Metallaborane reactivity

Just as for group 5, 6, and 7 ( -CsF MCU species, Fehlner has shown that BH3-THF or Li[BH4] react with group 8 and 9 cyclopentadienyl metal halides to result in metallaborane clusters, many of them having a metal boron ratio of 1 3 and 1 4, and much of the synthetic chemistry and reactivity shows close connections with the earlier transition metals. The main difference between the early and later transition metallaboranes that result is that the latter are generally electron precise cluster species, while as has been shown, the former often adopt condensed structures. Indeed, as has been pointed out by King, many of the later transition metallaborane clusters that result from these syntheses have structures closely related to binary boranes and, in some cases, metal carbonyl clusters such as H2Os6(CO)18.159... 

C.E. Housecroft (1994) Boranes and Metallaboranes Structure, Bonding and Reactivity, 2nd edn, Ellis Horwood, Hemel Hempstead - Chapter 2 includes an account of the interpretation of B and H NMR spectra of boranes and their derivatives. 

B. G. Cooksey, J. D. Gorham, and J. H. Morris, J.C.S. Dalton, 1978, 141. Electrolysis of Borane anions at reactive metal anodes A convenient route to metallaboranes. 

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