Triply convergent Ni-electrocatalytic assembly of 1,1-diaryl cyclobutanes, azetidines and oxetanes

The pursuit of increasingly complex, three-dimensional molecules is pushing the boundaries of modern organic synthesis, particularly in drug discovery where rigid, saturated scaffolds such as cyclobutanes, azetidines and oxetanes are in high demand. Here we outline a modular, scalable, chemoselective approach to solve this problem using simple α-bromoacids and aryl halides as intuitive starting materials. As demonstrated herein, a sequential series of nickel-electrocatalytic cross-couplings can be enlisted to enable rapid access to such structures, many of which have been nearly impossible to access before without recourse to time-consuming polar bond disconnections that are inherently limiting in terms of accessible chemical space. The scalability of this new reaction sequence is demonstrated, alongside direct applications to known patented structures. A simple user guide is also presented to accelerate adoption of this strategy in medicinal chemistry and related fields.