Boron-Hydrogen Compounds

Boron-Hydrogen Compounds. Several studies of fluxional behaviour have been reported, and there has been a very authoritative discussion of intra molecular 

Boron-Hydrogen Compounds. Electrophilic iodination of gives an almost 

—Boron-Hydrogen Compounds. Theoretical calculations have been made of likely sites for electrophilic and nucleophilic attack in a number of boranes and related anions. Electrophilic benzoylation of PioHjo to form [2-BioH,COPh] follows simple second-order kinetics in acetonitrile. Reaction is inhibited by acid, and a kinetic analysis suggests that it is due to conversion of [BjoHioP into the unreactive conjugate acid with K = 4.6moldm. The reaction of 

The thermal rearrangement of 9,12-dichloro-CC -dimethyl-o-carbaborane yields 5,12-dichloro-CC -dimethyl-m-carbaborane as a major product, probably by a 

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Elemental boron and the borates are not considered to be toxic, and they do not require special care in handling. However, some of the more exotic boron hydrogen compounds are definitely toxic and do require care. 

This was one of the great shocks of my life and was the way we discovered that sodium borohydride possesses a remarkable stability (for a simple boron-hydrogen compound) in water. 

Cmelins Handhuch der Anorganischen Chemie, 8th Edn., Boron Compounds, Part 18, Boron Hydrogen Compounds, 1978 Springer Publ. Heidelberg. 

With this repertoire of bonding possibilities at our disposal, we car construct the molecular structures of various boron-hydrogen compounds, both neutral species and anions. The simplest is the tetrahydroborate126 or borohydride ion, BH. Although borane is unstable with respect to dimerization, the addition of a Lewis base, H , satisfies the fourth valency of boron and provides a stable entity. Other Lewis bases can coordinate as well. 

Rather than continue to progress from less complex to more complex boron-hydrogen compounds, it will be more convenient to jump to a complex but highly symmetric borohydride ion. lB,H 2f. It may be synthesized bv the pyrolvsis of the BjHJ ion ... 

A simple boron hydrogen compound BH3, does not exist. The electropositivity is too small for a salt-like boride B3+H3, while a sextet configuration would be produced with electron pair bonds. An octet configuration is indeed possible for BH4 in fact the salts Li[BH4] and Na[BH4] exist they have lattice structures similar to NaCl. The well-known LiAlH4, lithium-aluminohydride is also very similar. 

Supplement to Mellor s Comprehensive Treatise on Inorganic and Theoretical Chemistry, Vol. V, Boron. Part BI Boron-Hydrogen Compounds. Longman, London, 1981. 

Schlesinger and Burg describe many metallo borohydridcs which are metal-boron-hydrogen compounds containing unusually large amounts of hydrogen, prepared by the action of diborane on the metal alltyl compounds. 

The apparently bewildering variety of structures adopted by boron-hydrogen compounds (boranes) can be rationalized by recognizing some major families, illustrated by the series in Figure. 2. 

Boranes and borane ions are boron-hydrogen compounds that can also act as ligands. Carboranes are boranes in which some boron is replaced by carbon. Borane... 

Borverbindungen 14 Boron-Hydrogen Compounds, Part 1. Literature coverage from 1950 to the end of 1975. 

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