Box-copper catalyzed cascade asymmetric amidation for chiral exo-methylene aminoindoline derivatives.

Enantioselective copper-catalyzed cascade inter- and intramolecular amidation was achieved between ethynyl benzoxazinanones and α-halohydroxamates in the presence of an indapybox ligand. The one-pot cascade transformation was triggered by the attack of hydroxamates to dipolar copper-allenylidene intermediates, followed by a nucleophilic annulation reaction. Thus, a series of exo-methylene 3-aminoindoline derivatives were obtained in good yields with high enantioselectivities under mild reaction conditions.

Chiral Bidentate Phosphoramidite-Pd Catalyzed Asymmetric Decarboxylative Dipolar Cycloaddition for Multistereogenic Tetrahydrofurans with Cyclic N-Sulfonyl Ketimine Moieties.

An asymmetric [3 + 2] cycloaddition of vinyl ethylenecarbonates (VECs) and (E)-3-arylvinyl substituted benzo[d] isothiazole 1,1-dioxides has been developed using the Pd complex of a bidentate phosphoramidite (Me-BIPAM) as the catalyst, providing a wide variety of chiral multistereogenic vinyltetrahydrofurans in good yields with excellent diastereo- and enantioselectivities (up to >20:1 dr, 99% ee).

Chiral Binaphthyl Box-Copper-Catalyzed Enantioselective Tandem Michael-Ketalization Annulations for Optically Active Aryl and Heteroaryl Fused Bicyclicnonanes.

The combination of chiral binaphthyl box-copper(II) with triflimide (Tf2NH) was identified as an efficient catalytic system for the asymmetric Michael/ketalization of (E)-2-hydroxyaryl-2-oxobut-3-enoates or (E)-ethyl 4-(2-aminoaryl)-2-oxobut-3-enoates with pyrazolone derivatives. The corresponding asymmetric tandem reactions provided a series of enantioenriched aryl and heteroaryl fused 2,8-O,O- or O,N-bicyclo[3.3.1]nonanes in high yields with excellent enantio- and diastereoselectivities.

Chiral N-Heterocyclic-Carbene-Catalyzed Cascade Asymmetric Desymmetrization of Cyclopentenediones with Enals: Access to Optically Active 1,3-Indandione Derivatives.

A chiral N-heterocyclic-carbene-catalyzed cascade asymmetric desymmetrization reaction of cyclopentenediones with enals has been successfully initiated, followed with tandem aldol annulation, aromatization, as well as sequential methylation. The reactions proceeded well under mild reaction conditions, with broad substrate scope and good functional group tolerance, providing a rapid access to highly functionalized chiral 2,2-disubstituted 1,3-indandione derivatives containing an all-carbon quaternary stereogenic center in moderate to good yields with high enantioselectivities.