The reaction of decaborane with trimethylamine–alane to give a mixed boron–aluminium hydride derivative

Abstract

Trimethylamine–alane, Me₃N,AIH₃, reacts with decaborane to give the trimethylammonium salt of a new anion (B₁₀H₁₂AIH₂^–),nEt₂O, where n= 1·5 to 2. This is the first example of 6,9 internally bridged derivative of B₁₀H₁₂^2– and contains direct Al–B bonds. Related reactions of decaborane with adducts of chloro- and alkyl-substituted alanes are also discussed. Controlled hydrolysis of the anion (B₁₀H₁₂AIH₂^–),nEt₂O, liberates only one molar equivalent of hydrogen, and salts of the anion B₁₀H₁₅^– were isolated from the hydrolysis mixture. The properties and structure of these compounds are considered.