pg.5874]

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