Carboranyl

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. 

Reduction of the ditellurium derivatives with sodium borohydride in ethanol and reaction of the resulting sodium 9-carboranetellurolate with methyl iodide yielded 9-carboranyl methyl telluriums3,4 (s.p. 185). 

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 ditellurium compounds were treated with sodium borohydride and the tellurols reacted with methyl iodide to produce 9-carboranyl methyl tellurium derivatives1 (see p. 5). 

Sodium ortho- and we/a-9-carboranetellurolates3 are obtained by reduction of the bis[9-carboranyl] ditellurium derivatives with sodium borohydride in a 2 1 mixture of ethanol/benzene at 40°. 

The methylation of sodium 9-or//tocarboranetellurolate2,3 and 9-wietucarboranetelluro-late2 with methyl iodide yielded 9-carboranyl methyl tellurium compounds. 

The carboranyl alcohol can also be prepared from the stannyl carborane and an aldehyde using Pd2(dba)3-CHCl3/dppe. The carborane is stable to Brpnsted and Lewis acids and to LiAlH.. 

A final class of high burning rate proplnts combines the high density and high impulse difluoramino compds in their binders with the carborane derivatives. Jones (Ref 79) described the preparation of TVOPA (1,2,3-tris [1,2-bis-(difluoramino)ethoxy] propane, 1PCA (1-iso-propenyl-carboranyl-acetone) and NFPA (2,3-bis(difluoramino) propyl acrylate) and proplnts... 

Second, as a logical development of the first approach, polyphosphazenes have been synthesized that bear phosphine units connected to aryloxy side groups (37). The phosphine units bind organometallic compounds, such as those of iron, cobalt, osmium, or ruthenium (38). In several cases, the catalytic activity of the metal is retained in the macromolecular system (39). A similar binding of transition metals has been accomplished through nido carboranyl units linked to a polyphosphazene chain (40). 

DIRECT SYNTHESIS FROM N-SILYL-PHOSPHORAMINES CARBORANYL DERIVATIVES BIOACTIVE AND BIOERODABLE POLYMERS (STEROIDS, DOPAMINE, PROCAINE, ETC.)... 

Quite a number of silylnickel and silylenenickel compounds have been reported, and only a few can be cited here2305-2309 Bis(silyl)nickel complexes have been implicated as important intermediates in Ni-catalyzed double silylation of various organic substrates. Using an o-bis(dimethylsilyl)carborane ligand, complex (930) could be isolated and structurally characterized 2310 Its unusual thermal stability is attributed to the advantageous steric and electronic properties of the carboranyl unit. (930) undergoes... 

III. Metal Compounds Containing an X,Y-Carboranyl Chelating Ligand. 77... 

B. Metal Compounds Containing a C,N-Carboranyl Chelating Ligand. .. 80... 

METAL COMPOUNDS CONTAINING AN X.Y-CARBORANYL CHELATING LIGAND... 

---