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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Selective Catalytic Synthesis of α-Alkylated Ketones and β-Disubstituted Ketones via Acceptorless Dehydrogenative Cross-Coupling of Alcohols

Organic Letters, Год журнала: 2021, Номер 23(3), С. 869 - 875

Опубликована: Янв. 21, 2021

Herein, a phosphine-free pincer ruthenium(III) catalyzed β-alkylation of secondary alcohols with primary to α-alkylated ketones and two different β-branched are reported. Notably, this transformation is environmentally benign atom efficient H2O H2 gas as the only byproducts. The protocol extended gram-scale reaction for functionalization complex vitamin E cholesterol derivatives.

Язык: Английский

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Recent Advances for Alkylation of Ketones and Secondary Alcohols Using Alcohols in Homogeneous Catalysis

Advanced Synthesis & Catalysis, Год журнала: 2022, Номер 364(18), С. 3100 - 3121

Опубликована: Июль 4, 2022

Abstract The alkylation of ketones or secondary alcohols using as alkylating agents via hydrogen borrowing strategy presents a powerful method for the synthesis ɑ‐alkylated ketones. In this review, we summarize progress catalyzed by Ir, Pd, Rh, Ru, Mn, Fe, Co, Ni, and Cu catalysts α‐alkylation with cross‐coupling from 2017 to 2021. A wide range (aromatic aliphatic ketones) (benzylic primary alcohols, aromatic alkenyl diols) are well tolerated. Furthermore, also discuss current challenges propose perspectives on coming development in filed. objective present review is give an overview recent advances β‐alkylation alcohols. Finally, hope that will inspirations magnified image

Язык: Английский

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Acid-Promoted Multicomponent Reaction To Synthesize 4-Phosphorylated 4H-Chromenes

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(12), С. 8531 - 8536

Опубликована: Июнь 5, 2024

An effective multicomponent reaction for the synthesis of 4-phosphorylated 4H-chromenes via a tandem phosphorylation/alkylation/cyclization/dehydration sequence with water as only byproduct was developed. Extensive mechanistic investigations involving in situ NMR experiments, time control and HRMS experiment allowed us to elucidate order each subreaction arrive at complete understanding underlying mechanism this reaction. Mechanistic data confirm that begins phospha-aldol-elimination, followed by addition ketone enolate, intermolecular alkylation, intramolecular cyclization, dehydration under acidic conditions.

Язык: Английский

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A Proton‐Responsive Pyridyl(benzamide)‐Functionalized NHC Ligand on Ir Complex for Alkylation of Ketones and Secondary Alcohols

Chemistry - A European Journal, Год журнала: 2021, Номер 27(41), С. 10737 - 10748

Опубликована: Май 17, 2021

Abstract A Cp*Ir(III) complex ( 1 ) of a newly designed ligand L featuring proton‐responsive pyridyl(benzamide) appended on N ‐ heterocyclic carbene (NHC) has been synthesized. The molecular structure reveals dearomatized form the ligand. protonation with HBF 4 in tetrahydrofuran gives corresponding aromatized [Cp*Ir(L H)Cl]BF 2 ). Both compounds are characterized spectroscopically and by X‐ray crystallography. acid is examined H NMR UV‐vis spectra. character exploited for catalyzing α ‐alkylation ketones β secondary alcohols using primary as alkylating agents through hydrogen‐borrowing methodology. Compound an effective catalyst these reactions exhibits superior activity comparison to structurally similar iridium )Cl]PF 6 3 lacking pendant amide moiety. catalytic alkylation wide substrate scope, low base loadings, short reaction time. efficacy also demonstrated syntheses quinoline lactone derivatives via acceptorless dehydrogenation, selective two steroids, pregnenolone testosterone. Detailed mechanistic investigations DFT calculations substantiate role process.

Язык: Английский

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Catalytic Formal Conjugate Addition: Direct Synthesis of δ-Hydroxynitriles from Nitriles and Allylic Alcohols

ACS Catalysis, Год журнала: 2022, Номер 12(4), С. 2191 - 2204

Опубликована: Янв. 28, 2022

Alcohols and nitrile functionalities have widespread applications in biochemical chemical synthesis. Catalytic transformations involving C–C bond formation relying on unsaturated coupling partners create important pathways for processes synthetic, material, medicinal chemistry. The discovery of a simple selective nitriles with allylic alcohols catalyzed by ruthenium pincer complex is described, which tolerates reactive functional groups such as carbamate, sulfonate, olefin, cyano, trifluoromethyl-substituted benzyl nitriles. Homo also provided 1,4-addition products following the isomerization double bonds. Mechanistic studies supported that initially undergo oxidation catalyst to α,β-unsaturated carbonyl compounds followed 1,4-conjugate addition base subsequent catalytic reduction functionality, leading δ-hydroxynitrile products. cycle this tandem process established density theory studies. Remarkably, anipamil drug successfully synthesized using protocol. utility synthesis biologically active molecules their further functionalization are demonstrated.

Язык: Английский

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Biogenic synthesis of δ‐MnO₂ nanoparticles: A sustainable approach for C‐alkylation and quinoline synthesis via acceptorless dehydrogenation and borrowing hydrogen reactions

Applied Organometallic Chemistry, Год журнала: 2023, Номер 37(7)

Опубликована: Апрель 26, 2023

The sustainable and environmentally benign biogenic synthesis of manganese‐oxide nanoparticles (MnO 2 NPs) in a single crystalline δ ‐phase its subsequent synthetic utility have been described. synthesized ‐MnO NPs were characterized using scanning electron microscopy (SEM), energy dispersive X‐ray (EDX), diffraction (XRD) analysis techniques. detailed envisages the reduction Mn(VII) to Mn(IV) was facilitated by various phytochemicals present aq. mango leaves extract, avoiding use external ligand source. perceived delta ( ) monoclinic phase, wherein spherical agglomerated morphology displayed with particle size <5 nm. Further, newly developed showcased for alpha‐keto‐alkylation quinoline via hydrogen autotransfer acceptorless dehydrogenative coupling strategy. Moreover, series control experiments, mechanistic elucidation, catalyst recyclability, dye removal study demonstrated.

Язык: Английский

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CrCl₂-catalyzed α-alkylation of carbonyl compounds via a borrowing hydrogen approach

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(7), С. 1955 - 1962

Опубликована: Янв. 1, 2024

A new and efficient catalytic system for sustainable α-alkylation of carbonyl compounds with alcohols via a borrowing hydrogen strategy is presented.

Язык: Английский

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Progressive study on ruthenium catalysis for de(hydrogenative) alkylation and alkenylation using alcohols as a sustainable source

Organic & Biomolecular Chemistry, Год журнала: 2022, Номер 20(41), С. 7998 - 8030

Опубликована: Янв. 1, 2022

This review focuses on the Ru-catalyzed de(hydrogenative) formation of C–C and CC bonds. The comparative reactivity different Ru-complexes to gain selectivity in product is presented, together with brief mechanistic insights.

Язык: Английский

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Recent advances in C/N-alkylation with alcohols through hydride transfer strategies

Organic & Biomolecular Chemistry, Год журнала: 2022, Номер 20(39), С. 7713 - 7745

Опубликована: Янв. 1, 2022

Recent advances in C/N alkylation using alcohols as alkylating reagents via hydrogen-shuttle methodologies: Borrowing Hydrogen, Acceptorless Dehydrogenative Coupling, and Base-mediated Hydride Transfer.

Язык: Английский

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