State-of-the-Art Advances in Enantioselective Transition-Metal-Mediated Reactions of Silacyclobutanes

Synthesis, Journal Year: 2022, Volume and Issue: 54(24), P. 5400 - 5408

Published: Aug. 23, 2022

Abstract Studies on the enantioselective transformation of silacyclobutanes (SCBs) have become an emerging topic in recent decade, due to feature high ring strain, and manageable Si–C bond cleavage formation. This short review summarizes remarkable achievements asymmetric transition-metal-mediated reaction benzosilacyclobutanes, resulting carbon- or silicon-stereogenic organosilanes with functional substituents. 1 Introduction2 Asymmetric Transition-Metal-Catalyzed Ring Expansion Reaction3 Ring-Opening Reaction4 Conclusion Outlook

Language: Английский

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Pd/Ming-Phos-Catalyzed Asymmetric Three-Component Arylsilylation of N-Sulfonylhydrazones: Enantioselective Synthesis of gem-Diarylmethine Silanes

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(34), P. 15468 - 15474

Published: Aug. 22, 2022

A Pd-catalyzed enantioselective three-component reaction of N-sulfonylhydrazones, aryl bromides, and silylboronic esters is developed, enabling the synthesis chiral gem-diarylmethine silanes in high enantioselectivity with use a newly identified Ming-Phos. Compared N-tosyl, more easily decomposed N-mesitylsulfonyl suitable as masking group electron-rich hydrazone to improve efficiency. The features broad scope concerning both coupling partners, enantioselectivity, mild conditions. ready access enantiomers utility this catalytic method are also presented.

Language: Английский

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Dirhodium: carbene transformations and beyond

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(11), P. 2849 - 2878

Published: Jan. 1, 2023

Dirhodium-catalyzed transformations, not limited to carbene and nitrene transfer reactions, are reviewed, including cycloisomerization, hetero-Diels–Alder (HDA) ene arylation, radical oxidation reactions C–H activation, etc .

Language: Английский

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Chiral organophosphates as ligands in asymmetric metal catalysis

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(12), P. 3080 - 3109

Published: Jan. 1, 2023

Chiral phosphates have successfully been used as ligands in asymmetric metal-catalysis. This Minireview discusses the most recent examples, including main-group catalysis, transition-metal catalysis and by rare-earth metals.

Language: Английский

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Regio- and enantioselective CuH-catalyzed 1,2- and 1,4-hydrosilylation of 1,3-enynes

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Aug. 19, 2023

We report a copper-catalyzed ligand-controlled selective 1,2- and 1,4-hydrosilylation of 1,3-enynes, which furnishes enantiomerically enriched propargyl- 1,2-allenylsilane products in high yields with excellent enantioselectivities (up to 99% ee). This reaction proceeds under mild conditions, shows broad substrate scope for both 1,3-enynes trihydrosilanes, displays regioselectivities. Mechanistic studies based on deuterium-labeling reactions density functional theory (DFT) calculations suggest that allenylcopper is the dominant reactive intermediate it undergoes metathesis silanes via four-membered or six-membered transition state, depending nature ligand. The weak interactions between ligands reacting partners are found be key controlling factor observed regioselectivity switch. origin enantiocontrol also revealed by level DLPNO-CCSD(T) calculations.

Language: Английский

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Synthesis of Chiral Endocyclic Allenes and Alkynes via Pd-Catalyzed Asymmetric Higher-Order Dipolar Cycloaddition

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 18, 2024

A Pd-catalyzed asymmetric higher-order dipolar cycloaddition between allenyl carbonates and azadienes is achieved by exploiting novel alkylidene-π-allyl-Pd dipoles. This research provides a modular platform for the synthesis of challenging chiral endocyclic allenes bearing medium-sized heterocyclic motif centrally stereocenter in good yields with high enantio- diastereoselectivities (29 examples, up to 97% yield, 97:3 er >19:1 dr). Experimental computational studies elucidate possible reaction mechanism observed stereochemical results. Based on mechanistic understanding, new π-propargyl-Pd dipole was designed further extend success higher order strategy 10-membered alkynes from propargyl (13 98% yield 94.5:5.5 er).

Language: Английский

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Enantioselective synthesis of inherently chiral 9-benzylidene-9H-tribenzo[a,c,e][7]annulene and its application as a ligand platform

Chem Catalysis, Journal Year: 2024, Volume and Issue: 4(3), P. 100904 - 100904

Published: Jan. 31, 2024

Language: Английский

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Regioselective Ni-Catalyzed reductive alkylsilylation of acrylonitrile with unactivated alkyl bromides and chlorosilanes

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Nov. 19, 2022

Abstract Transition-metal catalyzed carbosilylation of alkenes using carbon electrophiles and silylmetal (-B, -Zn) reagents as the nucleophiles offers a powerful strategy for synthesizing organosilicones, by incorporating silyl groups across on C-C double bonds in one step. However, to best our knowledge, study silylative difunctionalization based remains underdeveloped. Herein, we present an example alkylation activated olefins with unactivated alkyl bromides chlorosilanes under nickel catalysis. The main feature this protocol is employing more easily accessible substrates including primary, secondary tertiary bromides, well various without pre-generated organometallics. A wide range alkylsilanes diverse structures can be efficiently assembled single step, highlighting good functionality tolerance approach. Furthermore, successful functionalization bioactive molecules synthetic applications method demonstrate its practicability.

Language: Английский

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Catalytic Asymmetric Synthesis of Chiral Propargylic Boron Compounds through B–H Bond Insertion Reactions

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(17), P. 10654 - 10660

Published: Aug. 16, 2022

Chiral propargylic boron compounds have a diverse array of potential applications. Although numbers highly enantioselective methodologies for the synthesis other organoboron are well established, chiral remains unknown. Herein, we report catalytic method construction by means dirhodium-catalyzed B–H bond insertion reactions using aryl sulfonylhydrazones as carbene precursors. This enables straightforward wide range stable in yields up to 99% with enantioselectivities 97% ee. The operationally simple features broad substrate scope, good functional group tolerance, and mild reaction conditions. prepared this study inaccessible known methods exhibit high utility because they could be efficiently transformed into allenyl borates, triazole borane compounds, homopropargylic alcohols enantiomeric fidelity. Our work expands library reactions, increases variety that can synthesized, provides preliminary information about possible transformations thus laying foundation application these compounds.

Language: Английский

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Ag-Catalyzed Insertion of Alkynyl Carbenes into C–C Bonds of β-Ketocarbonyls: A Formal C(sp²) Insertion

Organic Letters, Journal Year: 2022, Volume and Issue: 24(2), P. 631 - 636

Published: Jan. 5, 2022

Here we report a silver-catalyzed alkynyl carbene insertion into β-ketocarbonyls using N-nosylhydrazones as precursors, which provides access to trisubstituted allenyl ketones. This reaction represents the first example of an C-C σ bond, affording products homologated with sp2 carbon center. The are useful substrates for further transformations. Experimental investigations and theoretical calculations suggest proceeds through stepwise enol cyclopropanation/retro-aldol pathway.

Language: Английский

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