[1-H₂N−CB₁₁F₁₁]^- − Synthesis and Reactions of a Functionalized Fluorinated Carbadodecaborate Anion

In anhydrous hydrogen fluoride, K[1-H2N−CB11H11] is fluorinated with elemental fluorine to produce K[1-H2N−CB11F11]. Under strong alkaline conditions, two fluorine atoms of the [1-H2N−CB11F11]- anion are regioselectively exchanged, yielding the [1-H2N-4,6-(HO)2−CB11F9]- anion via [1-H2N-6-HO−CB11F10]- as an intermediate. Both hydroxycarborate anions were isolated as [Ph4P]+ salts. All of the species were characterized by IR, Raman, and multi-NMR spectroscopy, thermal analysis (DSC) as well as by mass spectrometry (MALDI). The assignment of the NMR signals was supported by DFT calculations. Solid-state structures of K[1-H2N−CB11F11], [BzPh3P][1-H2N−CB11F11], [Ph4P][1-H2N-4,6-(HO)2−CB11F9], [Ph4P][1-H2N-6-HO−CB11F10], and [BzPh3P][1-H2N−CB11H11] were determined by single-crystal X-ray diffraction.