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Herein, we leverage the Ni-catalyzed enantioselective reductive dicarbofunctionalization of internal alkenes with alkyl iodides to enable the synthesis of chiral pyrrolidinones bearing vicinal stereogenic centers. The application of newly developed 1-Nap Quinim is critical for formation of two contiguous stereocenters in high yield, enantioselectivity, and diastereoselectivity. This catalytic system also improves both the yield and enantioselectivity in the synthesis of α,α-dialkylated γ-lactams. Computational studies reveal that the enantiodetermining step proceeds with a carbamoyl-NiI intermediate that is reduced by the Mn reductant prior to intramolecular migratory insertion. The presence of the t-butyl group of the Quinim ligand leads to an unfavorable distortion of the substrate in the TS that leads to the minor enantiomer. Calculations also support an improvement in enantioselectivity with 1-Nap Quinim compared to p-tol Quinim.

We present an intramolecular [3+2] cycloaddition of innovative (E)-α-aryl enal derivatives with 4-aminopyrazolone hydrochlorides/3-aminooxindole hydrochlorides to afford an array of atropisomeric benzoxepinone-based styrenes fused to spiro[pyrrolidine–pyrazolone/oxindole] scaffolds, and kinetic resolutions of the racemic adducts were implemented by reacting with benzyl alcohols, giving the corresponding two types of axially chiral styrenes in enantioenriched form with high s-factor. In addition, product transformations such as oxidative dehydrogenation and cross-coupling reactions have been demonstrated. [ABSTRACT FROM AUTHOR]

A new strategy for the asymmetric allylic alkylation of azlactones with α-(trifluoromethyl)allyl acetates catalyzed by Pd(OAc)2 /(R)-BINAP is designed and developed, providing access to unsaturated α-quaternary α-amino acid derivatives bearing a trifluoromethyl group and contiguous quaternary and tertiary stereogenic centers. The products are obtained in good yields with exclusive regioselectivity and excellent stereoselective control under relatively mild reaction conditions. A scale-up experiment shows no loss of reactivity or stereoselectivity. The synthetic utility of the current strategy is demonstrated through transformations of a representative product to afford several potentially bioactive species. [ABSTRACT FROM AUTHOR]

A straightforward [3+2] annulation method for synthesizing bisspiro(oxindole) derivatives has been developed by using isatin‐derived Morita‐Baylis‐Hillman carbonates and p‐quinone methides (p‐QMs) with 4‐dimethylaminopyridine (DMAP) as the catalyst. The optimized protocol in dichloromethane (DCM) solvent achieves good yields (up to 87 %) and diastereoselectivity (>20 : 1). The versatility of the method is shown through the synthesis of various derivatives, including chiral variants with up to 82 % ee. The intermediates were captured by HRMS, and a plausible reaction pathway was proposed. [ABSTRACT FROM AUTHOR]

A catalytic asymmetric (3+2) cyclization of pyrazolone‐based MBH adducts with alkylidenyl isoxazolones was presented by using DMAP‐derived chiral catalyst, affording bis‐spirocyclic pyrazolones bearing vicinal all‐carbon quaternary stereocenters within an imbedded cyclopentene ring scaffold in good yields with excellent stereoselectivities under mild conditions. [ABSTRACT FROM AUTHOR]

β‐Tertiary amino acid derivatives constitute one of the most frequently occurring units in natural products and bioactive molecules. However, the efficient asymmetric synthesis of this motif still remains a significant challenge. Herein, we disclose a cobalt‐catalyzed enantioselective reductive addition reaction of ketimine using α‐chloro carbonyl compound as a radical precursor, providing expedient access to a diverse array of enantioenriched β‐quaternary amino acid analogues. This protocol exhibits outstanding enantioselectivity and broad substrate scope with excellent functional group tolerance. Preliminary mechanism studies rule out the possibility of Reformatsky‐type addition and confirm the involvement of radical species in stereoselective addition process. The synthetic utility has been demonstrated through the rapid assembly of iterative amino acid units and oligopeptide, showcasing its versatile platform for late‐stage modification of drug candidates. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Transition metal‐catalyzed carbometallation of unsaturated hydrocarbons constitutes one of the most efficient synthetic methodologies for the construction of C—C bond. Recently, the incorporation of organometallic reagent with the CO gas as a nucleophilic acyl synthon could enable the acylmetallation reaction, which greatly increases the horizon of carbometallation chemistry. Herein, we report a nickel‐catalyzed regiodivergent acylzincation of o‐cyano cinnamate ester and o‐cyano styrene, in which the cyano moiety intramolecularly captures zinc intermediates to trigger the tandem cyclization process. This protocol features mild conditions, broad substrate scope and excellent functional group tolerance, thus affording a diverse array of highly functionalized carbocyclic compounds. [ABSTRACT FROM AUTHOR]