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Abstract
Nitroxides, also known as nitroxyl radicals, are long-lived or stable radicals with the general structure R1R2N-O•. The spin distribution over the nitroxide N and O atoms contributes to the thermodynamic stability of these radicals. The presence of bulky N-substituents R1 and R2 prevents nitroxide radical dimerization, ensuring their kinetic stability. Despite their reactivity toward various transient C radicals, some nitroxides can be easily stored under air at room temperature. Furthermore, nitroxides can be oxidized to oxoammonium salts (R1R2N═O+) or reduced to anions (R1R2N-O-), enabling them to act as valuable oxidants or reductants depending on their oxidation state. Therefore, they exhibit interesting reactivity across all three oxidation states. Due to these fascinating properties, nitroxides find extensive applications in diverse fields such as biochemistry, medicinal chemistry, materials science, and organic synthesis. This review focuses on the versatile applications of nitroxides in organic synthesis. For their use in other important fields, we will refer to several review articles. The introductory part provides a brief overview of the history of nitroxide chemistry. Subsequently, the key methods for preparing nitroxides are discussed, followed by an examination of their structural diversity and physical properties. The main portion of this review is dedicated to oxidation reactions, wherein parent nitroxides or their corresponding oxoammonium salts serve as active species. It will be demonstrated that various functional groups (such as alcohols, amines, enolates, and alkanes among others) can be efficiently oxidized. These oxidations can be carried out using nitroxides as catalysts in combination with various stoichiometric terminal oxidants. By reducing nitroxides to their corresponding anions, they become effective reducing reagents with intriguing applications in organic synthesis. Nitroxides possess the ability to selectively react with transient radicals, making them useful for terminating radical cascade reactions by forming alkoxyamines. Depending on their structure, alkoxyamines exhibit weak C-O bonds, allowing for the thermal generation of C radicals through reversible C-O bond cleavage. Such thermally generated C radicals can participate in various radical transformations, as discussed toward the end of this review. Furthermore, the application of this strategy in natural product synthesis will be presented.
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Affiliation(s)
- Dirk Leifert
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
| | - Armido Studer
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany
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Neshat A, Cheraghi M, Kucerakova M, Dusek M, Mobarakeh AM. A Cu(II) Complex Based on a Schiff Base Ligand Derived from Ortho-vanillin: Synthesis, DFT Analysis and Catalytic Activities. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.134545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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3
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Ying S, Huang X, Guo X, Yang S. The sequential C–H oxidation/asymmetric phosphonylation of primary alcohols to synthesize α-hydroxy phosphonates. GREEN SYNTHESIS AND CATALYSIS 2021. [DOI: 10.1016/j.gresc.2021.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
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Barma A, Bhattacharjee A, Roy P. Dinuclear Copper(II) Complexes with N,O Donor Ligands: Partial Ligand Hydrolysis and Alcohol Oxidation Catalysis. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100263] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Arpita Barma
- Department of Chemistry Jadavpur University Jadavpur Kolkata 700 032 India
| | | | - Partha Roy
- Department of Chemistry Jadavpur University Jadavpur Kolkata 700 032 India
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Choudhury P, Behera PK, Bisoyi T, Sahu SK, Sahu RR, Prusty SR, Stitgen A, Scanlon J, Kar M, Rout L. The dehydrogenative oxidation of aryl methanols using an oxygen bridged [Cu–O–Se] bimetallic catalyst. NEW J CHEM 2021. [DOI: 10.1039/d1nj00712b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein, we report a new protocol for the dehydrogenative oxidation of aryl methanols using the cheap and commercially available catalyst CuSeO3·2H2O.
