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Anion‐π catalysis functions by stabilizing anionic transition states on aromatic π surfaces, thus providing a new approach to molecular transformation. The delocalized nature of anion–π interactions suggests that they serve best in stabilizing long‐distance charge displacements. Aiming therefore for an anionic cascade reaction that is as charismatic as the steroid cyclization is for conventional cation‐π biocatalysis, reported here is the anion‐π‐catalyzed epoxide‐opening ether cyclizations of oligomers. Only on π‐acidic aromatic surfaces having a positive quadrupole moment, such as hexafluorobenzene to naphthalenediimides, do these polyether cascade cyclizations proceed with exceptionally high autocatalysis (rate enhancements kauto/kcat >104 m−1). This distinctive characteristic adds complexity to reaction mechanisms (Goldilocks‐type substrate concentration dependence, entropy‐centered substrate destabilization) and opens intriguing perspectives for future developments. [ABSTRACT FROM AUTHOR]

A highly enantioselective Mannich reaction of silyl ketene imines with isatin-derived ketimines has been realized by using a chiral N, N′-dioxide/ZnII catalyst. A variety of β-amino nitriles containing congested vicinal tetrasubstituted stereocenters were obtained with excellent outcomes (up to 98 % yield, >19:1 d.r. and 99 % ee). Based on the experimental investigations, a possible transition state has been proposed to explain the origin of the asymmetric induction. [ABSTRACT FROM AUTHOR]

Unter milden Bedingungen und in Gegenwart des Katalysators L/Y(OTf)3 gelang erstmals die Titelreaktion. Über eine 1,2 ‐ Aryl ‐ oder 1,2 ‐ Alkyl ‐ Verschiebung wurden hoch funktionalisierte Succinat ‐ Derivate mit einem quartären Stereozentrum mit ausgezeichneten Ausbeuten und Enantioselektivitäten erhalten. Tf=Trifluormethansulfonyl. [ABSTRACT FROM AUTHOR]