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The article demonstrates Brønsted acid–catalyzed asymmetric dearomatizations via vinylidene–quinone methides. It mentions that reaction allows the practical and atom-economical synthesis of a diverse array of valuable fused polycyclic enones and indolines bearing a chiral quaternary carbon stereocenter and two contiguous stereogenic centers in moderate to good yields with excellent diastereoselectivities and generally excellent enantioselectivities.

A novel gold-catalyzed tandem cycloisomerization/hydrogenation of chiral homopropargyl sulfonamides has been developed. Various enantioenriched pyrrolidines can be obtained in excellent yields and excellent enantioselectivities by combination of chiral tert-butylsulfinimine chemistry with gold catalysis. Importantly, this represents the first example of a pyrrolidine synthesis from homopropargyl sulfonamide. [ABSTRACT FROM AUTHOR]

An efficient yttrium-catalyzed tandem intermolecular hydroalkoxylation/Claisen rearrangement has been developed, providing various γ,δ-unsaturated amides in generally good to excellent yields. Importantly, high Z/E selectivity and diastereoselectivity were achieved. Other notable features of this method include widespread availability of the substrates, compatibility with a broad range of functional groups, and mild reaction conditions. [ABSTRACT FROM AUTHOR]