Photochemical Organocatalytic Synthesis of Thioethers from Aryl Chlorides and Alcohols

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(5), P. 2907 - 2912

Published: Jan. 24, 2024

Thioethers, often found in pharmaceuticals and natural compounds, typically involve metal cross-coupling reactions, high temperatures, the use of disagreeable thiols for their synthesis. Here we present a straightforward, thiol-free organocatalytic protocol that uses mild conditions to stitch together inexpensive alcohols aryl chlorides, yielding diverse array alkyl thioethers. Central this approach was discovery tetramethylthiourea can serve as simple sulfur source upon intercepting photochemically generated radicals. To form radicals, used readily available indole thiolate organocatalyst that, when excited with 405 nm light, gained strongly reducing power, enabling activation unreactive chlorides via single-electron transfer. Radical trapping by thiourea, followed an alcohol attack polar path, resulted formation thioether products.

Language: Английский

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C(sp²)–S cross-coupling reactions with nickel, visible light, and mesoporous graphitic carbon nitride

Green Chemistry, Journal Year: 2024, Volume and Issue: 26(10), P. 5845 - 5851

Published: Jan. 1, 2024

Operationally simple photo-nickel C(sp 2 )–S cross-coupling with a reusable heterogeneous photocatalyst.

Language: Английский

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Brønsted Acid-Facilitated Thioetherification Cross-Coupling Reactions with Nickel and Visible Light

ACS Catalysis, Journal Year: 2025, Volume and Issue: 15(3), P. 1467 - 1476

Published: Jan. 9, 2025

Transition metal-catalyzed cross-coupling reactions are essential in modern organic synthesis, facilitating the rapid creation of complex molecular structures. Traditionally, these rely heavily on conventional bases, with only a few exceptions reported. Recently, we developed adaptive dynamic homogeneous catalysis (AD-HoC), method that enables C(sp2)–S cross-couplings without needing traditional ligands, or additives. Given growing demand for protocols compatible acidic conditions cross-couplings, revisited AD-HoC to pioneer acid-facilitated transition thioetherification. Our swift synthesis thioethers using nickel and visible light, substoichiometric amount Brønsted acid acting as an enabler. NMR kinetic studies indicate absence acid, system displays induction period characteristic autocatalysis. Introducing simple additive eliminates this significantly accelerates reaction. Moreover, protocol has been successfully scaled gram-level continuous flow technology, achieving productivities over 100 g per hour commercially available lab-scale photoreactor. This highlights method's robustness scalability, making it powerful tool large-scale applications.

Language: Английский

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Nickel-embedded three-in-one pyridyl-quinoline-linked covalent organic framework photocatalysts for universal C(sp2) cross-coupling reactions

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: May 21, 2025

Metallaphotocatalysis, integrating interlocked photocatalytic cycles and transition-metal catalysis, harmonizes the ground state excited reactivities, enabling cross-couplings under mild conditions expanding scope of accessible transformations. However, homogeneous dual metallaphotocatalysts often suffer from limitations such as low catalyst stability, high metal loading, challenges in recycling. In this study, we engineered a class nickel-incorporated pyridyl-quinoline-linked covalent organic frameworks (Ni-PQCOFs) serving robust efficient heterogeneous metallaphotocatalysts. These Ni-PQCOFs facilitate universal visible-light-driven C(sp2)-carbon heteroatom (S, N, O, B, P, Se, Cl) bond formations across broad range aromatic halides nucleophiles, while maintaining loading (1-2 mol%). The Ni-PQCOFs, featuring fully conjugated tunable pyridyl-quinoline (PQ) motifs, exhibit exceptional (photo)chemical broadened absorption wavelength range, enhanced redox capability. Remarkably, these COF-based exhibited significantly catalytic efficiency compared to their counterparts. versatility practicality system extend diverse synthetic applications, including late-stage functionalization complex molecules, sequential functionalizations, decagram-scale synthesis assisted by an in-house-built high-speed circulation flow system. Moreover, micrometer-sized Ni-PQCOF could be recycled over 10 times through direct filtration with minimal activity loss negligible leaching. All advantages establish versatile, effective, sustainable for cross-coupling reactions.

Language: Английский

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Cross-Coupling Reactions with Nickel, Visible Light, and tert-Butylamine as a Bifunctional Additive

ACS Catalysis, Journal Year: 2024, Volume and Issue: 15(2), P. 817 - 827

Published: Dec. 27, 2024

Transition metal catalysis is crucial for the synthesis of complex molecules, with ligands and bases playing a pivotal role in optimizing cross-coupling reactions. Despite advancements ligand design base selection, achieving effective synergy between these components remains challenging. We present here general approach to nickel-catalyzed photoredox reactions employing tert-butylamine as cost-effective bifunctional additive, acting ligand. This method proves C-O C-N bond-forming diverse array nucleophiles, including phenols, aliphatic alcohols, anilines, sulfonamides, sulfoximines, imines. Notably, protocol demonstrates significant applicability biomolecule derivatization facilitates sequential one-pot functionalizations. Spectroscopic investigations revealed robustness dynamic catalytic system, while elucidation structure-reactivity relationships demonstrated how computed molecular properties both nucleophile electrophile correlated reaction performance, providing foundation outcome prediction.

Language: Английский

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Developing Ni and Pd precatalysts for demanding cross-coupling reactions

Advances in inorganic chemistry, Journal Year: 2024, Volume and Issue: unknown, P. 285 - 316

Published: Jan. 1, 2024

Language: Английский

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