Oxidative aromatic coupling occupies a fundamental place in the modern chemistry of aromatic compounds. It is a method of choice for the assembly of large and bewildering architectures. Considerable effort was also devoted to applications of the Scholl reaction for the synthesis of chiral biphenols and natural products. The ability to form biaryl linkages without any prefunctionalization provides an efficient pathway to many complex structures. Although the chemistry of this process is only now becoming fully understood, this reaction continues to both fascinate and challenge researchers. This is especially true for heterocoupling, that is, oxidative aromatic coupling with the chemoselective formation of a C−C bond between two different arenes. Analysis of the progress achieved in this field since 2013 reveals that many groups have contributed by pushing the boundary of structural possibilities, expanding into surface‐assisted (cyclo)dehydrogenation, and developing new reagents.

Indolizine (pyrrolo[1,2-a]pyridine) is one of the five isomers of indole and it serves as a precursor for widespread indolizidine alkaloids. The straightforward synthesis of indolizines based on classical methodologies such as Scholtz or Chichibabin reactions has overshadowed numerous new strategies that have been revealed especially within the last ten years. The desire to achieve substitution patterns which were hard to build sparked the discovery of completely new pathways, e.g. transition metal-catalyzed reactions and approaches based on oxidative coupling. In this review, selected strategies toward indolizines published since 2005 are briefly summarized, commented upon, compared, and illustrated. The literature discussed here involves reactions based on either pyridine or pyrrole scaffolds, as well as selected methodologies leading to π-expanded indolizines.

Die oxidative aromatische Kupplung nimmt einen grundlegenden Platz in der modernen Arenchemie ein. Sie ist das Mittel der Wahl für den Aufbau großer, komplizierter Molekülarchitekturen. Auch die Scholl‐Reaktion und ihre Anwendungen in der Synthese chiraler Biphenole und Naturstoffe sind stark beforscht. Die Möglichkeit, Biarylverknüpfungen ohne Vorfunktionalisierung herzustellen, bietet einen effizienten Weg zu vielen komplexen Strukturen. Obwohl die Chemie hinter diesem Prozess erst jetzt nach und nach voll verstanden wird, ist er weiterhin eine Quelle der Inspiration. Dies trifft besonders auf Heterokupplungen zu, d. h. oxidative, aromatische Kupplungen unter chemoselektiver C‐C‐Bindungsbildung zwischen zwei verschiedenen Arenen. Eine Analyse der Fortschritte in diesem Feld seit 2013 zeigt, dass zahlreiche Gruppen hierzu beigetragen haben – durch die Entdeckung neuer struktureller Möglichkeiten, die Erweiterung zu oberflächengestützten (Cyclo)dehydrierungen und die Entwicklung neuer Reagenzien.

Introducing moderate charge-transfer character into nitro-aromatics is a key to producing strong fluorescence.

This review describes recent advances in the generation of aryl radicals using light and electricity. Such modern techniques allow for efficient energy and resource utilization, thus providing more sustainable radical arylation methods.