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Affiliation(s)
| | | | - Tanmayee Bisoyi
- Department of Chemistry
- Berhampur University
- Odisha-760007
- India
| | | | - Rashmi Ranjan Sahu
- Department of Chemistry
- Berhampur University
- Odisha-760007
- India
- Department of Physics, IIT Patna
| | | | | | | | | | - Laxmidhar Rout
- Department of Chemistry
- Berhampur University
- Odisha-760007
- India
- Adjunct Faculty, School of Chemical Science, Indian Institute of Science Education and Research
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Razmara Z, Janczak J. Synthesis and crystal structure of a new heteronuclear complex of Fe(iii)-K designed to produce effective catalysts for CO hydrogenation. Dalton Trans 2020; 49:10498-10508. [PMID: 32691025 DOI: 10.1039/d0dt01230k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new paramagnetic heteronuclear complex formulated as [K3Fe(μ-ox)3(H2O)3]n (1), where ox2- is oxalate, has been synthesized under hydrothermal condition. The molecular structure of complex 1 was characterized by elemental analysis, Fourier-transform infrared spectroscopy (FT-IR) and single-crystal X-ray diffraction (SCXRD). The results of SC-XRD analysis revealed that complex 1 crystallizes in the centrosymmetric space group P21/c of a monoclinic system with cell dimension a = 7.7175 (4) Å, b = 19.8009 (7) Å, c = 10.2623 (5) Å, and β = 107.634 (5)° at 100 K. The thermal behavior of complex 1 was studied by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The magnetic behavior of complex 1 was studied at room temperature by a vibration sample magnetometer (VSM). Thermal decomposition of the silica and alumina supports of complex 1 at 650 °C resulted in the main catalysts, Fe2O3-K2O/SiO2 and Fe2O3-K2O/Al2O3. The catalytic activity of the main catalysts was evaluated for CO hydrogenation. For comparative purposes, the reference catalysts of Fe2O3-K2O/SiO2 and Fe2O3-K2O/Al2O3 were prepared by the impregnation method. The structure and composition of the catalysts were investigated by FT-IR spectroscopy, powder X-ray diffraction (PXRD), N2 adsorption-desorption analysis, scanning electron microscopy (SEM), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and energy dispersive X-ray analysis (EDX). We tested all catalysts for hydrogenation of CO at 5 bar of pressure in the temperature range of 593-673 K. It was found that the main catalysts have better CO conversion and selectivity to desired products, such as light olefins, than the reference catalysts.
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Affiliation(s)
- Zohreh Razmara
- Department of Chemistry, University of Zabol, P.O. Box 98613-35856, Zabol, Iran.
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Liu K, Zhang J, Huo S, Dong Q, Hao Z, Han Z, Lu GL, Lin J. Highly efficient oxidation of alcohols catalyzed by Ru(II) carbonyl complexes bearing salicylaldiminato ligands. Inorganica Chim Acta 2020. [DOI: 10.1016/j.ica.2019.119224] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Photochemical oxidation of alcohols: Simple derivatization strategy for their analysis by capillary electrophoresis. Food Chem 2019; 292:114-120. [DOI: 10.1016/j.foodchem.2019.04.043] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 01/31/2023]
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Yan X, Yue X, Liu K, Hao Z, Han Z, Lin J. Synthesis and Structures of Ruthenium Carbonyl Complexes Bearing Pyridine-Alkoxide Ligands and Their Catalytic Activity in Alcohol Oxidation. Front Chem 2019; 7:394. [PMID: 31214574 PMCID: PMC6558070 DOI: 10.3389/fchem.2019.00394] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 05/16/2019] [Indexed: 02/05/2023] Open
Abstract
Reaction of Ru3(CO)12 with two equiv of 6-bromopyridine alcohols 6-bromopyCHROH [(R = C6H5 (L1); R = 4-CH3C6H4 (L2); R = 4-OMeC6H4 (L3); R = 4-ClC6H4 (L4); (R = 4-CF3C6H4 (L5); R = 2-OMeC6H4 (L6); R = 2-CF3C6H4 (L7)] and 6-bromopyC(Me)2OH (L8) in refluxing xylene afforded novel trinuclear ruthenium complexes [6-bromopyCHRO]2Ru3(CO)8 (1a-1g) and [6-bromopyC(Me)2O]2Ru3(CO)8 (1h). These complexes were characterized by FT-IR and NMR spectroscopy as well as elemental analysis. The structures of all the complexes were further confirmed by X-ray crystallographic analysis. In the presence of tert-butyl hydroperoxide (TBHP) as the source of oxidant, complexes 1a-1h displayed high catalytic activities for oxidation of primary and secondary alcohols and most of oxidation reactions could be completed within 1 h at room temperature.
