Carboranes sodium derivatives

The condensation of o- or w-carborane with tellurium tetrachloride in refluxing dichloromethane in the presence of aluminum trichloride produced 9-carboranyl tellurium trichlorides3 4. To facilitate the isolation of the tellurium compounds, the crude product was reduced with sodium sulfide in ethanol to the bis[9-carboranyl] ditellurium derivatives that were obtained as dark-red, air-stable crystals. 

Interaction ofocarborane or m-carborane with tellurium tetrachloride in dichloromethane in the presence of aluminum trichloride formed the 9-carboranyl tellurium trichlorides. These compounds were not isolated but reduced by sodium sulfide in aqueous ethanol to the corresponding dicarboranyl ditellurium derivatives, which in turn were reacted with thionyl chloride in ethanol or bromine in dichloromethane to give 9-carboranyl tellurium trihalidcs2 (see p. 5). 

The -CH2OH substituents present on the p-carborane reactant provide some solubility of the carborane derivative and are removed in situ by conversion to -COOH groups and subsequent decarboxylation. The properties of the [Bi2(OH)i2]2 ion are of particular interest since this structure offers a number of possible routes to dendritic organic and inorganic derivatives. An unexpected property is the facile aggregation of the disodium salt which has very limited water solubility. Sodium ions appear to coordinate with the -OH surface and provide intercage bonding. The dicesium salt is freely soluble in... 

Deamination of C-(trialkylamine)carbaundecaborane(12) derivatives to the carborane anion BjoHiaCH" can be accomplished with sodium metal or sodium hydride in tetrahydrofuran solution. A procedure using sodium metal is described here to illustrate this general reaction. The properties of the cesium and tetramethylammonium salts of the BioHi2CH anion are given. 

TRIMETHYLSILYL-SUBSTITUTED DERIVATIVES OF 2,3-DICARBA-mCARBORANE DIANION 2,3-BIS(TRIMETHYLSILYL)-2,3-DICARBA-mrfo-HEXABORATE(2 - )... 

Dodecahydro-do50-dodecaborate anion [B,2H,2] , the isoelectronic and isostructural analog of carboranes, is a typical representative of anionic polyhedral boron hydrides. Sodium salts of the parent cZo o-dodecaborate and their derivatives have a good solubility in water, which is an important precondition of many medical applications. The sodium salt Na2[Bj2Hj2] was found to be practically nontoxic with the approximate lethal dose for rats >7.5 g/kg of body weight, which is roughly comparable with that of sodium chloride [12], However, functionalization of this purely inorganic system till recently was problematic due to the absence of a clear reaction center. There are two... 

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