Dicarbollide ions boron complexes

As a second illustrative aspect of the boron/carbon connection, we consider the dicarbollide ion, C2B9H112-, which can be pictured as derived from Bi2Hi22- by removing one BH(t) vertex and replacing two adjacent borons of the exposed pentagonal face by carbon atoms, as shown in Fig. 3.116. This ion exhibits remarkable electronic mimicry of the cyclopentadienyl ion (C5H5-, Section 3.3.2), forming similar coordination and sandwich complexes with many metallic species.162... 

The 6-phenyl-1,2-dicarbollide ion derived from 3-phenyl-1,2-dicarba-closododecaborane (12) by boron atom removal with base also forms a cobalt complex [l,2-B8H8B(C6H5)C2H2]2Co under the normal conditions (19). 

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