Synthesis and characterisation of the halogenated azanonaboranes [(iPrNH2)B8H10XNHiPr] (X=Cl, Br, I) and their unexpected hydrolysis to hypho-[B5H10(μ-NHiPr)]

Treatment of [(iPrNH2)B8H11NHiPr] with elemental halogen affords the 8-exo-halogen-substituted derivatives [(iPrNH2)B8H10XNHiPr] (X=Cl, Br, I). The structures of all three compounds are confirmed by NMR spectroscopy and mass spectrometry, and (for X=Br) by an X-ray diffraction study. The bromoazanonaborane undergoes hydrolytic decomposition to the new five-vertex compound [B5H10(μ-NHiPr)] of hypho-type structure.