A Strategy for Site- and Chemoselective C-H Alkenylation through Osmaelectrooxidative Catalysis

Herein, we disclose osmaelectrocatalyzed C-H activations that set the stage for electrooxidative alkyne annulations by benzoic acids. The osmium electrocatalysis enables site- and chemoselective electrooxidative C-H activations with unique levels of selectivity. The isolation of unprecedented osmium(0) and osmium(II) intermediates, along with crystallographic characterization and analyses by spectrometric and spectroscopic in operando techniques delineate a synergistic osmium redox catalyst regime. Detailed mechanistic studies revealed a facile C-H cleavage, which allows for an ample substrate scope, providing provide robust and user-friendly access to annulated heterocycles.

Automated summary

The research reveals osmaelectrocatalyzed C-H activations using benzoic acids, enabling electrooxidative alkyne annulations with high levels of selectivity. Unprecedented osmium(0) and osmium(II) intermediates were isolated, and detailed mechanistic studies unveiled a facile C-H cleavage and ample substrate scope for annulated heterocycles synthesis.