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Affiliation(s)
- Xinlong Yan
- Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang, China
| | - Xiaohui Yue
- Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang, China
| | - Kang Liu
- Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang, China
| | - Zhiqiang Hao
- Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang, China
| | - Zhangang Han
- Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang, China
| | - Jin Lin
- Hebei Key Laboratory of Organic Functional Molecules, College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang, China
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Abstract
The oxidation of alcohols to the corresponding carbonyl products is an important organic transformation and the products are used in a variety of applications. The development of catalytic methods for selective alcohol oxidation have garnered significant attention in an attempt to find a more sustainable method without any limitations. Copper, in combination with 2,2,6,6-tetramethyl-1-piperidine N-oxyl (TEMPO) and supported by organic ligands, have emerged as the most effective catalysts for selective alcohol oxidation and these catalyst systems are frequently compared to galactose oxidase (GOase). The efficiency of GOase has led to extensive research to mimic the active sites of these enzymes, leading to a variety of Cu/TEMPO· catalyst systems being reported over the years. The mechanistic pathway by which Cu/TEMPO· catalyst systems operate has been investigated by several research groups, which led to partially contradicting mechanistic description. Due to the disadvantages and limitations of employing TEMPO· as co-catalyst, alternative nitroxyl radicals or in situ formed radicals, as co-catalysts, have been successfully evaluated in alcohol oxidation. Herein we discuss the development and mechanistic elucidation of Cu/TEMPO· catalyst systems as biomimetic alcohol oxidation catalysts.
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Zhai D, Ma S. Copper catalysis for highly selective aerobic oxidation of alcohols to aldehydes/ketones. Org Chem Front 2019. [DOI: 10.1039/c9qo00740g] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A general and practical room temperature aerobic oxidation of different types of alcohols using Cu(NO3)2·3H2O and TEMPO or 4-HO-TEMPO as the catalysts forming aldehydes or ketones with an excellent selectivity has been developed.
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Affiliation(s)
- Di Zhai
- Research Center for Molecular Recognition and Synthesis
- Department of Chemistry
- Fudan University
- Shanghai 200433
- P. R. China
| | - Shengming Ma
- Research Center for Molecular Recognition and Synthesis
- Department of Chemistry
- Fudan University
- Shanghai 200433
- P. R. China
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Zong S, Liu K, Yue X, Hao Z, Ma Z, Han Z, Lu GL, Lin J. Ruthenium carbonyl complexes supported by pyridine-alkoxide ligands: synthesis, structure and catalytic oxidation of secondary alcohols. NEW J CHEM 2019. [DOI: 10.1039/c9nj03222c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Five novel trinuclear ruthenium carbonyl complexes were synthesized and their application in oxidation of secondary alcohols was also researched.
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Affiliation(s)
- Siqi Zong
- National Demonstration Center for Experimental Chemistry Education
- Hebei Key Laboratory of Organic Functional Molecules
- College of Chemistry & Material Science
- Hebei Normal University
- Shijiazhuang 050024
| | - Kang Liu
- National Demonstration Center for Experimental Chemistry Education
- Hebei Key Laboratory of Organic Functional Molecules
- College of Chemistry & Material Science
- Hebei Normal University
- Shijiazhuang 050024
| | - Xiaohui Yue
- National Demonstration Center for Experimental Chemistry Education
- Hebei Key Laboratory of Organic Functional Molecules
- College of Chemistry & Material Science
- Hebei Normal University
- Shijiazhuang 050024
| | - Zhiqiang Hao
- National Demonstration Center for Experimental Chemistry Education
- Hebei Key Laboratory of Organic Functional Molecules
- College of Chemistry & Material Science
- Hebei Normal University
- Shijiazhuang 050024
| | - Zhihong Ma
- School of Pharmacy
- Hebei Medical University
- Shijiazhuang 050017
- China
| | - Zhangang Han
