One catalyst, two reaction set‐ups, three monomers and unlimited macromolecular microstructural designs: The iron guanidine complex [FeCl2(TMG5NMe2asme)] (1) polymerizes lactide faster than the industrially used Sn(Oct)2 and shows high activity towards glycolide and ϵ‐caprolactone. Its distinguished features enable the synthesis of both block and random‐like copolymers in the melt by a simple change of the polymerization set‐up. Sequential addition of monomers yields highly ordered block copolymers including the symmetrical PLA‐b‐PGA‐b‐PCL‐b‐PGA‐b‐PLA pentablock copolymers, while polymerizations of monomer mixtures feature enhanced transesterifications and pave the way to di‐ and terpolymers with highly dispersed repeating unit distributions. A robust catalyst active under industrially applicable conditions and producing copolymers with desired microstructures is a major step towards biocompatible polymers with tailor‐made properties as alternatives for traditional plastics on the way towards a sustainable, circular material flow.

Electrocatalytic hydrogenation (ECH) produces high-value chemicals from unsaturated organics using water as a hydrogen source. However, ECH is limited by the low solubility of substrates when operated under aqueous conditions, by electrical losses when performed in organic electrolytes and, in general, by low faradaic efficiency and fastidious work-up. Here, we show that a Pickering emulsion compartmenting organic substrates and aqueous electrolytes in different phases enables efficient ECH at the interface. We designed a construct comprising Pd nanoparticles immobilized on positively charged carbon nanotubes that localizes at the interface to act as both emulsion stabilizer and electrocatalyst. Applied to the ECH of styrene, the system delivers ethylbenzene at high faradaic efficiency (95.0%) and mass specific current density (–148.1 mA  $${{{\mathrm{mg}}}}_{{{{\mathrm{Pd}}}}}^{ - 1}$$ mg Pd − 1 ). The system combines good substrate solubility, high conductivity and simplified product isolation, and has proved applicable to the conversion of various alkenes. This strategy may thus provide alternative solutions to the ECH of substrates with low water solubility, such as bio-oil and bio-crude.

The iron guanidine catalyst …s hows extraordinary copolymerization activity towards lactide,g lycolide,a nd e-caprolactone,a sr eported by Sonja Herres-Pawlis,M oshe Kol, and co-workers in their Research Article (e202112853). Depending on the reaction temperature and the mode of monomer addition, it either forms up to pentablock copolymers in ah ighly defined way or promotes transesterifications to such ah igh degree that random copolymers are produced. Therefore,i ti sarare example of ac atalyst mastering both microstructures:o rdered and chaotic.

Der Eisen‐Guanidin‐Katalysator zeigt eine außergewöhnliche Copolymerisationsaktivität gegenüber Lactid, Glycolid und ϵ‐Caprolacton, wie Sonja Herres‐Pawlis, Moshe Kol et al. in ihrem Forschungsartikel berichten (e202112853). Je nach Reaktionstemperatur und Art der Monomerzugabe bildet er entweder hoch definierte Pentablock‐Copolymere oder fördert Umesterungen in so starkem Ausmaß, dass randomisierte Copolymere entstehen. Damit ist er ein seltenes Beispiel für einen Katalysator, der beide Mikrostrukturen beherrscht: geordnet und chaotisch.