Manganese-Catalyzed Oxazoline-Directed C-H Addition of Arenes to Unsaturated Polar Bond: Experimental and Computational Study.

The direct C-H aromatic addition to unsaturated polar bonds using abundant metals such as Mn and Co is scarce, and it has been mainly limited to the use of pyridine as a directing group. In this work, we introduce for the first time the use of oxazoline as a more versatile motif for this transformation, which can be further derivatized in other functional groups. The proposed mechanism shows a base-assisted formation of an Mn-tricarbonyl as the active species in the catalytic cycle, in contrast to the most reported Mn-tetracarbonyl complex. The mechanism was validated by experimental and DFT studies.