- National Demonstration Center for Experimental Chemistry Education
- Hebei Key Laboratory of Organic Functional Molecules
- College of Chemistry & Material Science
- Hebei Normal University
- Shijiazhuang 050024
| | - Guo-Liang Lu
- Auckland Cancer Society Research Centre
- Faculty of Medical and Health Sciences
- The University of Auckland
- Auckland 1142
- New Zealand
| | - Jin Lin
- National Demonstration Center for Experimental Chemistry Education
- Hebei Key Laboratory of Organic Functional Molecules
- College of Chemistry & Material Science
- Hebei Normal University
- Shijiazhuang 050024
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13
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Synthesis, characterization and catalytic activities of rhenium carbonyl complexes bearing pyridine-alkoxide ligands. J Organomet Chem 2018. [DOI: 10.1016/j.jorganchem.2018.06.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Kataoka K, Wachi K, Jin X, Suzuki K, Sasano Y, Iwabuchi Y, Hasegawa JY, Mizuno N, Yamaguchi K. CuCl/TMEDA/nor-AZADO-catalyzed aerobic oxidative acylation of amides with alcohols to produce imides. Chem Sci 2018; 9:4756-4768. [PMID: 29910926 PMCID: PMC5982222 DOI: 10.1039/c8sc01410h] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/05/2018] [Indexed: 01/25/2023] Open
Abstract
Although aerobic oxidative acylation of amides with alcohols would be a good complement to classical synthetic methods for imides (e.g., acylation of amides with activated forms of carboxylic acids), to date, there have been no reports on oxidative acylation to produce imides. In this study, we successfully developed, for the first time, an efficient method for the synthesis of imides through aerobic oxidative acylation of amides with alcohols by employing a CuCl/TMEDA/nor-AZADO catalyst system (TMEDA = teramethylethylendiamine; nor-AZADO = 9-azanoradamantane N-oxyl). The proposed acylation proceeds through the following sequential reactions: aerobic oxidation of alcohols to aldehydes, nucleophilic addition of amides to the aldehydes to form hemiamidal intermediates, and aerobic oxidation of the hemiamidal intermediates to give the corresponding imides. This catalytic system utilizes O2 as the terminal oxidant and produces water as the sole by-product. An important point for realizing this efficient acylation system is the utilization of a TMEDA ligand, which, to the best of our knowledge, has not been employed in previously reported Cu/ligand/N-oxyl systems. Based on experimental evidence, we consider that plausible roles of TMEDA involve the promotion of both hemiamidal oxidation and regeneration of an active CuII-OH species from a CuI species. Here promotion of hemiamidal oxidation is particularly important. Employing the proposed system, various types of structurally diverse imides could be synthesized from various combinations of alcohols and amides, and gram-scale acylation was also successful. In addition, the proposed system was further applicable to the synthesis of α-ketocarbonyl compounds (i.e., α-ketoimides, α-ketoamides, and α-ketoesters) from 1,2-diols and nucleophiles (i.e., amides, amines, and alcohols).
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Affiliation(s)
- Kengo Kataoka
- Department of Applied Chemistry , School of Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan .
| | - Keiju Wachi
- Department of Applied Chemistry , School of Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan .
| | - Xiongjie Jin
- Department of Chemistry and Biotechnology , School of Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan .
| | - Kosuke Suzuki
- Department of Applied Chemistry , School of Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan .
| | - Yusuke Sasano
- Department of Organic Chemistry , Graduate School of Pharmaceutical Sciences , Tohoku University , 6-3 Aza-Aoba, Aramaki, Aoba-ku , Sendai 980-8578 , Japan
| | - Yoshiharu Iwabuchi
- Department of Organic Chemistry , Graduate School of Pharmaceutical Sciences , Tohoku University , 6-3 Aza-Aoba, Aramaki, Aoba-ku , Sendai 980-8578 , Japan
| | - Jun-Ya Hasegawa
- Institute for Catalysis , Hokkaido University , Kita 21 Nishi 10 , Kita-ku , Sapporo 001-0021 , Japan
| | - Noritaka Mizuno
- Department of Applied Chemistry , School of Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan .
| | - Kazuya Yamaguchi
- Department of Applied Chemistry , School of Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan .
