Stereodivergent Synthesis of Tertiary Fluoride-Tethered Allenes via Copper and Palladium Dual Catalysis

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(19), P. 7285 - 7291

Published: May 10, 2021

Herein we describe a protocol for the unprecedented stereodivergent synthesis of tertiary fluoride-tethered allenes bearing stereogenic center and axis via Cu/Pd synergistic catalysis. A broad scope conjugated enynes are coupled with various α-fluoroesters in high yields diastereoselectivities generally >99% ee. In addition, four stereoisomers allene products ensure precise access to corresponding fluorinated hydrofurans novel axial-to-central chirality transfer process.

Language: Английский

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Recent Advances in the Catalytic Synthesis of Arylsulfonyl Compounds

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(7), P. 4169 - 4204

Published: March 19, 2021

Arylsulfonyl compounds are among the most important in pharmaceutical and medicinal chemistry. Hence, a wide variety of sulfonylation methods have been reported recently. This review summarizes arylsulfonylation methodologies developed last 5 years includes two major categories. The first entails direct second multicomponent arylsulfonylation. In arylsulfonylation, arylsulfonyl reagents react with C–H activated compounds, alkynes, alkenes through coupling or addition reactions. reactions, arylation various substrates sulfur dioxide surrogates, such as DABSO, Na2S2O5, K2S2O5. hydrazides, aryl boronic acids, silanes, halides widely employed that surrogates to generate an source, ensuing reactions proceed via pathways analogous those

Language: Английский

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Catalytic Asymmetric Hydroalkoxylation and Formal Hydration and Hydroaminoxylation of Conjugated Dienes

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(7), P. 3915 - 3925

Published: Feb. 10, 2023

The straightforward construction of stereogenic centers bearing unprotected functional groups, as in nature, has been a persistent pursuit synthetic chemistry. Abundant applications free enantioenriched allyl alcohol and hydroxylamine motifs have made the asymmetric hydration hydroaminoxylation conjugated dienes from water hydroxylamine, respectively, intriguing efficient routes that have, however, unachievable thus far. A fundamental challenge is failure to realize transition-metal-catalyzed enantioselective C–O bond constructions via hydrofunctionalization dienes. Here, we perform comprehensive study toward stereoselective formal by synthesizing set new P,N-ligands identifying an aryl-derived oxime surrogate for both hydroxylamine. Asymmetric hydroalkoxylation with also elucidated. Furthermore, versatile derivatizations following provide indirect but concise hydrophenoxylation, hydrofluoroalkoxylation, hydrocarboxylation unreported Finally, ligand-to-ligand hydrogen transfer process proposed based on results preliminary mechanistic experiments.

Language: Английский

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Single-Electron Oxidation-Initiated Enantioselective Hydrosulfonylation of Olefins Enabled by Photoenzymatic Catalysis

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(4), P. 2748 - 2756

Published: Jan. 12, 2024

Controlling the enantioselectivity of hydrogen atom transfer (HAT) reactions has been a long-standing synthetic challenge. While recent advances on photoenzymatic catalysis have demonstrated great potential non-natural photoenzymes, all transformations are initiated by single-electron reduction substrate, with only one notable exception. Herein, we report an oxidation-initiated enantioselective hydrosulfonylation olefins using novel mutant gluconobacter ene-reductase (GluER-W100F-W342F). Compared to known systems, our approach does not rely formation electron donor–acceptor complex between substrates and enzyme cofactor simplifies reaction system obviating addition regeneration mixture. More importantly, GluER variant exhibits high reactivity broad substrate scope. Mechanistic studies support proposed mechanism reveal that tyrosine-mediated HAT process is involved.

Language: Английский

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Photoinduced, Palladium-Catalyzed Enantioselective 1,2-Alkylsulfonylation of 1,3-Dienes

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(5), P. 3725 - 3732

Published: Feb. 21, 2024

The chiral allylic sulfonylated group is a unique structural motif embedded in range of natural products and pharmaceuticals. Notably, the synthesis structurally diverse derivatives via alkylsulfonylation 1,3-dienes remains underexplored because its inherent challenges stereocontrol regioselectivity. Herein, photoinduced, palladium-catalyzed enantioselective 1,2-alkylsulfonylation conjugated described. A wide variety alkyl bromides, 1,3-dienes, sodium sulfinates could be facilely coupled to generate value-added with high enantioselectivity. Finally, utility this difunctionalization protocol was demonstrated pharmaceutical analogue synthesis.

