13771-22-7Relevant academic research and scientific papers
Metal tetrahydridoborates and (tetrahydroborato)metalates. 10. NMR study of the systems AlH3/BH3/THF and LiAlH4/BH3/THF
N?th, Heinrich,Rurl?nder, Robert
, p. 1062 - 1072 (2008/10/08)
The systems AlH3/BH3/THF and LiAlH4/BH3/THF have been investigated by means of 11B and 27Al NMR spectroscopy. The NMR spectra indicate equilibria of the types AlH3 + nBH3 ? AlH3-n(BH4)n and 2AlH3-n(BH4)n ? AlH3-(n+1)(BH4)n+1 + AlH3-(n-1)(BH4)n-1 with all Al species and BH3 coordinated with THF. An even more complex situation holds for the LiAlH4/BH3/THF system. The species formed are LiBH4 and AlH3-n(BH4)n in equilibrium with LiAlH3-n(BH4)n+1. The equilibria are shifted toward the (tetrahydroborato)aluminates more strongly with increasing n and decreasing temperatures. At higher temperatures a rapid BH4- exchange prevails. Moreover, at high n values it is not only THF that competes with Al-H for BH3 but also BH4- which gives rise to B2H7-.