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Busa AV, Lalancette R, Nordlander E, Onani M. New copper(II) salicylaldimine derivatives for mild oxidation of cyclohexane. J CHEM SCI 2018. [DOI: 10.1007/s12039-018-1455-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Dutta D, Phukan A, Dutta DK. Nanoporous montmorillonite clay stabilized copper nanoparticles: Efficient and reusable catalyst for oxidation of alcohols. MOLECULAR CATALYSIS 2018. [DOI: 10.1016/j.mcat.2017.12.032] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Riemer D, Mandaviya B, Schilling W, Götz AC, Kühl T, Finger M, Das S. CO2-Catalyzed Oxidation of Benzylic and Allylic Alcohols with DMSO. ACS Catal 2018. [DOI: 10.1021/acscatal.7b04390] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Daniel Riemer
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Bhavdip Mandaviya
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Waldemar Schilling
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Anne Charlotte Götz
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Torben Kühl
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Markus Finger
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Shoubhik Das
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
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Marais L, Burés J, Jordaan JHL, Mapolie S, Swarts AJ. A bis(pyridyl)-N-alkylamine/Cu(i) catalyst system for aerobic alcohol oxidation. Org Biomol Chem 2017; 15:6926-6933. [PMID: 28776055 DOI: 10.1039/c7ob01383c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein a bis(pyridyl)-N-alkylamine/CuI/TEMPO/NMI catalyst system is reported for aerobic oxidation of a variety of primary alcohols to the corresponding aldehydes using readily available reagents, at room temperature and ambient air as the oxidant. ESI-MS analysis of the reaction showed the formation of a [(L1)(NMI)CuII-OOH]+ species, which is a key intermediate in the alcohol oxidation reaction. Evaluation of the effect of reaction parameters on the initial rate of the reaction allowed us to obtain the optimum conditions for catalytic activity. The careful choice of reaction solvent allowed for the oxidation of 4-hydroxybenzyl alcohol, a substrate which proved problematic in previous studies. In the case of 2-pyridinemethanol as substrate, experimental evidence shows that catalytic activity is diminished due to competitive inhibition of the catalyst by the alcohol substrate.
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Affiliation(s)
- Lindie Marais
- Catalysis and Synthesis Research Group, Focus Area for Chemical Resource Beneficiation, North-West University, 11 Hoffman Street, Potchefstroom 2520, South Africa.
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Anchoring of Copper(II) Schiff Base Complex into Aminopropyl-Functionalised MCM-41: A Novel, Efficient and Reusable Catalyst for Selective Oxidation of Alcohols. J Inorg Organomet Polym Mater 2017. [DOI: 10.1007/s10904-017-0647-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Copper(II) complex of a Schiff base of dehydroacetic acid: Characterization and aerobic oxidation of benzyl alcohol. INORG CHEM COMMUN 2016. [DOI: 10.1016/j.inoche.2016.07.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Hussain MA, Joseph N, Kang O, Cho YH, Um BH, Kim JW. Supported Metal Nanoparticles: Their Catalytic Applications to Selective Alcohol Oxidation. APPLIED CHEMISTRY FOR ENGINEERING 2016. [DOI: 10.14478/ace.2016.1047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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You Q, Wang F, Wu C, Shi T, Min D, Chen H, Zhang W. Synthesis of 1,3,5-triazines via Cu(OAc)2-catalyzed aerobic oxidative coupling of alcohols and amidine hydrochlorides. Org Biomol Chem 2016; 13:6723-7. [PMID: 25991063 DOI: 10.1039/c5ob00724k] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Cu(OAc)2 was found to be an efficient catalyst for dehydrogenative synthesis of 1,3,5-triazine derivatives via oxidative coupling reaction of amidine hydrochlorides and alcohols in air. Both aromatic and aliphatic alcohols can be involved in the reaction and thirty-three products were obtained with good to excellent yields. Moreover, the use of a ligand, strong base and organic oxidant is unnecessary.
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Affiliation(s)
- Qing You
- Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, People's Republic of China.
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Safaei E, Hajikhanmirzaei L, Karimi B, Wojtczak A, Cotič P, Lee YI. TEMPO-mediated aerobic oxidation of alcohols using copper(II) complex of bis(phenol) di-amine ligand as biomimetic model for Galactose oxidase enzyme. Polyhedron 2016. [DOI: 10.1016/j.poly.2015.11.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Jain R, Gibson TJ, Mashuta MS, Buchanan RM, Grapperhaus CA. Copper catalysed aerobic oxidation of benzylic alcohols in an imidazole containing N4 ligand framework. Dalton Trans 2016; 45:18356-18364. [DOI: 10.1039/c6dt03395d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The catalytic aerobic oxidation of benzylic alcohols to corresponding aldehydes has been investigated employing a tetradentate copper(ii) complex that incorporates N-methyl imidazole (NMI) as an integral part of an N4-ligand framework.
