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A highly efficient catalytic asymmetric [4+2] cycloaddition of silyloxyvinylindoles with β,γ-unsaturated α-ketoesters has been accomplished by an available chiral N,N′-dioxide/yttrium triflate complex. A widespread range of carbazole derivatives were obtained in 47–98% yield with 86–99% ee under mild reaction conditions. [ABSTRACT FROM AUTHOR]

A direct strategy to obtain N-acyl amino acid oxime esters has been developed through the dynamic kinetic resolution of azlactones with oximes. In the presence of a chiral bisguanidinium salt catalyst, a variety of chiral N-acyl amino acid oxime esters were generated in excellent enantiomeric excesses (up to 97%) and high yields (up to 99%). The active oxime esters could be used in dipeptide synthesis. [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]

Enantioselective cyclization of α-isocyano esters with azodicarboxylates catalyzed by FeII–N,N′-dioxide complexes has been developed. Under mild conditions, a variety of 1,2,4-triazoline derivatives was obtained in high yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

Highly enantioselective Michael addition of malonates to β,γ-unsaturated α-ketoesters has been promoted by chiral N,N′-dioxide-Yttrium(iii) complexes, providing the corresponding products in excellent yields with 94–99% eevalues. [ABSTRACT FROM AUTHOR]

A C2-symmetric N,N′-dioxide-Sc(iii) complex has been developed to promote the asymmetric catalytic aldol reaction of α-ketoesters and diazoacetate esters to afford tertiary alcohols in good yields with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]