Borrowing Hydrogen for Organic Synthesis

ACS Central Science, Год журнала: 2021, Номер 7(4), С. 570 - 585

Опубликована: Март 25, 2021

Borrowing hydrogen is a process that used to diversify the synthetic utility of commodity alcohols. A catalyst first oxidizes an alcohol by removing form reactive carbonyl compound. This intermediate can undergo diverse range subsequent transformations before returns "borrowed" liberate product and regenerate catalyst. In this way, alcohols may be as alkylating agents whereby sole byproduct one-pot reaction water. recent decades, significant advances have been made in area, demonstrating many effective methods access valuable products. outlook highlights diversity metal biocatalysts are available for approach, well various performed, focusing on selection most advances. By succinctly describing conveying versatility borrowing chemistry, we anticipate its uptake will increase across wider scientific audience, expanding opportunities further development.

Язык: Английский

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Iron-Catalyzed α-Alkylation of Ketones with Secondary Alcohols: Access to β-Disubstituted Carbonyl Compounds

Organic Letters, Год журнала: 2020, Номер 22(5), С. 2064 - 2069

Опубликована: Фев. 24, 2020

An iron-catalyzed borrowing hydrogen strategy has been applied in the synthesis of β-branched carbonyl compounds. Various secondary benzylic and aliphatic alcohols have used as alkylating reagents under mild reaction conditions. The ketones isolated good to excellent yield. Deuterium labeling experiments provide evidence that alcohol is hydride source this no reversible step or hydrogen/deuterium scrambling takes place during process.

Язык: Английский

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Asymmetric Guerbet Reaction to Access Chiral Alcohols

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(28), С. 11408 - 11415

Опубликована: Апрель 15, 2020

The first example of an asymmetric Guerbet reaction has been developed. Using commercially available, classic Noyori RuII -diamine-diphosphine catalysts, well-known in hydrogenation, racemic secondary alcohols are shown to couple with primary the presence a base, affording new chiral enantiomeric ratios up 99:1. Requiring no reducing agents, protocol provides easy, alternative route for synthesis alcohols. Mechanistic studies reveal that proceeds via Ru-catalyzed hydrogen autotransfer process concert base-promoted allylic alcohol isomerization.

Язык: Английский

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The Deuterated “Magic Methyl” Group: A Guide to Site‐Selective Trideuteromethyl Incorporation and Labeling by Using CD₃Reagents

Chemistry - A European Journal, Год журнала: 2021, Номер 27(46), С. 11751 - 11772

Опубликована: Июнь 2, 2021

Abstract In the field of medicinal chemistry, precise installation a trideuteromethyl group is gaining ever‐increasing attention. Site‐selective incorporation deuterated “magic methyl” can provide profound pharmacological benefits and be considered an important tool for drug optimization development. This review provides structured overview, according to trideuteromethylation reagent, currently established methods site‐selective carbon atoms. addition CD 3 , selective introduction 2 H CDH groups also considered. For all methods, corresponding mechanism scope are discussed whenever reported. As such, this starting point synthetic chemists further advance methodologies. At same time, aims guide chemists, offering them available C−CD formation strategies preparation new or modified drugs.

Язык: Английский

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Multi-Functionality of Methanol in Sustainable Catalysis: Beyond Methanol Economy

ACS Catalysis, Год журнала: 2023, Номер 13(22), С. 15013 - 15053

Опубликована: Ноя. 6, 2023

Methanol is a fundamental feedstock and widely used in the chemical petroleum industries. It can serve as C1 source to make variety of C–C C–N bond formation dehydrogenative coupling products, which have important applications natural products drug discovery. A high hydrogen content (12.5 wt%) methanol makes it an effective H2 donor for transfer hydrogenation various reducible functional groups. plethora transition metal-based processes been developed using methanol. Notably, recent review articles focused on aspect However, more updated that examines challenges both C1-source H2-source organic transformations contributing concept economy has not presented yet. This Review summarizes (homogeneous, heterogeneous, photo-) catalyst system C-, N-, O-methylation ketones, alcohols, amides, nitriles, heterocyclic compounds, sulfones, amines, sulfonamides direct N-methylation nitro compounds under borrowing strategy N-formylation amines acceptorless dehydrogenation source. also covers insights into reaction mechanisms role carefully selected ligands metal catalysis activation incorporation -CD3, methylation molecules. Moreover, describes groups such aldehydes, alkynes, with detail.