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Affiliation(s)
- Rahul Jain
- Department of Chemistry
- University of Louisville
- Louisville
- USA
| | - Tony J. Gibson
- Department of Chemistry
- University of Louisville
- Louisville
- USA
| | - Mark S. Mashuta
- Department of Chemistry
- University of Louisville
- Louisville
- USA
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Bhat PB, Rajarao R, Sahajwalla V, Bhat BR. Immobilized magnetic nano catalyst for oxidation of alcohol. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.molcata.2015.08.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Zhang YC, Huang R, Lü FL, Cao XH, Zhao JQ. Aerobic oxidation of alcohols by copper(I)/benzoxazine ligand/TEMPO under mild and base-free conditions. RUSS J GEN CHEM+ 2015. [DOI: 10.1134/s1070363215080277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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27
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Sarma K, Devi N, Kalita M, Sarma B, Barman P. Nickel(II), copper(II), cobalt(II), and palladium(II) complexes with a Schiff base: crystal structure, DFT study and copper complex catalyzed aerobic oxidation of alcohol to aldehyde. J COORD CHEM 2015. [DOI: 10.1080/00958972.2015.1075241] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Kuladip Sarma
- Department of Chemistry, National Institute of Technology, Silchar, India
| | - Namita Devi
- Department of Chemistry, National Institute of Technology, Silchar, India
| | - Mukul Kalita
- Department of Chemistry, National Institute of Technology, Silchar, India
| | - Bipul Sarma
- Department of Chemical Sciences, Tezpur University, Tezpur, India
| | - Pranjit Barman
- Department of Chemistry, National Institute of Technology, Silchar, India
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28
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N-Heterocyclic carbene-catalyzed aerobic oxidation of aryl alkyl alcohols to carboxylic acids. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.03.072] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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29
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Baruah D, Saikia UP, Pahari P, Konwar D. Cu-nanoparticles on cellulose/H2O–CH3CN/microwave: a green system for the selective oxidation of alcohols to aldehydes. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2015.03.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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30
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Chen T, Cai C. Selective Oxidation of Benzyl Alcohols to Aldehydes with a Salophen Copper(II) Complex and tert-Butyl Hydroperoxide at Room Temperature. SYNTHETIC COMMUN 2015. [DOI: 10.1080/00397911.2015.1015034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Tingting Chen
- Chemical Engineering College, Nanjing University of Science and Technology, Nanjing, China
| | - Chun Cai
- Chemical Engineering College, Nanjing University of Science and Technology, Nanjing, China
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31
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Kang YW, Cho YJ, Ko KY, Jang HY. Copper-catalyzed carbon–carbon bond cleavage of primary propargyl alcohols: β-carbon elimination of hemiaminal intermediates. Catal Sci Technol 2015. [DOI: 10.1039/c5cy00783f] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The copper-catalyzed β-carbon elimination of primary propargyl alcohols via hemiaminals is studied under aerobic oxidation conditions.
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Affiliation(s)
- Ye-Won Kang
- Department of Energy Systems Research
- Ajou University
- Suwon 443-749
- Korea
| | - Yu Jin Cho
- Department of Energy Systems Research
- Ajou University
- Suwon 443-749
- Korea
| | - Kwang-Youn Ko
- Department of Chemistry
- Ajou University
- Suwon 443-749
- Korea
| | - Hye-Young Jang
- Department of Energy Systems Research
- Ajou University
- Suwon 443-749
- Korea
- Korea Carbon Capture & Seqeustration R&D Center
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32
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33
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Das OINDRILA, Paine TAPANKANTI. Copper Catalysts for Aerobic Oxidation of Alcohols. TRANSITION METAL CATALYSIS IN AEROBIC ALCOHOL OXIDATION 2014. [DOI: 10.1039/9781782621652-00040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Inspired by reactions catalyzed by galactose oxidase, a copper-containing enzyme, extensive studies were carried out on copper-based catalysts for alcohol oxidation using O2 as the terminal oxidant. Significant advances have been made towards the development of homogeneous and heterogeneous copper catalysts. These advances over the past decades are reviewed.
