Deconstructive Functionalizations of Unstrained Carbon–Nitrogen Cleavage Enabled by Difluorocarbene

Transition-metal- or oxidant-promoted
deconstructive functionalizations of noncyclic carbon–nitrogen
bonds are well established, usually only leaving one moiety functionalized
toward the final product. In contrast, concomitant C- and N-functionalizations
via the unstrained C­(sp3)–N bond under metal- and
oxidant-free conditions are very rare, which would favorably confer
versatility and product diversity. Disclosed herein is the first difluorocarbene-induced
deconstructive functionalizations embodying successive C­(sp3)–N bond cleavage of cyclic amines and synchronous functionalization
of both constituent atoms which would be preserved in the eventual
molecular outputs under transition-metal-free and oxidant-free conditions.
Correspondent access to deuterated formamides with ample isotopic
incorporation was demonstrated by a switch to heavy water which is
conceivably useful in pharmaceutical sciences. The current strategy
remarkably administers a very convenient, operationally simple and
novel method toward molecular diversity from readily available starting
materials. Therefore, we project that these findings would be of broad
interest to research endeavors encompassing fluorine chemistry, carbene
chemistry, C–N bond activation, as well as medicinal chemistry.