Enantioselective Au(I)/Au(III) Redox Catalysis Enabled by Chiral (P,N)-Ligands

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(16), P. 7089 - 7095

Published: April 18, 2022

Presented herein is the first report of enantioselective Au(I)/Au(III) redox catalysis, enabled by a newly designed hemilabile chiral (P,N)-ligand (ChetPhos). The potential this concept has been demonstrated development 1,2-oxyarylation and 1,2-aminoarylation alkenes which provided direct access to medicinally relevant 3-oxy- 3-aminochromans (up 88% yield 99% ee). DFT studies were carried out unravel enantiodetermining step, revealed that stronger trans influence phosphorus allows selective positioning substrate in C2-symmetric environment present around nitrogen, imparting high level enantioselectivity.

Language: Английский

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Transition-metal-catalyzed C–H bond alkylation using olefins: recent advances and mechanistic aspects

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(17), P. 7358 - 7426

Published: Jan. 1, 2022

Transition metal catalysis has contributed immensely to C-C bond formation reactions over the last few decades, and alkylation is no exception. The superiority of such methodologies traditional evident from minimal reaction steps, shorter times, atom economy while also allowing control regio- stereo-selectivity. In particular, hydrocarbonation alkenes grabbed increased attention due its fundamental ability effectively selectively synthesise a wide range industrially pharmaceutically relevant moieties. This review attempts provide scientific viewpoint systematic analysis recent developments in transition-metal-catalyzed various C-H bonds using simple activated olefins. key features mechanistic studies involved these transformations are described briefly.

Language: Английский

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Gold-Catalyzed Heck Reaction

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(16), P. 8810 - 8816

Published: April 16, 2023

Herein, we report a gold-catalyzed Heck reaction facilitated by the ligand-enabled Au(I)/Au(III) redox catalysis. The elementary organometallic steps such as migratory insertion and β-hydride elimination have been realized in catalytic fashion for first time gold chemistry. present methodology not only overcomes limitations of previously known transition metal-catalyzed reactions requirement specialized substrates formation mixture regioisomeric products result undesirable chain-walking process but also offers complementary regioselectivity compared to other metal

Language: Английский

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Atomically Dispersed Co-N/C Catalyst for Divergent Synthesis of Nitrogen-Containing Compounds from Alkenes

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(7), P. 4142 - 4149

Published: Feb. 8, 2023

Alkene functionalization with a single-atom catalyst (SAC) which merges homogeneous and heterogeneous catalysis is fascinating route to obtain high-value-added molecules. However, C–N bond formation of alkene SAC still unexplored. Herein, bimetal-organic framework-derived Co–N/C an atomically dispersed cobalt center reported show good activity chemoselective aziridination/oxyamination reactions from hydroxylamine, late-stage complex alkenes diversified synthetic transformations the aziridine product further expand utility this method. Moreover, system proceeds without external oxidants exhibits mild, atom-economic, recyclable characters. Detailed spectroscopic characterizations mechanistic studies revealed structure catalytic possible intermediates involved in mechanism cycle.

Language: Английский

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Electrochemical gold-catalysed biocompatible C(sp2)–C(sp) coupling

Nature Synthesis, Journal Year: 2023, Volume and Issue: 2(4), P. 338 - 347

Published: Jan. 12, 2023

Language: Английский

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Consolidation of the Oxidant‐Free Au(I)/Au(III) Catalysis Enabled by the Hemilabile Ligand Strategy

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(27)

Published: April 30, 2024

Abstract In this minireview we survey the challenges and strategies in gold redox catalysis. Gold's reluctance to oxidative addition reactions due its high potential limits applicability. Initial attempts overcome problem focused on use of sacrificial external oxidants stoichiometric amounts bring Au(I) compounds Au(III) reactive species. Recently, innovative approaches employing hemilabile ligands, which are capable coordinating stabilizing square‐planar intermediates, thus facilitating steps enabling oxidant‐free Notable examples include (P^N) bidendate MeDalphos ligand achieve various cross‐coupling via Au(I)/Au(III). Importantly, ligand‐enabled catalysis allows merging with π‐activation, such as oxy‐ aminoarylation alkenols alkenamines using organohalides, expanding gold‘s versatility C−C C‐heteroatom bond formations unprecedented cyclizations. Moreover, recent advancements enantioselective chiral ligands also surveyed. Strikingly, versatile bidentate (C^N) competitors have appeared recently, by designing scaffolds where phosphine groups substituted N‐heterocyclic or mesoionic carbenes. Overall, these highlight evolving landscape tremendous a broad scope transformations.