Language: Английский

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Enantioselective Hydrothiolation: Diverging Cyclopropenes through Ligand Control

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(16), P. 6176 - 6184

Published: April 15, 2021

In this article, we advance Rh-catalyzed hydrothiolation through the divergent reactivity of cyclopropenes. Cyclopropenes undergo to provide cyclopropyl sulfides or allylic sulfides. The choice bisphosphine ligand dictates whether pathway involves ring-retention ring-opening. Mechanistic studies reveal origin for switchable selectivity. Our results suggest two pathways share a common cyclopropyl-Rh(III) intermediate. Electron-rich Josiphos ligands promote direct reductive elimination from intermediate afford in high enantio- and diastereoselectivities. Alternatively, atropisomeric (such as DTBM-BINAP) enable ring-opening generate with regiocontrol.

Language: Английский

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Orthogonal Regulation of Nucleophilic and Electrophilic Sites in Pd‐Catalyzed Regiodivergent Couplings between Indazoles and Isoprene

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(15), P. 8321 - 8328

Published: Jan. 19, 2021

Abstract Depending on the reactant property and reaction mechanism, one major regioisomer can be favored in a that involves multiple active sites. Herein, an orthogonal regulation of nucleophilic electrophilic sites regiodivergent hydroamination isoprene with indazoles is demonstrated. Under Pd‐hydride catalysis, 1,2‐ or 4,3‐insertion pathway respect to could controlled by choice ligands. In terms indazoles, occurs at either N 1 ‐ 2 ‐position governed acid co‐catalysts. Preliminary experimental studies have been performed rationalize mechanism regioselectivity. This study not only contributes practical tool for selective functionalization isoprene, but also provides guide manipulate regioselectivity ‐functionalization indazoles.

Language: Английский

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Palladium-Catalyzed Asymmetric Sequential Hydroamination of 1,3-Enynes: Enantioselective Syntheses of Chiral Imidazolidinones

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(25), P. 11364 - 11376

Published: June 10, 2022

Pd-catalyzed sequential hydroamination of readily available 1,3-enynes is reported. The redox-neutral process provides an efficient route to synthesize a broad scope imidazolidinones, thiadiazolidines, and imidazolidines. Asymmetric generates series synthetically valuable, enantioenriched imidazolidinones. Mechanistic studies revealed that the transformation occurred via intermolecular enyne pathway give allene intermediate. Subsequent intramolecular intermediate proceeded under Curtin-Hammett principle provide imidazolidinone products.

Language: Английский

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Enantioselective Hydroalkoxylation of 1,3-Dienes via Ni-Catalysis

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(7), P. 3909 - 3914

Published: Feb. 10, 2023

As an advance in hydrofunctionalization, we herein report that alcohols add to 1,3-dienes with high regio- and enantioselectivity. Using Ni-DuPhos, access enantioenriched allylic ethers. Through the choice of solvent-free conditions, control reversibility C–O bond formation. This work showcases a rare example methanol as reagent asymmetric synthesis.

Language: Английский

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Copper‐Catalyzed Remote Enantioselective Sulfonylation of Yne‐Allylic Esters with Sodium Sulfinates

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(52)

Published: Nov. 13, 2023

Impressive progress has been made in the copper-catalyzed asymmetric propargylic substitution (APS) reaction, but its use remote yne-allylic remains a challenging topic. Herein, we report first enantioselective sulfonylation of esters with sodium sulfinates. The reaction is assumed to occur via copper-vinylvinylidene species as key reactive intermediate. readily available starting materials, mild conditions, and excellent regio-, enantio- stereoselectivity, well broad substrate scope (>70 examples), show practicality attractiveness this method.

Language: Английский

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