In this issue, J. Gascon et al. review metal–organic frameworks: Are they really molecules or rather semiconductors in photocatalysis? The Minireview deals with the carbene-catalyzed asymmetric construction of atropisomers (Y. R. Chi et al.).

In the original research section, Y. Wang et al. report tailoring of the local environment of platinum in single-atom Pt₁/CeO₂ catalysts for robust low-temperature CO oxidation (see picture). R. Buller et al. succeeded in asymmetric cation-olefin monocyclizations by engineered squalene–hopene cyclases. E. Y. Chekmenev et al. describe background-free proton NMR spectroscopy with radiofrequency amplification by stimulated emission radiation, and D. Peña et al. report an on-surface Diels–Alder reaction..

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• Angewandte Chemie 50/2021: Stimulating Chemistry,
  Angew. Chem. Int. Ed. 2021, 60 (50).