O-Directed hydrostannation of b-cyclopropyl propargyl alcohol 22 with stannanes and cat. Et3B in THF/H2O or PhMe/MeOH fails todeliver any detectable products of α-stannylvinyl cation capture. Instead only α-stannyl-β-cyclopropylvinyl radical intermediates canbe detected, which undergo fast H-atom abstraction and/or cyclopropane ring-opening as a result of eliminative β-scission.
Watson, H. A., Manaviazar, S., Steeds, H. G., & Hale, K. J. (2019). Fast ring-opening of an intermediary α-stannyl-β-cyclopropylvinyl radical does not support formation of an α-stannylvinyl cation in the O-directed free radical hydrostannation of dialkyl acetylenes. Chemical Communications. https://doi.org/10.1039/c9cc05492h