Interactions Between Two Cobalt Salen Centers Bridged by Non‐Conjugated Linkers**

Abstract

Tetra‐tert‐butyl‐Co(salen), an amido‐substituted derivative and a series of bis(salen) complexes of cobalt(II) with the two metal centers bridged by flexible, non‐conjugated bis‐amido linkers are investigated by cyclic voltammetry, chronoamperometry, and differential pulse voltammetry in four electrolytes (acetonitrile or dichloromethane, conventional or weakly coordinating anion). Cyclic voltammograms are analyzed by simulation based on E or EE mechanisms. The compounds are characterized by formal potentials E0 , diffusion coefficients D and number of electrons transferred, n. Differences in the E0 values for the subsequent two one‐electron transfer steps are used as indicators for the interaction between the metal centers in the bis(salen) complexes. The effects of solvent and supporting electrolyte are consistent with the assumption of electrostatic through‐space interactions and coordination to the Co centers. In the dinuclear complexes step‐wise electron transfers according to normal potential ordering makes these compounds “pretenders” in Winter's terms (R.F. Winter, Organometallics 2014, 33, 4517–4536).

Pushing the redox potentials of deelectronators to highly positive values using solvent effects and weakly coordinating anions

“…43,44 More than 100 groups worldwide utilize the advantageous properties of [pf]and closely related WCAs for applications in diverse fields, i.e. deelectronation, 45 supporting [46][47][48] and battery [49][50][51][52][53] electrolytes, organic solar cells, [54][55][56] photoacids, 57 catalysis, 58 etc. [59][60][61] This account reports, how the above ion-pairing and solvent problems upon application of de + salts are overcome by using strategically substituted and dipole-maximized polar fluorobenzenes 62 xFB (x = 1-5) partnered with salts of the large 63 redox-stable WCAs [pf]and [al-f-al]shown in Figure 1.…”