C2B3 Ring Triple-decker Sandwiches

Methods for introducing functional groups into Co(C2B3)M triple-deckers, important in many synthetic strategies for constructing multicage oligomers and polymers (Section 3.01.4.5), have been developed with the synthesis of 

B-alkynyl and B-halo derivatives. Hydridometal triple-deckers have also been synthesized. Carborane- 

Triple-decker sandwiches that are capped at one or both ends by C2B3 rings are important synthons for the construction of larger stacks via coordination to metal ions (see the following subsection), and many of these have been synthesized and their reactivity investigated.75,78 Bent triple-deckers such as 6879,80 that resemble bent metallocene complexes have been prepared, structurally characterized, and shown to be amenable to the introduction of halo- and organosubsitutuents at boron.80 

Triple-decker sandwiches of type 69 containing central metal-metal linkages have been synthesized.76 

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