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Vinylcyclopropanes (VCPs) are commonly used in transition‐metal‐catalyzed cycloadditions, and the utilization of their recently realized reactivities to construct new cyclic architectures is of great significance in modern synthetic chemistry. Herein, a palladium‐catalyzed, visible‐light‐driven, asymmetric [5+2] cycloaddition of VCPs with α‐diazoketones is accomplished by switching the reactivity of the Pd‐containing dipolar intermediate from an all‐carbon 1,3‐dipole to an oxo‐1,5‐dipole. Enantioenriched seven‐membered lactones were produced with good reaction efficiencies and selectivities (23 examples, 52–92 % yields with up to 99:1 er and 12.5:1 dr). In addition, computational investigations were performed to rationalize the observed high chemo‐ and periselectivities. [ABSTRACT FROM AUTHOR]

Vinylcyclopropanes (VCPs) are commonly used in transition‐metal‐catalyzed cycloadditions, and the utilization of their recently realized reactivities to construct new cyclic architectures is of great significance in modern synthetic chemistry. Herein, a palladium‐catalyzed, visible‐light‐driven, asymmetric [5+2] cycloaddition of VCPs with α‐diazoketones is accomplished by switching the reactivity of the Pd‐containing dipolar intermediate from an all‐carbon 1,3‐dipole to an oxo‐1,5‐dipole. Enantioenriched seven‐membered lactones were produced with good reaction efficiencies and selectivities (23 examples, 52–92 % yields with up to 99:1 er and 12.5:1 dr). In addition, computational investigations were performed to rationalize the observed high chemo‐ and periselectivities. [ABSTRACT FROM AUTHOR]

Catalytic asymmetric cycloadditions of ambident Pd‐containing dipolar species with nucleophilic dipolarophiles, namely, inverse‐electron‐demand cycloadditions, are challenging and underdeveloped. Possibly, the inherent linear selectivity of Pd‐catalyzed intermolecular allylations and the lack of efficient chiral ligands are responsible for this limitation. Herein, two cycloadditions of such intermediates with deconjugated butenolides and azlactones were accomplished by using a novel chiral hybrid P,S‐ligand and hydrogen bonding. By doing so, highly functionalized, optically active dihydroquinol‐2‐ones were produced with generally high reaction efficiencies and selectivities. Preliminary DFT calculations were performed to explain the high enantio‐ and diastereoselectivities. [ABSTRACT FROM AUTHOR]

Catalytic asymmetric cycloadditions of ambident Pd‐containing dipolar species with nucleophilic dipolarophiles, namely, inverse‐electron‐demand cycloadditions, are challenging and underdeveloped. Possibly, the inherent linear selectivity of Pd‐catalyzed intermolecular allylations and the lack of efficient chiral ligands are responsible for this limitation. Herein, two cycloadditions of such intermediates with deconjugated butenolides and azlactones were accomplished by using a novel chiral hybrid P,S‐ligand and hydrogen bonding. By doing so, highly functionalized, optically active dihydroquinol‐2‐ones were produced with generally high reaction efficiencies and selectivities. Preliminary DFT calculations were performed to explain the high enantio‐ and diastereoselectivities. [ABSTRACT FROM AUTHOR]