ROP artists: The ROP of racemic β‐butyrolactone (BL) catalyzed by highly active chromium(III) salophen complexes 1 gives poly(hydroxybutyrate) (PHB) with high molecular weight and with isotacticities of 60–70 %. The product is a biodegradable polymer material with mechanical properties that can be varied from crystalline to thermoplastic. DFT calculations indicate that the induction of stereochemical information occurs through the formation of dimeric cagelike structures.

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Cover: The cover page shows the formation of polycarbonate formation on solid Zn‐gluterate. Further details can be found in the Full Paper by R. Eberhardt, M. Allmendinger, M. Zintl, C. Troll, G. A. Luinstra, and B. Rieger* on page 42.

Summary: A series of zinc dicarboxylates were synthesized by the reaction of diethylzinc with dicarboxylic acids. Zinc monocarboxylate monoalkyl intermediates were obtained by using a defined excess of diethylzinc over dicarboxylic acid. A subsequent insertion reaction of SO2 into these zinc alkyl bonds resulted in a defined number of Zn‐ethylsulfinate groups, which act as active centers for the copolymerization reaction of CO2 and propylene oxide. Corresponding ethylsulfinic acid ester end groups were detected in the poly(propylene carbonate) (PPC) products. The polymerization activity depended strongly on the number of sulfinate groups incorporated and has been significantly increased compared to conventional zinc dicarboxylates. The obtained PPCs have molecular weights ($\overline M _{\rm w}$) exceeding 80 000 g · mol−1 and polydispersities in the range of 2.3 to 3.3.