Nine-Vertex Metallocarboranes

The first metallocarborane of this geometry to be synthesized was an unexpected product. In an attempt to prepare a ten-vertex manganese carbonyl complex, the C2B7Hii2 ion, discussed in Section VII, was reacted with BrMn(CO)5. Surprisingly, the only metal-containing compound isolated from the reaction mixture had just 6 boron atoms (36, 50). The course of the reaction may be outlined as follows  

Similar results were observed when ClMn(CO)5 or Mn2(CO)io were used as metal sources and when C-phenyl- or C, C -dimethyl-substituted car-boranes were used as starting materials. The structure proposed for this complex and later confirmed by a crystallographic study (63) was based 

Commo complexes containing two fused nine-vertex polyhedra may be prepared by the polyhedral expansion of 1,7-C2B6H8 with CoCl2 in the 

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Ten-vertex metallocarboranes containing both cobalt and nickel in the same polyhedron have been synthesized from the nine-vertex anionic species C5H5C0CB7HS- (Section VIII) by polyhedral expansion (87). The resulting neutral complexes, of formula (C5Hs)2CoNiCB7H8 and con-... 

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