Copper-Catalyzed Selective Mononitration of Unbiased <i>ortho</i> -C–H Bonds in Arenes Using a Ball Mill in Air: Excellent Compatibility with Heterocycles

-C-H bonds. Importantly, this work constitutes the first example of C-H bond nitration achieved under mechanochemical conditions as well as the first successful implementation of ball milling in amide-oxazoline-directed transformations. Moreover, the nitration of heteroaromatic systems directed by an amide-oxazolione group had not been previously reported, which has been accomplished in the present study. The developed methodology exhibits a broad substrate scope and high tolerance toward diverse functional groups, including heterocycles, and allows for facile directing group removal from the products. Its practical utility was further demonstrated through gram-scale reaction and various subsequent C-H functionalization and further transformations of the mononitrated products. The practical applicability of this strategy was further illustrated through the late-stage functionalization of telmisartan drug, a well-known antagonist for the angiotensin II receptor. In addition, several control experiments were performed to obtain mechanistic insight and to elucidate the proposed catalytic cycle.