Язык: Английский

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Recent advances on cross-coupling of alcohols via borrowing hydrogen catalysis

Chemical Communications, Год журнала: 2024, Номер 60(30), С. 4002 - 4014

Опубликована: Янв. 1, 2024

This article highlights the recent advances and significance of β-alkylation reactions towards synthesis higher order alcohols.

Язык: Английский

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Sustainable and Selective Alkylation of Deactivated Secondary Alcohols to Ketones by Non‐bifunctional Pincer N‐heterocyclic Carbene Manganese

ChemSusChem, Год журнала: 2020, Номер 13(10), С. 2557 - 2563

Опубликована: Март 31, 2020

Abstract A sustainable and green route to access diverse functionalized ketones via dehydrogenative–dehydrative cross‐coupling of primary secondary alcohols is demonstrated. This borrowing hydrogen approach employing a pincer N‐heterocyclic carbene Mn complex displays high activity selectivity. variety are well tolerant result in satisfactory isolated yields. Mechanistic studies suggest that this reaction proceeds direct outer‐sphere mechanism the dehydrogenation alcohol substrates plays vital role rate‐limiting step.

Язык: Английский

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Iron-Catalyzed Hydrogen Transfer Reduction of Nitroarenes with Alcohols: Synthesis of Imines and Aza Heterocycles

The Journal of Organic Chemistry, Год журнала: 2020, Номер 86(1), С. 1023 - 1036

Опубликована: Дек. 16, 2020

A straightforward and selective reduction of nitroarenes with various alcohols was efficiently developed using an iron catalyst via a hydrogen transfer methodology. This protocol led specifically to imines in 30–91% yields, good functional group tolerance. Noticeably, starting from o-nitroaniline derivatives, the presence alcohols, benzimidazoles can be obtained 64–72% yields when reaction performed additional oxidant, DDQ, quinoxalines were prepared 1,2-diols 28–96% yields. methodology, unprecedented at for imines, also provides sustainable alternative preparation benzimidazoles.

Язык: Английский

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Ru-Catalyzed Selective Catalytic Methylation and Methylenation Reaction Employing Methanol as the C1 Source

The Journal of Organic Chemistry, Год журнала: 2021, Номер 86(15), С. 10544 - 10554

Опубликована: Июль 15, 2021

Methanol can be employed as a green and sustainable methylating agent to form C–C C–N bonds via borrowing hydrogen (BH) methodology. Herein we explored the activity of acridine-derived SNS-Ru pincer for activation methanol apply it C1 building block in different reactions. Our catalytic system shows great success toward β-C(sp3)-methylation reaction 2-phenylethanols provide good excellent yields methylated products. We investigated mechanistic details, kinetic progress, temperature-dependent product distribution, which revealed slow steady generation situ formed aldehyde, is key factor get higher yield β-methylated product. To establish environmental benefit this reaction, chemistry metrics are calculated. Furthermore, dimerization 2-naphthol methylene linkage formation N-methylation amine also described study, offers wide range substrate scope with yield.

Язык: Английский

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Recent advances in sustainable organic transformations using methanol: expanding the scope of hydrogen-borrowing catalysis

Organic Chemistry Frontiers, Год журнала: 2021, Номер 8(24), С. 7077 - 7096

Опубликована: Янв. 1, 2021

Recent progress relating to sustainable approaches using methanol as a C1-alkylating agent for C–Me and N–Me bond formation is discussed.

Язык: Английский

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