In this issue, S. B. Herzon et al. review fragment coupling reactions in total synthesis via carbanionic or free-radical intermediates. M. Scheele et al. summarize research on coupled organic–inorganic nanostructures for charge and energy-transfer applications. The Minireviews deal with designs and structure-property relationships in organo-photocatalysis (Dell’Amico et al.) and radical-based syntheses and modifications of amino acids (A. Gómez-Suárez et al.). In an Essay, C. Wentrup discusses the geochemical works of Robert Bunsen on Icelandic volcanoes and geysers, gas and mineral analyses.

In the original research section, S. Dehnen et al. describe the reactivity and optical properties of organosilicon sulfide clusters (see picture). G. Xu et al. present a MOF-directed synthesis of crystalline ionic liquids with enhanced proton conduction. J. S. Dickschat et al. report on the mechanism of catenul-14-en-6-ol synthase in diterpene biosynthesis. P. Knochel et al. succeeded in regioselective bromine/magnesium exchange for the selective functionalization of polyhalogenated arenes and heterocycles.

• Angewandte Chemie 3/2021: Radicals,
  Angew. Chem. Int. Ed. 2020, 60 (3).