Cover Picture: Synthesis of Azepine Derivatives by Rhodium-Catalyzed Tandem 2,3-Rearrangement/Heterocyclization (Angew. Chem. Int. Ed. 43/2012)



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Heterocycle construction through the formation of an azametallacycle from an N-allenylnitrone intermediate is demonstrated in the Communication of I. Nakamura et al. on page 10816 ff. The inherently unstable intermediate can be generated in situ by catalytic 2,3-rearrangement from O-propargylic oximes. This tandem reaction can be compared to a flying trapeze knee hang maneuver.