Ligand-Enabled “Two-in-One” Metallaphotocatalytic Cross Couplings
Jianbin Li, Ding Zhang, Zheng Hu
Abstract
Metallaphotoredox cross coupling (MCC) is ranking among the most advanced synthetic methodology as it can access chemical space that is difficult to attain under conventional conditions. Earlier developed MCC mandates an independent transition metal catalyst and respective photocatalyst, thus constituting a dual catalytic manifold. Complementarily, a paradigm-shifting metallaphotoredox strategy that capitalizes on a single photoreactive metal complex is emerging, which brings not only operational simplification but also unexpected mechanistic insights. This perspective compiled the recent advances in monocatalytic metallaphotoredox cross couplings and categorized them based on the ligands that confer distinct photoreactivities to various cross coupling mechanisms. To this end, ligand-enabled oxidative addition, transmetalation, reductive elimination and other radical-involving MCC pathways were summarized with notable examples. In this way, we wish to provide a handy guideline for readers who are interested in this emerging field and to inspire more future endeavors for ligand-enabled MCCs and beyond.