Carbollide complex

Like many late transition metals, nickel has featured, albeit briefly, in the pursuit of poly(pyrazolyl)borate-metal-carbollide complexes. Thus, [c/oso-3-(r 2-Ph2Bp)-3,l,2-NiC2B9H11] (90 ) has been obtained as the tet-ramethylammonium salt,39 via the reaction of [Me4N][Ph2Bp] with the neutral bisphosphine nickel dicarbollide [doso-3,3-(PhEt2P)2-3,l,2-... 

The crystal structure of Sc carbollide complex is shown in Fig. 6.19. In the complex, each Sc is tj5 bonded to Cp, r 5 bonded to carbollide and to one-CH(SiMe3)2 group. The centers of the two tj5 groups form an angle of 137.8° with Sc and two of such units share a Li atom to the B atoms of each carbollide resulting in a dimeric anion with Li(THF)3 as the cation. 

The first thallium(I) n complexes with carbollide ligands were synthesized by Stone et al. (180) addition of an aqueous solution of thallium(I) acetate to an aqueous alkaline solution of the dicarbaundecaborane anion, 7,8-CzB, , or its C-alkyl derivatives causes the formation of the new compounds (LIVa-c) [Eq. (15)]. One of the thallium atoms in the air-stable,... 

Complexes with carbollide ligands have been prepared according to Eqs. (44) and (45) (232,246). These complexes are light yellow sublimable solids, monomeric in solution, in the gas phase, and presumably also in the solid state. Their stability is lower than that of the corresponding germanium and tin species. Their structures (see Fig. 15) have been deduced from spectroscopic data and by analogy with other metallacarborane species. 

Complexes containing monopentamethyl cyclopentadiene as oxo, alkyl and aryloxides, /S-diketones, hydrazine, dianionic carbollide derivatives have been characterized and are summarized below. 

Type A resembles the typical rf- coordination as it is known for many complexes of the dicarbollide ( /Wo-C2B9Hi3 ) and carbollide ligands and is... 

The dianionic carbollide ligand [C2B9Hn] prevents dimerization in alkyl or hydrlde-Cp Sc derivatives which as monomers are catalytically active in a-olefin polymerization (Shapiro et al. 1990). The crystal structure has been determined for the [Cp [(Me3Si)2CH]Sc(carbollide)]2Li (Li(THF)3) complex obtained by alkylation of Cp (C2B9Hii)Sc(THF)3 with LiCH(SiMc3)2 followed by pentane diffusion in toluene... 

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