C−X bond reductive elimination and oxidative addition are key steps in many catalytic cycles for C−H functionalization catalyzed by precious metals; however, engaging first row transition metals in these overall 2e − processes remains a challenge. Although high-valent Mn aryl species have been implicated in Mn-catalyzed C−H functionalization, the nature and reactivity of such species remain unelucidated. In this work, we report rare examples of stable, cyclometalated monoaryl Mn III complexes obtained through clean oxidative addition of Ar−Br to Mn I (CO) 5 Br. These isolated Mn III −Ar complexes undergo unprecedented 2e − reductive elimination of the Ar−X (X = Br, I, and CN) bond and Mn II induced by 1e − oxidation, presumably via transient reactive Mn IV species. Mechanistic studies suggest a nonradical pathway.

Single and double dearomatization of pyridine rings was observed in MnI complexes with an N2S2 pyridinophane ligand via deprotonation of one or two CH2 arms, respectively.

We report a series of ruthenium complexes with a tetradentate N,S-donor ligand, 2,11-dithia[3.3](2,6)pyridinophane (N2S2) that undergo single and double deprotonation in the presence of a base leading to the deprotonation...