A decarbonylative approach to alkylnickel intermediates and C(sp ³ )-C(sp ³ ) bond formation

Science, Journal Year: 2024, Volume and Issue: 385(6715), P. 1331 - 1337

Published: Sept. 19, 2024

The myriad nickel-catalyzed cross-coupling reactions rely on the formation of an organonickel intermediate, but limitations in forming monoalkylnickel species have limited options for C(sp 3 ) cross-coupling. monoalkylnickel(II) from abundant carboxylic acid esters would be valuable, derivatives are primarily decarboxylated to form alkyl radicals that lack correct reactivity. In this work, we disclose a facile oxidative addition and decarbonylation sequence forms intermediates through nonradical process. key ligand, bis(4-methylpyrazole)pyridine, accelerates decarbonylation, stabilizes alkylnickel(II) destabilizes off-cycle nickel(0) carbonyl species. utility new reactivity )-C(sp bond is demonstrated reaction challenging by purely radical methods—the selective primary with iodides.

Language: Английский

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Decarboxylative stereoretentive C–N coupling by harnessing aminating reagent

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: May 6, 2024

Abstract In recent decades, strategies involving transition-metal catalyzed carbon-carbon or carbon-heteroatom bond coupling have emerged as potent synthetic tools for constructing intricate molecular architectures. Among these, decarboxylative carbon-nitrogen formation using abundant carboxylic acids their derivatives has garnered notable attention accessing alkyl- arylamines, one of key pharmacophores. While several amination methods been developed, the involvement a common carboradical intermediate currently poses challenges in achieving stereospecific transformation toward chiral alkylamines. Herein, we present base-mediated, stereoretentive amidation by harnessing 1,4,2-dioxazol-5-one reactive and robust amidating reagent under transition-metal-free ambient conditions, encompassing all types primary, secondary tertiary acids, thereby providing access to important pharmacophore, α-chiral amines. This method exhibits high functional group tolerance, convenient scalability, ease applicability 15 N-isotope labeling, thus accentuating its utilities. Experimental computational mechanistic investigations reveal sequence elementary steps: i) nucleophilic addition carboxylate dioxazolone, ii) rearrangement form dicarbonyl N-hydroxy intermediate, iii) conversion hydroxamate, followed Lossen-type rearrangement, finally, iv) reaction situ generated isocyanate with leading C–N manner.

Language: Английский

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Visible-Light-Induced Esterification of Carboxylic Acids with Arylsulfonium Salts

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 26, 2025

A photoinduced copper-mediated acyloxylation of arylthianthrenium or arylphenoxathiinium salts with either aliphatic aromatic carboxylic acids is described for the convenient synthesis O-aryl esters. The reaction has shown obvious advantages, such as high efficiency, good functional group tolerance, excellent chemoselectivity, and capacity esterification complex drug molecules, offering a practical synthetic route to multifunctionalized sterically congested esters, which are potentially useful in development new prodrugs twin drugs.

Language: Английский

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Enantioselective Total Syntheses of Vallesamidine and Schizozygane Alkaloids

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

Published: Jan. 27, 2025

A general streamlined strategy for the enantioselective total syntheses of schizozygane family natural products and related alkaloid vallesamidine is described. Specifically, a catalytic enantioconvergent cross-coupling sets quaternary stereogenic center in pluripotent intermediate adorned with an olefin three orthogonal carboxylate groups, upon which modularity synthesis relies. late-stage oxidative lactamization alkyne instrumental first-generation alkaloids. In second-generation approach, novel application van Leusen reaction generation lactams pivotal to accessing alkaloids from common intermediate. The strategies outlined here are expected enable detailed biological investigations as well facilitate access provide solutions modification bioactive

Language: Английский

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Lewis and Brønsted Acids Synergy in Photocatalytic Aerobic Alcohol Oxidations

Angewandte Chemie International Edition, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 31, 2025

Photocatalytic chemical transformations for green organic synthesis has attracted much interest. However, their development is greatly hampered by the lack of sufficient reactive sites on photocatalyst surface adsorption and activation substrate molecules. Herein, we demonstrate that introduction well-defined Lewis Brønsted acid coexisting TiO2 (SO4 2-/N-TiO2) creates abundant active photoredox reactions. The electron-deficient supply coordinatively unsaturated to adsorb molecular oxygen, are liable donate protons form hydrogen bonds with OH groups alcohols like benzyl alcohol (BA). These coexistent result in a strong synergistic effect photocatalytic aerobic oxidation BA. For example, conversion BA benzaldehyde was found be 88.6 %, being higher than those pristine (14.7 %), N-doped (N-TiO2, 24.6 sulfated 2-/ TiO2, 35.4 even sum. apparent quantum efficiency (AQE) determined 58.1 % at 365 nm 12.9 420 over SO4 2-/N-TiO2. This strategy create effective acids catalyst surfaces enables us apply it other semiconducting transformations.

Language: Английский

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