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An enantioselective domino process for the synthesis of substituted 1,2‐dihydronaphthalenes has been developed by the combination of chiral amines and a bidentate Lewis acid in an orthogonal catalysis. This new method is based on an inverse electron‐demand Diels−Alder and a subsequent group exchange reaction. An enamine is generated in situ from an aldehyde and a chiral secondary amine catalyst that reacts with phthalazine, activated by the coordination to a bidentate Lewis acid catalyst. The absolute configuration of the product is controlled by chiral information provided by the amine. The formed ortho‐quinodimethane intermediate is then transformed via a group exchange reaction with thiols. The new method shows a broad scope and tolerates a wide range of functional groups with enantiomeric ratios up to 91 : 9. All‐in‐all, this enantioselective synthesis tool provides an easy access to complex 1,2‐dihydronaphthalenes starting from readily available phthalazine, aldehydes and thiols in a combinatorial way. [ABSTRACT FROM AUTHOR]

Abstract: Ein Komplex aus [10]Cycloparaphenylen ([10]CPP) mit dem Bisazafulleren (C59N)2 wurde experimentell und computerchemisch untersucht. In dieser Struktur sind zwei [10]CPP‐Ringe an das dimere Azafulleren gebunden, [10]CPP⊃(C59N)2⊂[10]CPP. Die beobachteten photophysikalischen und Redox‐Eigenschaften lassen auf eine elektronische Interaktion zwischen den Komponenten schließen, insbesondere mit dem zweiten [10]CPP. Im Gegensatz zu [10]CPP⊃C60, in dem nur eine vernachlässigbare elektronische Kommunikation zwischen den Komponenten beobachtet wurde, konnte zwischen dem [10]CPP und dem (C59N)2 durch Lichtanregung ein Ladungstransferphänomen induziert werden, ähnlich einem mit einem CPP eingekapselten Metallofulleren. Solch elektronenreiche Fullerenspezies zeigen C60‐artige Grundzustandseigenschaften und verhalten sich im angeregten Zustand wie Metallofullerene. Diese Eigenschaft eröffnet neue Möglichkeiten für die Konstruktion von funktionalen supramolekularen Architekturen mit organischen Materialien. [ABSTRACT FROM AUTHOR]

Abstract: The complex of [10]cycloparaphenylene ([10]CPP) with bis(azafullerene) (C59N)2 is investigated experimentally and computationally. Two [10]CPP rings are bound to the dimeric azafullerene giving [10]CPP⊃(C59N)2⊂[10]CPP. Photophysical and redox properties support an electronic interaction between the components especially when the second [10]CPP is bound. Unlike [10]CPP⊃C60, in which there is negligible electronic communication between the two species, upon photoexcitation a partial charge transfer phenomenon is revealed between [10]CPP and (C59N)2 reminiscent of CPP‐encapsulated metallofullerenes. Such an alternative electron‐rich fullerene species demonstrates C60‐like ground‐state properties and metallofullerene‐like excited‐state properties opening new avenues for construction of functional supramolecular architectures with organic materials. [ABSTRACT FROM AUTHOR]

This account describes synthetic approaches for curved polycyclic aromatics such as circulenes, helicenes and cycloparaphenylenes, relying on a [2+2+2] cycloaddition. A common feature of all these structures is that their synthesis needs to deviate benzene rings from planarity. Relying on [2+2+2] cycloaddition reactions for this task leads to impressive, and in parts, surprising results. The examples shown here and their optimized reaction conditions contribute to a better understanding of processes going on during the reaction. This knowledge is expected to lead to new designs of challenging syntheses using the [2+2+2] cycloaddition methodology. 1 No Gain, No Strain: Synthesis of Curved Aromatics 2 Examples for the Preparation of Strained Systems Relying on a [2+2+2] Cycloaddition 2.1 Circulenes 2.2 Helicenes 2.3 Cycloparaphenylenes 3 Conclusion and Outlook. [ABSTRACT FROM AUTHOR]

Keywords: Lewis acid catalysis; domino processes; Diels-Alder reaction; mechanistic studies; multicomponent reaction EN Lewis acid catalysis domino processes Diels-Alder reaction mechanistic studies multicomponent reaction 1 1 1 02/23/23 20230217 NES 230217 B The Cover Feature b shows a shot pendulum symbolizing the group transfer reaction studied in our paper. Cover Feature: Mechanistic Studies on the Bidentate Lewis Acid Catalyzed Domino Inverse Electron-Demand Diels-Alder/Thiol Transfer Reaction (Eur. J. Org. Lewis acid catalysis, domino processes, Diels-Alder reaction, mechanistic studies, multicomponent reaction. [Extracted from the article]