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Updated: Jul 8, 2026

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Synthesis and Reactivity of Boron Triflate and Bistriflimide Complexes Bearing Two ortho-Carboranes
Kanika Vashisth1, Ragene A Thornton1, Caleb D Martin1
1Baylor University, Department of Chemistry and Biochemistry, One Bear Place #97348, Waco, Texas 76798, United States.
Abstract:
This work discloses the synthesis of boron complexes featuring two 1-methyl-ortho-carborane substituents (MeoCb) and a weakly coordinating pseudohalide, trifluoromethanesulfonate (OTf) or bistriflimide (NTf2). Assessing their Lewis acidity experimentally by NMR probes, OPEt3 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 TfOBMeoCb2 or Tf2NBMeoCb2 with trans-β-nitrostyrene and arenes yield rare 1,4-Michael addition products where the arene acts as the Michael donor.
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