Recent advances in gold-complex and chiral organocatalyst cooperative catalysis for asymmetric alkyne functionalization

Chinese Chemical Letters, Journal Year: 2022, Volume and Issue: 33(12), P. 4969 - 4979

Published: April 23, 2022

Language: Английский

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Gold-catalyzed multicomponent reactions

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(9), P. 2359 - 2384

Published: Jan. 1, 2023

Multicomponent reactions (MCRs) have emerged as an important branch in organic synthesis for the creation of complex molecular structures. This review is focused on gold-catalyzed MCRs with a special emphasis recent developments.

Language: Английский

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Hexafluoroisopropanol (HFIP) as a Multifunctional Agent in Gold-Catalyzed Cycloisomerizations and Sequential Transformations

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(13), P. 8845 - 8860

Published: June 20, 2023

Despite the unique position of gold catalysis in contemporary organic synthesis, this area research is notorious for requiring activators and/or additives that enable by generating cationic forms catalysts. Cycloisomerization reactions occupy a significant portion gold-catalyzed reaction space, while they represent diverse family are frequently utilized synthesis. Herein, hexafluoroisopropanol (HFIP) shown to be uniquely simple tool cycloisomerizations, rendering use external obsolete and leading highly active catalytic systems with ppm levels catalyst loading certain cases. HFIP assumes dual role as solvent an activator, operating via dynamic activation Au–Cl bond through hydrogen bonding, which initiates cycle. This special mode can efficient scalable cyclization propargylamides ynoic acids [AuCl(L)] complexes. A thorough screening ancillary ligands counter anions has been performed, establishing methodology alternative elaborate ligand/catalyst design activators. Additionally, concept applied C–C bond-forming cycloisomerization 2H-chromenes sequential or one-pot transformations activated ketoesters, functionalized N-heterocyclic carbene (NHC) precursor salt, compound bearing bioactive indole core, among others. Importantly, mechanistic investigations, including "snapshot" species interest solid state, we were able unambiguously detect key H-bonding interaction between catalyst, shedding light on intermolecular enables catalysis. In cases examined herein, not only excellent but also potent activator valuable synthetic handle when incorporated into functional groups products.

Language: Английский

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Asymmetric gold catalysis enabled by specially designed ligands

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(6), P. 1858 - 1895

Published: Jan. 1, 2024

This review is planned to provide a comprehensive overview of the progress made in design and development chiral ligands for asymmetric gold catalysis.

Language: Английский

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Catalytic Enantioselective Protonation of Gold Enolates Enabled by Cooperative Gold(I) Catalysis

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(6), P. 3598 - 3602

Published: Jan. 31, 2024

Enantioselective protonation is a versatile approach to the construction of tertiary α-stereocenters, which are common structural motifs in various natural products and biologically relevant compounds. Herein we report mild access these chiral centers using cooperative gold(I) catalysis. From cyclic ketone enol carbonates, this asymmetric catalysis provides highly enantioselective ketones featuring an α center, including challenging 2-methylsuberone. In combination with gold-catalyzed formation cyclopentadienyl carbonates one-pot, two-step process, chemistry enables expedient synthetically α′-chiral cyclopentenones excellent enantiomeric excesses from easily accessible enynyl carbonate substrates.

Language: Английский

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Gold-catalyzed enantioselective functionalization of indoles

Organic & Biomolecular Chemistry, Journal Year: 2020, Volume and Issue: 18(31), P. 6006 - 6017

Published: Jan. 1, 2020

This review documents the potential of enantioselective gold catalysis for functionalization indoles.

Language: Английский

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New‐Generation Ligand Design for the Gold‐Catalyzed Asymmetric Activation of Alkynes

ChemPlusChem, Journal Year: 2021, Volume and Issue: 86(9), P. 1283 - 1296

Published: July 12, 2021

Abstract Gold(I) catalysts are ideal for the activation of alkynes under very mild conditions. However, unlike allenes or alkenes, triple bond cannot be prochiral. In addition, linear coordination displayed by gold(I) complexes places chiral ligand far away from substrate resulting in an inefficient transfer information. This poses a significant challenge achievement high enantiocontrol gold(I)‐catalyzed reactions alkynes. Although considerable progress on enantioselective transformations has recently been achieved, asymmetric non‐prochiral alkyne‐containing small molecules still represents great challenge. Herein we summarize recent advances intra‐ and intermolecular involving alkynes, discussing new designs that lie at basis these developments. We also focus mode action catalysts, their possible limitations towards next‐generation more efficient designs. Finally, square planar gold(III) complexes, which offer alternative to discussed.

Language: Английский

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Enantioselective Alkoxycyclization of 1,6‐Enynes with Gold(I)‐Cavitands: Total Synthesis of Mafaicheenamine C

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(17), P. 9339 - 9344

Published: Feb. 12, 2021

Chiral gold(I)-cavitand complexes have been developed for the enantioselective alkoxycyclization of 1,6-enynes. This cyclization has applied first total synthesis carbazole alkaloid (+)-mafaicheenamine C and its enantiomer, establishing configuration as R. The cavity effect was also evaluated in cycloisomerization dienynes. A combination experiments theoretical studies demonstrates that gold(I) forces enynes to adopt constrained conformations, which results high observed regio- stereoselectivities.

Language: Английский

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Enantioselective Au(I)-Catalyzed Multicomponent Annulations via Tethered Counterion-Directed Catalysis

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(7), P. 4046 - 4053

Published: March 16, 2022

Gold(I) complexes of a chiral phosphoric acid-functionalized phosphine the CPA-Phos series enable enantioselective multicomponent reactions between aldehydes, hydroxylamines and cyclic yne-enones, leading to 3,4-dihydro-1H-furo[3,4-d][1,2]oxazines. This represents rare example highly reaction in gold(I) catalysis. The proceed at low catalyst loading provide high yields, total diastereoselectivity, enantiomeric excesses up 99%. Silver-free conditions can be applied. method has very broad scope as it applies both aliphatic aromatic aldehydes hydroxylamines, variety yne-enone-derived oximes. DFT calculations complement this study enlighten reactivity issues mechanistic pathways.

Language: Английский

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Hydrogen bonding-enabled gold catalysis: ligand effects in gold-catalyzed cycloisomerizations in hexafluoroisopropanol (HFIP)

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(61), P. 8516 - 8519

Published: Jan. 1, 2022

Gold catalysis has witnessed immense evolution in recent years, yet it still requires the use of activators to render common [AuCl(L)] complexes catalytically active. Herein, H-bonding donor properties hexafluoroisopropanol (HFIP) are utilized for Au-Cl bond activation and ancillary ligand counteranion effects on cycloisomerization reactions showcased HFIP as solvent.

Language: Английский

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