Silver and Copper Complexes with closo-Polyhedral Borane, Carborane and Metallacarborane Anions: Synthesis and X-ray Structure

Synthesis and structure of silver and copper salts and complexes with polyhedral boron hydride anions, including closo-decaborate [B10H10](2-), closo-dodecaborate [B12H12](2-), 1-carba-closo-decaborate [1-CB9H10](-), carba-closo-dodecaborate [CB11H12](-), and cobalt bis(dicarbollide)[3,3'-Co(1,2-C2B9H11)(2)](-) anions and their derivatives, are reviewed. The complexes demonstrate a wide variety of structural types, relating to both the metal coordination environment and coordination modes of boron hydride anions. The latter can range from strong coordination via the polyhedron triangular face including formation of 3c-2e MHB bonds in the case of the [B10H10](2-) dianion, the structure of which contains two four-coordinated boron atoms, to very weak M center dot center dot center dot H interactions with the hydride atoms in the case of bulky [3,3'-Co(1,2-C2B9H11)(2)](-) monoanion.