Selective deoxygenation of biomass-derived carbonyl compounds on Zn via electrochemical Clemmensen reduction

Nature Catalysis, Journal Year: 2024, Volume and Issue: 7(1), P. 43 - 54

Published: Jan. 4, 2024

Language: Английский

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Practical and General Alcohol Deoxygenation Protocol

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(18)

Published: Feb. 25, 2023

Herein, we describe a practical protocol for the removal of alcohol functional groups through reductive cleavage their benzoate ester analogs. This transformation requires strong single electron transfer (SET) reductant and means to accelerate slow fragmentation following substrate reduction. To accomplish this, developed photocatalytic system that generates potent from formate salts alongside Brønsted or Lewis acids promote reduced intermediate. deoxygenation procedure is effective across structurally electronically diverse alcohols enables variety difficult net transformations. no precautions exclude air moisture remains efficient on multigram scale. Finally, can be adapted one-pot benzoylation-deoxygenation sequence enable direct deletion. Mechanistic studies validate role acidic additives key C(sp

Language: Английский

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Selective hydrodeoxygenation of α, β-unsaturated carbonyl compounds to alkenes

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

Published: March 9, 2024

Abstract Achieving selective hydrodeoxygenation of α, β-unsaturated carbonyl groups to alkenes poses a substantial challenge due the presence multiple functional groups. In this study, we develop ZnNC-X catalyst (X represents calcination temperature) that incorporates both Lewis acidic-basic sites and Zn-N x address challenge. Among variants, ZnNC-900 exhibits impressive selectivity for in compounds, achieving up 94.8% selectivity. Through comprehensive mechanism investigations characterization, identify as responsible hydrogenation C=O bonds, while facilitate subsequent step. Furthermore, displays broad applicability across diverse range unsaturated compounds. These findings not only offer valuable insights into design effective catalysts controlling alkene but also extend scope sustainable transformations synthetic chemistry.

Language: Английский

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Improved Friction and Wear Performance Utilized with Aminoguanidine-Based Ionic Liquid Over Wide Temperature Range for Reciprocating Frictional Contact Surface

Tribology Letters, Journal Year: 2025, Volume and Issue: 73(2)

Published: Feb. 17, 2025

Language: Английский

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Nickel-Catalyzed Exhaustive Hydrodefluorination of Perfluoroalkyl Arenes

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(20), P. 11449 - 11456

Published: May 4, 2023

Perfluoroalkyl compounds are persistent environmental pollutants due to their strong C(sp3)-F bonds. Hydrodefluorination has emerged as a potential alternative disposal method for perfluoroalkyl compounds. Although the transformation of trifluoromethyl arenes into corresponding methyl been studied by several research groups, hydrodefluorination reactions longer chains remain rare. Herein, we report exhaustive pentafluoroethyl and longer-chain analogues using molecular nickel catalysis. Despite cleavage multiple bonds, reaction already proceeds upon gentle heating (60 °C). A mechanistic investigation indicated that via benzylic followed homobenzylic ones. We reveal roles Ni catalyst, which include C-F bond cleavage, promotion HF elimination, hydrosilylation.

Language: Английский

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Deoxygenative Silylation of C(sp³)–O Bonds with Hydrosilane by Cooperative Catalysis of Gold Nanoparticles and Solid Acids

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(10), P. 6787 - 6794

Published: May 3, 2023

Efficient deoxygenative silylation of C(sp3)–O bonds with hydrosilanes by supported Au catalysts is described. Gold nanoparticles on TiO2 enabled various to be used as sources silyl groups in C–Si cross-coupling reactions. A variety alkyl acetates and propargyl carbonates participated the Au-catalyzed reactions furnish corresponding allenylsilanes high yields. In addition, Au/TiO2 was also effective for ring-opening cyclic ethers. detailed mechanistic investigation corroborated that title reaction involves formation radical intermediates, cooperation single-electron transfer Lewis acid sites at surface metal oxides responsible unusual reactivity specific C(sp3)–Si bond formation.

Language: Английский

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Deuterium- and Electron-Shuttling Catalysis for Deoxygenative Deuteration of Alcohols

Organic Letters, Journal Year: 2023, Volume and Issue: 25(35), P. 6571 - 6576

Published: Aug. 30, 2023

A practical and precise method for visible-light-promoted deoxygenative deuteration of common aliphatic alcohols using D2O as the deuterium source is reported. Upon intermediacy xanthate anions, a variety primary, secondary, tertiary can be facilely transformed into deuterioalkanes with excellent D-incorporation at predicted sites. The deoxygenation sequence catalyzed by in situ formed deuterated 2-mercaptopyridine, which plays dual roles atom transfer catalyst an electron shuttle well.

Language: Английский

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Cobalt-Catalyzed Reductive Deoxygenation of Aldehydes, Ketones, Alcohols, and Ethers to Alkanes

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(6), P. 4249 - 4264

Published: March 5, 2024

The development of simple and general catalytic methods using abundant base metal catalysts for the deoxygenation organic compounds valorization biomass chemical synthesis remains a formidable challenge. Cobalt pincer-catalyzed reductive aldehydes, ketones, alcohols, ethers to their corresponding alkanes is reported. Biomass-derived were deoxygenated methylarenes. This system employs diethylsilane as reductant requires substoichiometric amount base. Investigations revealed initial deprotonation amine arm on catalyst, catalysis begins with Si–H activation silane facilitated by amine-amide metal–ligand cooperation. In situ-formed Co–H species carry out hydrosilylation carbonyl compounds, dehydrosilylation hydrosilanolysis ethers, resulting in common arylmethylsilyl or alkylsilyl ether intermediates. Further, reaction leads formation siloxane oligomers. DFT study reveals closely lying singlet–triplet electronic states different intermediates facilitating mechanism spin surfaces, verified through located minimum energy crossing points (MECPs). case alcohol, another low pathway where amide pincer, instead hydride, can abstract hydroxy proton enable

Language: Английский

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Selective Biocatalytic Defunctionalization of Raw Materials

ChemSusChem, Journal Year: 2022, Volume and Issue: 15(9)

Published: April 7, 2022

Biobased raw materials, such as carbohydrates, amino acids, nucleotides, or lipids contain valuable functional groups with oxygen and nitrogen atoms. An abundance of many the same type, primary secondary hydroxy in however, limits synthetic usefulness if similar reactivities cannot be differentiated. Therefore, selective defunctionalization highly functionalized biobased starting materials to differentially compounds can provide a sustainable access chiral synthons, even case products fewer groups. Selective reactions, without affecting other are fundamental interest for biocatalytic reactions. Controlled defunctionalizations attractive obtaining platform chemicals building blocks. The removal groups, an important feature natural metabolic pathways, also utilized systemic strategy metabolite synthesis.

Language: Английский

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Ti-Catalyzed Dehydroxylation of Tertiary Alcohols

Organic Letters, Journal Year: 2022, Volume and Issue: 24(46), P. 8459 - 8464

Published: Nov. 10, 2022

Herein we report a Ti-catalyzed direct dehydroxylation of tertiary aliphatic alcohols under mild reaction conditions, forging Barton-type deoxygenation products. This protocol tolerates wide range functional groups, including primary alkyl chloride and carbonyl groups. It allows for selective in diols the formation deuterated products with moderate deuterium incorporation. The efficient modification several drugs natural (or their derivatives) highlights synthetic utility this method.

Language: Английский

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