The Reductive Addition–Oxidative Elimination Mechanism

The oxidative addition–reductive elimination (OARE) mechanism of reactive molecules on metal atoms is a cornerstone of modern chemistry. However, the complementary reductive addition–oxidative elimination (RAOE) mechanism is barely considered, despite a first reduction reaction between metal atoms and the incoming organic reactant makes chemical sense in a plethora of processes. Here we show, in a chronological order, early precedents in the literature which indicated the possibility of a general RAOE mechanism, the few systems explicitly reported so far (including a catalytic system) and some other reactions where a RAOE mechanism would satisfactorily explain the mechanistic evidences found. These examples, together, strongly suggest that researchers should consider the RAOE mechanism during their investigations, and not simply adjust their conclusions to the omnipresent OARE mechanism. This new line of thinking might open new avenues in the design of chemical reactions, particularly catalytic ones.