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Affiliation(s)
- OINDRILA Das
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science 2A&2B Raja S. C. Mullick Road, Jadavpur Kolkata 700032 India
| | - TAPAN KANTI Paine
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science 2A&2B Raja S. C. Mullick Road, Jadavpur Kolkata 700032 India
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34
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Yu J, Luan Y, Qi Y, Hou J, Dong W, Yang M, Wang G. Hierarchical PS/PANI nanostructure supported Cu(ii) complexes: facile synthesis and study of catalytic applications in aerobic oxidation. RSC Adv 2014. [DOI: 10.1039/c4ra06944g] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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35
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Kang YW, Choi YJ, Jang HY. Copper-Catalyzed TEMPO Addition to Propargyl Alcohols for the Synthesis of Vinylic Alkoxyamines. Org Lett 2014; 16:4842-5. [DOI: 10.1021/ol502341f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Ye-Won Kang
- Department
of Energy Systems Research, Ajou University, Suwon 443-749, Korea
| | - Yoon-Jeong Choi
- Department
of Energy Systems Research, Ajou University, Suwon 443-749, Korea
| | - Hye-Young Jang
- Department
of Energy Systems Research, Ajou University, Suwon 443-749, Korea
- Korea Carbon Capture & Sequestration R&D Center, Deajeon 305-343, Korea
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36
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An efficient and reusable vanadium based catalytic system for room temperature oxidation of alcohols to aldehydes and ketones. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.07.047] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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37
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Ryland BL, Stahl SS. Practical aerobic oxidations of alcohols and amines with homogeneous copper/TEMPO and related catalyst systems. Angew Chem Int Ed Engl 2014; 53:8824-38. [PMID: 25044821 PMCID: PMC4165639 DOI: 10.1002/anie.201403110] [Citation(s) in RCA: 397] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Indexed: 12/25/2022]
Abstract
Oxidations of alcohols and amines are common reactions in the synthesis of organic molecules in the laboratory and industry. Aerobic oxidation methods have long been sought for these transformations, but few practical methods exist that offer advantages over traditional oxidation methods. Recently developed homogeneous Cu/TEMPO (TEMPO = 2,2,6,6-tetramethylpiperidinyl-N-oxyl) and related catalyst systems appear to fill this void. The reactions exhibit high levels of chemoselectivity and broad functional-group tolerance, and they often operate efficiently at room temperature with ambient air as the oxidant. These advances, together with their historical context and recent applications, are highlighted in this Minireview.
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Affiliation(s)
- Bradford L. Ryland
- Department of Chemistry, University of Wisconsin- Madison 1101 University Avenue, Madison, Wisconsin 53706 (USA)
| | - Shannon S. Stahl
- Department of Chemistry, University of Wisconsin- Madison 1101 University Avenue, Madison, Wisconsin 53706 (USA)
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38
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Ryland BL, Stahl SS. Praktische aerobe Oxidationen von Alkoholen und Aminen mit dem homogenen Kupfer/TEMPO- und verwandten Katalysatorsystemen. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201403110] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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39
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Dewan A. A Highly Efficient and Inexpensive Palladium-Salen Complex for Room Temperature Suzuki-Miyaura Reaction. B KOREAN CHEM SOC 2014. [DOI: 10.5012/bkcs.2014.35.6.1855] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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40
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Borthakur R, Asthana M, Saha M, Kumar A, Pal AK. An efficient oxidation of alcohols using a new trinuclear copper complex as a reusable catalyst under solvent free conditions. RSC Adv 2014. [DOI: 10.1039/c4ra01275e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A new copper complex has shown efficacy as a catalyst for the selective oxidation of different alcohols using H2O2 as an oxidant under solvent free conditions.
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Affiliation(s)
- Rosmita Borthakur
- Department of Chemistry
- Centre for Advanced Studies in Chemistry
- North-Eastern Hill University
- Shillong-793022, India
| | - Mrityunjaya Asthana
- Department of Chemistry
- Centre of Advanced Study
- Banaras Hindu University
- Varanasi-221005, India
| | - Mithu Saha
- Department of Chemistry
- Centre for Advanced Studies in Chemistry
- North-Eastern Hill University
- Shillong-793022, India
| | - Arvind Kumar
- Department of Chemistry
- Faculty of Science and Agriculture
- The University of West-Indies
- St Augustine, West-Indies
| | - Amarta Kumar Pal
- Department of Chemistry
- Centre for Advanced Studies in Chemistry
- North-Eastern Hill University
- Shillong-793022, India
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41
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Highly efficient and selective aerobic oxidation of alcohols in aqueous media by TEMPO-containing catalytic systems. CATAL COMMUN 2014. [DOI: 10.1016/j.catcom.2013.09.022] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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42
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Ho XH, Jung WJ, Shyam PK, Jang HY. Copper–dienamine catalysis: γ-oxyamination of α,β-unsaturated aldehydes. Catal Sci Technol 2014. [DOI: 10.1039/c4cy00271g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A multicatalytic system composed of copper complexes and sec-amine compounds is proposed for γ-oxyamination of α,β-unsaturated aldehydes.