Language: Английский

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Cu-Catalyzed Diastereo- and Enantioselective Synthesis of Borylated Cyclopropanes with Three Contiguous Stereocenters

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 17, 2025

Direct synthesis of enantioenriched scaffolds with multiple adjacent stereocenters remains an important yet challenging task. Herein, we describe a highly diastereo- and enantioselective Cu-catalyzed alkylboration cyclopropenes, less reactive alkyl iodides as electrophiles, for the efficient tetra-substituted borylated cyclopropanes bearing three consecutive stereocenters. This protocol features mild conditions, broad substrate scope, good functional group tolerance, affording array chiral in to high yields excellent enantioselectivities. Detailed mechanistic experiments kinetic studies were conducted elucidate reaction pathway rate-determining step reaction. DFT calculations revealed that π···π stacking interaction between phenyl groups on phosphorus ligand, along smaller distortion CuL-Bpin part, contributed The synthetic utility was showcased by facile some valuable centers.

Language: Английский

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Intermolecular 1,2-Difunctionalization of Alkenes Enabled by Fluoroamide-Directed Remote Benzyl C(sp³)–H Functionalization

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 144(1), P. 339 - 348

Published: Dec. 22, 2021

A copper-catalyzed remote benzylic C-H functionalization strategy enabling 1,2-difunctionalization of alkenes with 2-methylbenzeneamides and nucleophiles, including alcohols, indoles, pyrroles, the intrinsic amino groups, is reported, which characterized by its redox-neutral conditions, exquisite site-selectivity, broad substrate scope, wide utilizations late-stage modifying bioactive molecules. This reaction proceeds through nitrogen-centered radical generation, hydrogen atom transfer, addition across alkenes, single-electron oxidation, carbocation electrophilic course cascades. While using external nucleophiles manipulates three-component alkene alkylalkoxylation alkyl-heteroarylation to access dialkyl ethers, 3-alkylindoles, 3-alkylpyrroles, omitting results in two-component alkylamidation ([5+2] annulation) benzo-[f][1,2]thiazepine 1,1-dioxides.

Language: Английский

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Chiral Hemilabile P,N‐Ligand‐Assisted Gold Redox Catalysis for Enantioselective Alkene Aminoarylation

Chemistry - A European Journal, Journal Year: 2022, Volume and Issue: 28(34)

Published: April 14, 2022

Enantioselective, intermolecular alkene arylamination was achieved through gold redox catalysis. Screening of ligands revealed chiral P,N as the optimal choice, giving aminoarylation with good yields (up to 80 %) and excellent stereoselectivity 99 : 1 er). As first example enantioselective catalysis, this work confirmed feasibility applying a ligand at gold(I) stage, stereodetermining step (SDS) gold(III) intermediate, thus opening up new way conduct catalysis stereochemistry control.

Language: Английский

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Au(I)/Au(III) Catalytic Allylation Involving π-Allyl Au(III) Complexes

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(2), P. 993 - 1003

Published: Jan. 3, 2022

A (MeDalphos)AuCl complex was found to efficiently catalyze the cross-coupling of indoles and allyl acetates/alcohols. The reaction tolerates many functional groups selectively affords branched C3-allylated products from both α- γ-substituted substrates. It takes advantage hemilabile character P∧N ligand. C(sp2)–C(sp3) coupling operates via a Au(I)/Au(III) redox cycle involves dicationic π-allyl Au(III) as key intermediate. In this case, moiety adopts an asymmetric σ + π-coordination mode, substantiated by NMR spectroscopy density theory (DFT) calculations.

Language: Английский

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