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Organic molecules bearing chiral sulfur stereocenters exert a great impact on asymmetric catalysis and synthesis, chiral drugs, and chiral materials. Compared with acyclic ones, the catalytic asymmetric synthesis of thio‐heterocycles has largely lagged behind due to the lack of efficient synthetic strategies. Here we establish the first modular platform to access chiral thio‐oxazolidinones via Pd‐catalyzed asymmetric [3+2] annulations of vinylethylene carbonates with sulfinylanilines. This protocol is featured by readily available starting materials, and high enantio‐ and diastereoselectivity. In particular, an unusual effect of a non‐chiral supporting ligand on the diastereoselectivity was observed. Possible reaction mechanisms and stereocontrol models were proposed. [ABSTRACT FROM AUTHOR]

The exploration of value‐added conversions of naturally abundant amino acids has received considerable attention from the synthetic community. Compared with the well‐established asymmetric decarboxylative transformation, the asymmetric deaminative transformation of amino acids still remains a formidable challenge, mainly due to the lack of effective strategies for the C−N bond activation and the potential incompatibility with chiral catalysts. Here, we disclose a photoinduced Cu‐catalyzed asymmetric deaminative coupling reaction of amino acids with arylboronic acids. This new protocol provides a series of significant chiral phenylacetamides in generally good yields and excellent stereoselectivity under mild and green conditions (42–85 % yields, up to 97 % ee). Experimental investigations and theoretical calculations were performed to reveal the crucial role of additional phenols in improving catalytic efficiency and enantiocontrol. [ABSTRACT FROM AUTHOR]

Keywords: chiral allene; medium-sized ring; cycloaddition; Cope rearrangement; asymmetric catalysis EN chiral allene medium-sized ring cycloaddition Cope rearrangement asymmetric catalysis 1845 1851 7 09/15/23 20231004 NES 231004 Graph 1 Introduction Allene is a unique functional group with a three-carbon structure consisting of two I sp i SP 2 sp -hybridized terminal carbons and one I sp i -hybridized inner carbon (Scheme 1a). Since the correct structure and axial chirality of allenes was first predicted by the pioneer van't Hoff in 1875, [2] allenes have attracted continuous research interest from synthetic chemists for over a century, driven by the curiosity of their unique structure. [24] Another method to synthesize the 1,3-endocyclic allenes is the cyclization of skillfully designed acyclic allenes; but this is not applicable to the preparation of cyclic allenes with smaller rings. [Extracted from the article]

Catalytic asymmetric synthesis of chiral endocyclic allenes remains a challenge in allene chemistry owing to unfavored tension and complex chirality. Here, we present a new relay strategy merging Pd‐catalyzed asymmetric [3+2] annulation with enyne‐Cope rearrangement, providing a facile route to chiral 9‐membered endocyclic allenes with high efficiency and enantioselectivity. Moreover, theoretical calculations and experimental studies were performed to illustrate the critical, but unusual Cope rearrangement that allows for the complete central‐to‐axial chirality transfer. [ABSTRACT FROM AUTHOR]

Vinylcyclopropanes (VCPs) are commonly used in transition‐metal‐catalyzed cycloadditions, and the utilization of their recently realized reactivities to construct new cyclic architectures is of great significance in modern synthetic chemistry. Herein, a palladium‐catalyzed, visible‐light‐driven, asymmetric [5+2] cycloaddition of VCPs with α‐diazoketones is accomplished by switching the reactivity of the Pd‐containing dipolar intermediate from an all‐carbon 1,3‐dipole to an oxo‐1,5‐dipole. Enantioenriched seven‐membered lactones were produced with good reaction efficiencies and selectivities (23 examples, 52–92 % yields with up to 99:1 er and 12.5:1 dr). In addition, computational investigations were performed to rationalize the observed high chemo‐ and periselectivities. [ABSTRACT FROM AUTHOR]

Chiral catalysts tolerating photochemical reactions are in great demand for the vast development of visible‐light‐induced asymmetric synthesis. Now, chiral octahedral complexes based on earth‐abundant metal and chiral N4 ligands are reported. One well‐defined chiral CoII‐complex is shown to be an efficient catalyst in the visible‐light‐induced conjugated addition of enones by alkyl and acyl radicals, providing synthetically valued chiral ketones and 1,4‐dicarbonyls in 47–>99 % yields with up to 97:3 e.r. [ABSTRACT FROM AUTHOR]

The first example of a catalytic asymmetric formal [4+1] annulation reaction between sulfur ylides and in situ generated ortho-quinone methides (o-QMs) is reported in this work. A C2-symmetric chiral urea was identified to be the best H bonding catalyst, affording a wide range of chiral 2,3-dihydrobenzofurans in high yields and moderate enantioselectivities [70-98 % yields, up to 89:11 e.r. (enantiomeric ratio)]. [ABSTRACT FROM AUTHOR]

A catalytic asymmetric [3+2] cycloaddition reaction of chiral palladium-containing N1-1,3-dipoles with methyleneindolinones has been successfully developed. The reaction allows an efficient construction of 3,3′-pyrrolinyl spirooxindoles with high yields and excellent stereoselectivities (up to 93 % yield, 19:1 d.r. and >99 % ee). A synthetic application of this methodology is demonstrated and a stereocontrol mechanism is proposed. [ABSTRACT FROM AUTHOR]

A new hybrid P,S ligand was exploited by combining a chiral β-amino sulfide and a simple diphenyl phosphite. The resultant ligand performs extremely well in a palladium-catalyzed asymmetric decarboxylative [4+2] cycloaddition reaction, thus generating multiple contiguous stereocenters and a chiral quaternary center. By doing so, a straightforward route to highly functionalized tetrahydroquinolines was developed with yields of up to 99 %, as well as 98 % ee and greater than 95:5 d.r. Moreover, mechanistic insights into this transformation and the possible stereocontrol are discussed. [ABSTRACT FROM AUTHOR]

A new ring for your indole: An unprecedented copper‐catalyzed enantioselective Friedel–Crafts alkylation/N‐hemiacetalization cascade reaction with indoles and β,γ‐unsaturated α‐ketoesters is reported. This mild strategy provides new access to various synthetically and biologically important 2,3‐dihydro‐1H‐pyrrolo[1,2‐a]indoles in a highly enantioselective manner. [ABSTRACT FROM AUTHOR]

New players in town: In situ generated transition‐metal‐containing carbonyl ylides are a unique class of reagents which have found wide applications in catalytic asymmetric cascade reactions. Recent advances in reaction design are likely to lead to more novel developments with these reactive species. [ABSTRACT FROM AUTHOR]

Abstract: Optically active α-substituted phenyloxyacetyloxy and aroyloxy phosphonates have been synthesized via catalytic asymmetric hydrogenation of the corresponding prochiral α,β-unsaturated phosphonates using Rh(I)/(R,R)-Me-DuPhos as the catalyst in methanol at 18°C. The asymmetric hydrogenation reaction exhibits excellent enantioselectivity with enantiomeric excesses from 91 to 96%. [Copyright &y& Elsevier]