Yin Q1, Kemper S1, Klare HF2, Oestreich M3.
Chemistry. 2016 Sep 19;22(39):13840-13844. doi: 10.1002/chem.201603466. Epub 2016 Aug 12.The transition-metal-free hydroboration of various alkenes with pinacolborane (HBpin) initiated by tris[3,5-bis(trifluoromethyl)phenyl]borane (BArF3 ) is reported. The choice of the boron Lewis acid is crucial as the more prominent boron Lewis acid tris(pentafluorophenyl)borane (B(C6 F5 )3 ) is reluctant to react. Unlike B(C6 F5 )3 , BArF3 is found to engage in substituent redistribution with HBpin, resulting in the formation of ArF Bpin and the electron-deficient diboranes [H2 BArF ]2 and [(ArF )(H)B(μ-H)2 BArF2 ]. Read More