Abstract:

As an emerging motif since the late 90s, borylenes have been a central, yet elusive, point of interest. Free borylenes have been spectroscopically characterized since the 1970s, however, have only recently been isolated as mono and bis(Lewis base)stabilized borylenes. These species possess a +1 oxidation state and differ from classical boron derivatives wherein the formal boron oxidation state is +3. Lewis-base ligated borylenes mimic singlet carbene reactivity and have largely been used as ligands for transition metal catalysis and activation of mild bonds. I propose the in situ generation of borylenes via tandem reduction of dihaloborons in the presence of transition metals. This activation strategy will be used to generate a reactive borylene species which can participate in insertion reactions with unactivated bonds (e.g., C‒H of hydrocarbons, C‒O of THF, borirane on naphthalene). Specifically, this reactive boron species will be used to develop a general C‒N insertion protocol as it is not as well-defined as analogous C‒O and C‒H insertion chemistry. The goal of this proposal is to develop a general amine editing approach via boron insertion.