Ten-vertex monocarbaborane chemistry. Synthesis of carbon-substituted ligand derivatives 1-L-closo-1-CB9H9 and crystal and molecular structure of 1-(Me3N)-closo-1-CB9H9

Abstract

The monocarbaborane ligand derivative (1-(H₃N)-closo-1-CB₉H₉ has been isolated in 75% yield from the reaction between 6-(H₃N)-nido-6-CB₉H₁₁ and Et₃N·BH₃ in tetrahydrofuran in the presence of NaBH₄. Further reactions involving the exoskeletal H₃N group have led to the isolation of the series of related derivatives 1-L-closo-1-CB₉H₉, where L = Me₂S, [H₂N]^–, Me₃NH, or Me₃N. Boron-11 and ¹H NMR measurements were consistent with the proposed structure of all the compounds, with the structure of the NMe₃ derivative 1-(Me₃N)-closo-1-CB₉H₉ additionally determined by an X-ray diffraction analysis.