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The Piancatelli reaction, which is the rearrangement of 2-furylcarbinol to cyclopentenone, involves a key furanoxonium ion intermediate and a furan ring opening-4π electrocyclization process. In recent years, the original oxa-Piancatelli reaction has been extended to a large family of aza- and carbo-Piancatelli reactions and related cascade processes, providing a powerful platform for the construction of diverse functionalized cyclopentenones and polycyclic cyclopentanones. Meanwhile, chiral Brønsted/Lewis acid based catalytic asymmetric approaches to Piancatelli reactions have also been achieved for the assembly of highly valued chiral cyclopentenone scaffolds. In this short review, we present an overview of the recent developments in these areas and focus primarily on reports published in the last five years. 1 Introduction 2 Diastereoselective Oxa-, Aza- and Carbo-Piancatelli Reactions 3 Diastereoselective Cascade Piancatelli Reactions 4 Asymmetric Piancatelli Reactions and Related Cascade Processes 5 Miscellaneous Furanoxonium Ion-Based Rearrangements 6 Conclusion [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]

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]

The catalytic asymmetric halomaminocyclization of sulfamates (I) with NBS and the catalyst CTA provides the syn-products (II) in good selectivity. [ABSTRACT FROM AUTHOR]

A domino thia-Michael/aldol reaction is involved in the title synthesis. [ABSTRACT FROM AUTHOR]

The article presents chemical equations for the article "Catalytic Asymmetric [3 + 2] Cycloaddition of Aromatic Aldehydes with Oxiranes by C—C Bond Cleavage of Epoxides: Highly Efficient Synthesis of Chiral 1,3-Dioxolanes" by W. Chen and others, published in the "Chemical Communications" in 2014.

The article presents chemical structures of indole derivatives representing highly stereoselective conjugate addition and α-Alkynylatin reaction with electron-deficient alkynes catalyzed by chiral scandium(III) complexes.