Stable Borocyclic Radicals via Frustrated Lewis Pair Hydrogenations

The synthesis and isolation of stable main group radicals remains an ongoing challenge. Here we report the application of frustrated Lewis pair chemistry to the synthesis of boron-containing radicals. H-2 activation with polyaromatic diones and 13(C6F5)(3) leads to radical formation in good yields. These or are robust; they do not decompose on silica gel or react with 02 and are stable at 35 degrees C under N-2 indefiritely. The mechanism of formation is explored experimentally, with support from DFT calculations. EPR and. UV/vis spectroscopy as well as cyclic voltarnmetry data are provided, and the radicals are shown to react with cobaltocenes in one-electron chemical reductions to their,corresponding borate anions.