The 11B (I=3/2, abundance ~80%) NMR spectrum of pentaborane-9 consists of a broad signal at -53.5 ppm (relative intensity 1) and another at -13.5 ppm (relative intensity 4). Pentaborane-9 reacts with B2Cl4 to produce B5H8BCl2 (D), which can be converted to B5H8BF2 (E) (i) Use the NMR data below to assign structures to D and E. (Hint - think about the symmetries (2-fold, 3-fold, 4-fold etc) of D, E which are defined by the NMR data). The 14 collected 1H (I=1/2, abundance ~100%), and11B (I=3/2, abundance ~80%) NMR spectral data are given below: