An electrochemically controlled synthesis of multiblock copolymers by alternating the redox states of (salfan)Zr-(O t Bu) 2 (salfan = 1,1′-di(2-tert-butyl-6-N-methylmethylenephenoxy)ferrocene) is reported. Aided by electrochemistry with a glassy carbon working electrode, an in situ potential switch alters the catalyst's oxidation state and its subsequent monomer (Llactide, β-butyrolactone, or cyclohexene oxide) selectivity in one pot. Various multiblock copolymers were prepared, including an ABAB tetrablock copolymer, poly(cyclohexene oxide-b-lactide-bcyclohexene oxide-b-lactide), and an ABC triblock copolymer, poly(hydroxybutyrate-b-cyclohexene oxide-b-lactide). The polymers produced using this technique are similar to those produced via a chemical redox reagent method, displaying moderately narrow dispersities (1.1−1.5) and molecular weights ranging from 7 to 26 kDa.

An aluminum(III) iso‐propoxide complex supported by salfen (1, salfen=1,1′‐di(2,4‐bis‐tert‐butyl‐salicylimino)ferrocene) was synthesized and characterized. Compound 1 can be reversibly oxidized and reduced, and both redox species were surveyed as ring‐opening polymerization catalysts for cyclic esters and cyclohexene oxide. Based on the observed reactivity behavior, 1 could be used as a redox‐switchable catalyst for the formation of AB and ABC type di‐ and triblock copolymers of lactide, cyclohexene oxide, and trimethylene carbonate.

We introduce a new unsymmetric ligand, PDIpCy (PDI = pyridyldiimine; Cy = cyclam), that offers two distinct, noncoupled coordination sites. A series of homo- and heterobimetallic complexes, [Zn(PDIpCy)(THF)(OTf)] (1; THF = tetrahydrofuran and OTf = triflate), [Ni(PDIpCy)(THF)(OTf)](OTf) (2), and [NiZn(PDIpCy)(THF)(OTf)] (3), are described. The one-electron-reduced compounds, [Zn(PDIpCy)(OTF)] (4), [Ni(PDIpCy)(OTf)](OTf) (5), and [NiZn(PDIpCy)(OTf)] (6), were isolated, and their electronic structures were characterized. The reduced compounds are charge-separated species, with electron storage at either the PDI ligand (4) or at the PDI-bound metal ion (5 and 6).

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