Data for unwrapping a dodecaboranes’ B12 core: A structure, electronic property, and chemical reactivity study over the holistic series of [B12In]– (n = 11–1)

<p>Successively stripping the exohedral substituents from the stable <i>closo</i>-dodecaborate anion [B<sub>12</sub>I<sub>12</sub>]<sup>2–</sup> results in structural transformations of the icosahedral B<sub>12</sub><sup> </sup>into a (quasi-)planar unsubstituted B<sub>12</sub><sup>0/–</sup> unit. Previous studies have finally pinpointed the first ions with an open B<sub>12</sub> unit to [B<sub>12</sub>I<sub>7</sub>]<sup>–</sup>, but further transitions in geometry, electronic structure and chemical reactivity across the whole range of fragments [B<sub>12</sub>I<sub>n</sub>]<sup>–</sup> (n = 11–1) remained elusive. Herein, we report a systematic investigation to explore the chemical properties of these intermediate structures using negative ion photoelectron spectroscopy (NIPES), ion mobility spectrometry (IMS), ion-molecule reactions, and quantum chemical calculations. [B<sub>12</sub>I<sub>n</sub>]<sup>–</sup> ions can be categorized into three groups: (1) very reactive fragments with intact (quasi-)icosahedral B<sub>12</sub>-cages (n = 11–8), (2) less reactive open structures (n = 7–4), and (3) almost unreactive (quasi-)planar structures (n = 3–1). Preparative mass spectrometry shows that the unsaturated B<sub>12</sub> core of category (2) ions tends to form smaller fully substituted <i>closo</i>-borate anions [B<sub>m</sub>X<sub>m</sub>]<sup>2–</sup> (m=6-11 with X=I, H, OH) on surfaces. In contrast, category (3) ions fully decay, and no ions were found on surfaces. This research provides fundamental insights into physical and chemical properties of B<sub>12</sub> units depending on their substitution level and paves the way for the rational design of boron-rich compounds using unconventional [B<sub>12</sub>I<sub>n</sub>]<sup>–</sup> building blocks.</p>

<p>The raw data was collected on a Thermo linear quadrupole ion trap mass spectrometer and the files are named in the following order: mode of ionization, ionization source, name of the neutral reagent, targeted ion of interest and the isolation steps. </p>