Nickel‐Catalyzed Inter‐ and Intramolecular Aryl Thioether Metathesis by Reversible Arylation

Angewandte Chemie International Edition, Год журнала: 2019, Номер 59(5), С. 2110 - 2114

Опубликована: Дек. 12, 2019

Abstract A nickel‐catalyzed aryl thioether metathesis has been developed to access high‐value thioethers. 1,2‐Bis(dicyclohexylphosphino)ethane (dcype) is essential promote this highly functional‐group‐tolerant reaction. Furthermore, synthetically challenging macrocycles could be obtained in good yield an unusual example of ring‐closing that does not involve alkene bonds. In‐depth organometallic studies support a reversible Ni 0 /Ni II pathway product formation. Overall, work only provides more sustainable alternative previous catalytic systems based on Pd, but also presents new applications and mechanistic information are relevant the further development application single‐bond reactions.

Язык: Английский

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Recent advances in nickel-catalyzed C–C and C–N bond formation via HA and ADC reactions

Organic & Biomolecular Chemistry, Год журнала: 2021, Номер 19(19), С. 4213 - 4227

Опубликована: Янв. 1, 2021

In this review article, recent advances in nickel-catalyzed hydrogen auto-transfer (HA) and acceptorless dehydrogenative coupling (ADC) reactions for the construction of C–C C–N bonds have been discussed.

Язык: Английский

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Catalytic Amination of Phenols with Amines

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(3), С. 1144 - 1151

Опубликована: Янв. 11, 2022

Given the wide prevalence and ready availability of both phenols amines, aniline synthesis through direct coupling between these starting materials would be extremely attractive. Herein, we describe a rhodium-catalyzed amination phenols, which provides concise access to diverse anilines, with water as sole byproduct. The arenophilic rhodium catalyst facilitates inherently difficult keto–enol tautomerization by means π-coordination, allowing for subsequent dehydrative condensation amines. We demonstrate generality this redox-neutral catalysis carrying out reactions large array various electronic properties variety primary secondary Several examples late-stage functionalization structurally complex bioactive molecules, including pharmaceuticals, further illustrate potential broad utility method.

Язык: Английский

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Structure–Reactivity Relationships of Buchwald-Type Phosphines in Nickel-Catalyzed Cross-Couplings

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(42), С. 19635 - 19648

Опубликована: Окт. 17, 2022

The dialkyl-ortho-biaryl class of phosphines, commonly known as Buchwald-type ligands, are among the most important phosphines in Pd-catalyzed cross-coupling. These ligands have also been successfully applied to several synthetically valuable Ni-catalyzed cross-coupling methodologies and, demonstrated this work, top performing Suzuki Miyaura Coupling (SMC) and C-N coupling reactions, even outperforming employed bisphosphines like dppf many circumstances. However, little is about their structure-reactivity relationships (SRRs) with Ni, limited examples well-defined, catalytically relevant Ni complexes exist. In we report analysis phosphine SRRs four representative reactions. Our study was guided by data-driven classification analysis, which together mechanistic organometallic studies structurally characterized Ni(0), Ni(I), Ni(II) allowed us rationalize reactivity patterns catalysis. Overall, expect that will serve a platform for further exploration ligand organonickel chemistry well development new methodologies.

Язык: Английский

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Collaboration as a Key to Advance Capabilities for Earth-Abundant Metal Catalysis

Organic Process Research & Development, Год журнала: 2023, Номер 27(7), С. 1160 - 1184

Опубликована: Март 20, 2023

Earth-abundant metal (EAM) catalysis can have profound impact in the pharmaceutical industry terms of sustainability and cost improvements from replacing precious metals like palladium as well harnessing differential reactivity first-row that allows for novel transformations to enable more efficient routes clinical candidates. The strategy building these capabilities within process group at Bristol Myers Squibb is described herein, with general plan a reaction screening platform, demonstrating scalability, increasing mechanistic understanding catalyst activation. development catalytic utilizing nickel, cobalt, iron while highlighting importance collaboration internal external groups advance EAM our portfolio. challenges benefits working transition metals, including metrics implementation catalysis, such cost, mass intensity, commercial availability catalysts ligands, are discussed.

