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The atroposelective transformation of alkynes is an efficient protocol for the assembly of axially chiral compounds. Benefitting from the rapid development of chiral organocatalysts, the organocatalytic atroposelective reactions of alkynes have been extensively studied over the past decades. An array of chiral catalysts, including chiral Brønsted acid catalysts, secondary amine catalysts, N -heterocyclic carbene (NHC) catalysts, thiourea catalysts and N -squaramide catalysts, are employed in enantioselective reactions of different alkynes. This short review summarizes the recent advances on organocatalytic atroposelective reactions of alkynes according to the type of alkyne substrate. The reaction mechanisms, modes of enantiocontrol, product diversity and applications are highlighted. 1 Introduction 2 Electron-Rich Aryl Alkynes 3 Electron-Deficient Aryl Alkynes 4 Other Types of Alkynes 5 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

Diynes and multiynes have proven to versatile synthons for the synthesis of a range of useful cyclic compounds, especially functionalized complicated polycyclic skeletons comprising carbocycles and heterocycles. Axially chiral compounds, one of the most significant class of compounds featuring axial chirality, are widely existed in natural products and pharmaceuticals as well as chiral ligands and chiral catalysts. Over the past decades, numerous of synthetic protocols have been established for the atroposelective synthesis of axially chiral compounds. However, the catalytic asymmetric atroposelective reaction of diynes and multiynes has been rarely investigated and there is no systematic brief up to now. In this review, we summarize the advances in the attainments of the catalytic asymmetric reaction of diynes and multiynes for the construction of axially chiral compounds, and also propose the remained challenges and opportunities for future breakthroughs in this field. [ABSTRACT FROM AUTHOR]

The enantioselective transformation of easily accessible 1,2-diketones represents a quick pathway towards enantioenriched molecules. Herein, we disclose a copper-catalyzed atroposelective formal [4+1] annulation of 1,2-diketones with vinyl cations, enabling the efficient and atom-economical construction of axially chiral arylpyrroles bearing 1,3-dioxole moieties with good to excellent enantioselectivities under mild reaction conditions. Importantly, this methodology constitutes the first enantioselective formal [4+1] annulation of 1,2-diketones. [ABSTRACT FROM AUTHOR]

The regioselective transformation of alkynes represents a highly efficient bond-forming strategy in organic synthesis. However, the enantiocontrol in the conversion of alkynes remains challenging, especially for the metal-free approach. Herein, we describe a chiral Brønsted acid-catalyzed enantioselective spirocyclization of alkynyl thioethers via dearomatization of phenols. This metal-free protocol leads to the green and atom-economical preparation of chiral spiro[4.5]decan-6-ones in good to excellent yields with high enantioselectivities. Importantly, this protocol represents the first metal-free example of the asymmetric transformation of alkynyl thioethers. [ABSTRACT FROM AUTHOR]

The article explores recent advancements in the asymmetric Doyle-Kirmse reaction, a chemical reaction that produces chiral sulfides. It discusses different strategies and catalysts used to achieve high enantioselectivity in the reaction, as well as the role of chiral metal-bound ylides in controlling the stereoselectivity. The text also highlights the challenges and future directions for further development in this area. Overall, the article provides valuable insights into the current state and potential future advancements in this field of research. [Extracted from the article]