Synthesis and Reactivity of Boron Triflate and Bistriflimide Complexes Bearing Two ortho -Carboranes

High Resolution Image Download MS PowerPoint Slide This work discloses the synthesis of boron complexes featuring two 1-methyl- ortho -carborane substituents ( Me o Cb) and a weakly coordinating pseudohalide, trifluoromethanesulfonate (OTf) or bistriflimide (NTf 2 ). Assessing their Lewis acidity experimentally by NMR probes, OPEt 3 and 4-fluorobenzonitrile, revealed they are highly electrophilic, and DFT computations place their fluoride affinity in the Lewis super acidic regime. The fluoride affinity is leveraged in catalytic C–F Friedel–Crafts reactions. The three-component reactions of TfOB Me o Cb 2 or Tf 2 NB Me o Cb 2 with trans -β-nitrostyrene and arenes yield rare 1,4-Michael addition products where the arene acts as the Michael donor.