Язык: Английский

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Dual Nickel(II)/Mechanoredox Catalysis: Mechanical‐Force‐Driven Aryl‐Amination Reactions Using Ball Milling and Piezoelectric Materials

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(42)

Опубликована: Авг. 28, 2023

Abstract The combination of a nickel(II) catalyst and mechanoredox under ball‐milling conditions promotes mechanical‐force‐driven C−N cross‐coupling reactions. In this nickel(II)/mechanoredox cocatalyst system, the modulation oxidation state nickel center, induced by piezoelectricity, is used to facilitate highly efficient aryl‐amination reaction, which characterized broad substrate scope, an inexpensive catalysts (NiBr 2 BaTiO 3 ), short reaction times, almost negligible quantity solvents. Moreover, can be readily up‐scaled multi‐gram scale, all synthetic operations carried out atmospheric without need for complicated setups. Furthermore, force‐induced system suitable excitation‐energy‐accepting molecules poorly soluble polyaromatic substrates that are incompatible with solution‐based nickel(II)/photoredox cocatalysts.

Язык: Английский

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Visible-Light Mediated Reaction of Indole with Aryl Halides Using Porphyrin Photocatalyst: A Feasible Technique to Afford N-Functionalized Indoles

Catalysis Letters, Год журнала: 2024, Номер 154(8), С. 4176 - 4200

Опубликована: Март 11, 2024

Язык: Английский

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Effect of 6,6′-Substituents on Bipyridine-Ligated Ni Catalysts for Cross-Electrophile Coupling

ACS Catalysis, Год журнала: 2024, Номер 14(9), С. 6897 - 6914

Опубликована: Апрель 19, 2024

A family of 4,4′-tBu2-2,2′-bipyridine (tBubpy) ligands with substituents in either the 6-position, 4,4′-tBu2-6-Me-bpy (tBubpyMe), or 6 and 6′-positions, 4,4′-tBu2-6,6′-R2-bpy (tBubpyR2; R = Me, iPr, sBu, Ph, Mes), was synthesized. These were used to prepare Ni complexes 0, I, II oxidation states. We observed that 6′-positions tBubpy ligand impact properties complexes. For example, bulkier 6,6′-positions better stabilized (tBubpyR2)NiICl species resulted a cleaner reduction from (tBubpyR2)NiIICl2. However, hindered prevented coordination tBubpyR2 Ni0(cod)2. In addition, by using type (tBubpyMe)NiCl2 (tBubpyR2)NiCl2 as precatalysts for different XEC reactions, we demonstrated 6,6′-substituents lead major differences catalytic performance. Specifically, while (tBubpyMe)NiIICl2 is one most active catalysts reported date can facilitate reactions at room temperature, lower turnover frequencies containing ligands. detailed study on intermediates (tBubpy)Ni(Ar)I (tBubpyMe2)Ni(Ar)I revealed several factors likely contributed activity. whereas are low spin relatively stable, high-spin less stable. Furthermore, captures primary benzylic alkyl radicals more slowly than (tBubpy)Ni(Ar)I, consistent activity former catalysis. Our findings will assist design tailor-made Ni-catalyzed transformations.

Язык: Английский

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MAdPHOS, a P-Stereogenic Aminodiphosphane Ligand with Adamantyl Groups: Synthesis, NH/PH Tautomerism, and Rhodium and Nickel Complexes

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 28, 2025

A novel chiral ligand, named MAdPHOS, bearing a P-stereogenic phosphane and diadamantyl linked by NH bridge has been synthesized. This bulky, C1-symmetric, PNP ligand prepared from enantiopure tert-butylmethyl aminophosphane was obtained as crystalline solid. The NH/PH tautomerism, air-stability, σ-donor capacity of MAdPHOS have assessed herein. free prepared, showing much higher stability, in the solid form, than its tert-butyl analogue MaxPHOS. Both rhodium nickel COD complexes prepared. Rh-MAdPHOS complex shown outstanding enantioselectivities asymmetric hydrogenation enamides.

Язык: Английский

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Direct C(sp²)−H Amination to Synthesize Primary 3‐aminoquinoxalin‐2(1H)‐ones under Simple and Mild Conditions

Advanced Synthesis & Catalysis, Год журнала: 2019, Номер 361(7), С. 1662 - 1667

Опубликована: Янв. 25, 2019

Abstract A convenient C−H amination of quinoxalin‐2‐ones has been developed. This transformation provides concise access to 3‐aminoquinoxalin‐2(1 H )‐ones with a broad tolerance functional groups, utilizing TMSN 3 as an amino source under simple and mild conditions. The target are important intermediates for the synthesis biologically active 3‐ N ‐substituted quinoxalin‐2‐one derivatives. magnified image

Язык: Английский

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