Monomeric Octahedral Ruthenium(II) Complex Enabled <i>meta</i>-C–H Nitration of Arenes with Removable Auxiliaries

A removable oxime-assisted meta-C–H nitration of arenes is reported. Mechanistic investigations and DFT calculations reveal a new monomeric octahedral ruthenium­(II) complex is responsible for the meta-selective nitration. Dioxygen as a cooxidant is crucial for achieving high conversion and good yields. Moreover, the utility of the present reaction protocol is further showcased by the late-stage modification of the clinical CNS drugs Diazepam and Fluvoxamine.