Cluster compounds Hypho

Derivatives of the trishomotriborirane dianion P are formed when alkali metals react in donor solvents with 1,3,5-triboracyclohexane derivatives. The dianion [(CHMe)3(MeB)3]2 has 20 SE and according to the cluster rules classifies as 2,4,6-tricarba-hypho-hexaborane-diid. However, the compounds exist as contact ion pairs, and are therefore regarded as heterocarboranes (see Section 3.2.8). 

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