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A highly efficient enantioselective dicarbofunctionalization reaction of (E)-alkenyloxindoles with pyridinium salts was realized. The process includes the chiral N,N′-dioxide–Sc(III) complex-catalyzed regio-, diastereo-, and enantioselective [3+2] cycloaddition reaction and the following photo-promoted aza-Norrish II type rearrangement. A series of 2-pyridyl substituted oxindole derivatives were obtained in good yields with moderate to good diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

An asymmetric one-pot hydrocyanation/Michael reaction of α-aryl diazoacetates with trimethylsilyl cyanide, tert-butanol, and N-phenylmaleimides has been realized. Using a chiral guanidinium salt/CuBr catalyst, a series of cyanide-containing pyrrolidine-2,5-diones could be obtained in good yields with excellent diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

A chiral N,N′-dioxide/Ni(OTf)2 complex-catalyzed asymmetric Diels–Alder reaction of cyclopentadiene with 2,3-dioxopyrrolidines and 2-alkenoyl pyridines has been achieved. The corresponding chiral bridged compounds were obtained in high yields with excellent dr and ee values (up to 97% yield, 95 : 5 dr and 97% ee). [ABSTRACT FROM AUTHOR]

The first iron(iii)/N,N′-dioxide-catalyzed asymmetric haloamination of 3-alkylidene- and 3-arylidene-indolin-2-ones was developed, affording the corresponding chiral oxindole derivatives bearing vicinal haloamine substituents with excellent results (up to 99% yield, 99% ee, ＞19 : 1 dr). This iron catalyst also exhibits perfect enantioselectivity for chalcone derivatives. The cooperative activation of the substrate and the reagent in concert guarantees the high stereoselectivity. [ABSTRACT FROM AUTHOR]

A cooperative bimetallic catalyst system was applied in the catalytic asymmetric cross-dehydrogenative coupling of β-ketoesters and xanthene. Various optically active xanthene derivatives bearing a quaternary stereogenic carbon center were obtained in moderate to good yields (up to 90%) with excellent enantioselectivities (up to 99% ee). Meanwhile, a transition-state model was proposed to explain the origin of the asymmetric induction. [ABSTRACT FROM AUTHOR]

The catalytic asymmetric aza-Michael reaction of benzoyl hydrazine toward chalcones through the nonactivated amine moiety conjugated addition was facilitated by the developed N,N′-dioxide-Sc(OTf)3complex under mild conditions, affording the pharmacologically and synthetically useful products in moderate to high yields with up to 97% ee. [ABSTRACT FROM AUTHOR]