Push–Pull Activation of N ₂ : Coordination of Lewis Acids to Dinitrogen Complexes

Abstract This article gathers, as of 2020, examples of (hetero)dinuclear dinitrogen complexes that are formed by Lewis acid (LA)–base interaction thanks to dative bonding between an electron‐deficient s‐, p‐, or d‐block species and the electron‐rich terminal nitrogen of a neutral end‐on dinitrogen complex. LA coordination to the dinitrogen ligand results in a higher level of activation (i.e. polarization) according to a push–pull mechanism: electron depletion induced by LA coordination amplifies electron back‐donation. The magnitude of such phenomenon will depend on various factors that will be highlighted here, as well as the mean to measure it. In some instances, key reactivities that LA coordination has lent to the dinitrogen complex, or how their combination has allowed the discovery of original reactions will be discussed. This article is organized in three main sections according to which block of the periodic system the LA component of the complexes discussed belongs to. In a final section, pieces of work issued from main group chemistry and relevant in the context of N 2 push–pull activation will be presented.