Cover Picture: Noncovalent Modulation of Chemoselectivity in the Gas Phase Leads to a Switchover in Reaction Type from Heterolytic to Homolytic to Electrocyclic Cleavage (Angew. Chem. Int. Ed. 32/2023)

Diversity in chemical reactivity unfolds even in the gas phase when noncovalent tools such as macrocyclic encapsulation are being used. Two distinct reaction pathways of a multifunctional bicyclic azoalkane (bottom) can be chemoselectively activated inside the cavity of a macrocycle (in gold), leading either to ejection of molecular dinitrogen (top) or ethylene (right), depending on its protonation state. In sharp contrast, the free substrate prefers to eject ammonia upon thermal activation (left), as reported by Werner M. Nau, Elina Kalenius, Tung-Chun Lee et al. in their Research Article (e202303491). Diversity in chemical reactivity unfolds even in the gas phase when noncovalent tools such as macrocyclic encapsulation are being used. Two distinct reaction pathways of a multifunctional bicyclic azoalkane (bottom) can be chemoselectively activated inside the cavity of a macrocycle (in gold), leading either to ejection of molecular dinitrogen (top) or ethylene (right), depending on its protonation state. In sharp contrast, the free substrate prefers to eject ammonia upon thermal activation (left), as reported by Werner M. Nau, Elina Kalenius, Tung-Chun Lee et al. in their Research Article (e202303491). Polyoxometalates Natural Products Glycopeptides Methane Oxidation