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Affiliation(s)
- Xuan-Huong Ho
- Division of Energy Systems Research
- Ajou University
- Suwon 443-749, Korea
| | - Won-Ji Jung
- Division of Energy Systems Research
- Ajou University
- Suwon 443-749, Korea
| | - Pranab K. Shyam
- Division of Energy Systems Research
- Ajou University
- Suwon 443-749, Korea
| | - Hye-Young Jang
- Division of Energy Systems Research
- Ajou University
- Suwon 443-749, Korea
- Korea Carbon Capture & Sequestration R&D Center
- Deajeon 305-343, Korea
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43
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Aerobic oxidation of p-cresols to 4-hydroxy benzaldehydes catalyzed by cobaltous chloride/NHPI/salen-Cu(II) catalytic system. RESEARCH ON CHEMICAL INTERMEDIATES 2013. [DOI: 10.1007/s11164-013-1494-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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44
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Allen SE, Walvoord RR, Padilla-Salinas R, Kozlowski MC. Aerobic copper-catalyzed organic reactions. Chem Rev 2013; 113:6234-458. [PMID: 23786461 PMCID: PMC3818381 DOI: 10.1021/cr300527g] [Citation(s) in RCA: 1240] [Impact Index Per Article: 112.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Scott E. Allen
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Ryan R. Walvoord
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Rosaura Padilla-Salinas
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Marisa C. Kozlowski
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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45
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Lomont JP, Nguyen SC, Harris CB. Reactivity of TEMPO toward 16- and 17-electron organometallic reaction intermediates: a time-resolved IR study. J Am Chem Soc 2013; 135:11266-73. [PMID: 23819559 DOI: 10.1021/ja404476m] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The (2,2,6,6-tetramethylpiperidin-1-yl)oxyl radical (TEMPO) has been employed for an extensive range of chemical applications, ranging from organometallic catalysis to serving as a structural probe in biological systems. As a ligand in an organometallic complex, TEMPO can exhibit several distinct coordination modes. Here we use ultrafast time-resolved infrared spectroscopy to study the reactivity of TEMPO toward coordinatively unsaturated 16- and 17-electron organometallic reaction intermediates. TEMPO coordinates to the metal centers of the 16-electron species CpCo(CO) and Fe(CO)4, and to the 17-electron species CpFe(CO)2 and Mn(CO)5, via an associative mechanism with concomitant oxidation of the metal center. In these adducts, TEMPO thus behaves as an anionic ligand, characterized by a pyramidal geometry about the nitrogen center. Density functional theory calculations are used to facilitate interpretation of the spectra and to further explore the structures of the TEMPO adducts. To our knowledge, this study represents the first direct characterization of the mechanism of the reaction of TEMPO with coordinatively unsaturated organometallic complexes, providing valuable insight into its reactions with commonly encountered reaction intermediates. The similar reactivity of TEMPO toward each of the species studied suggests that these results can be considered representative of TEMPO's reactivity toward all low-valent transition metal complexes.
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Affiliation(s)
- Justin P Lomont
- Department of Chemistry, University of California, Berkeley, Berkeley 94720, California, USA
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46
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Kim JH, Park EJ, Lee HJ, Ho XH, Yoon HS, Kim P, Yun H, Jang HY. Tandem Iminium/Copper Catalysis: Highly Enantioselective Synthesis of α,β-Disubstituted Aldehydes. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300333] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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47
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Soroceanu A, Cazacu M, Shova S, Turta C, Kožíšek J, Gall M, Breza M, Rapta P, Mac Leod TCO, Pombeiro AJL, Telser J, Dobrov AA, Arion VB. Copper(II) Complexes with Schiff Bases Containing a Disiloxane Unit: Synthesis, Structure, Bonding Features and Catalytic Activity for Aerobic Oxidation of Benzyl Alcohol. Eur J Inorg Chem 2013. [DOI: 10.1002/ejic.201201080] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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48
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Hoover JM, Ryland BL, Stahl SS. Mechanism of copper(I)/TEMPO-catalyzed aerobic alcohol oxidation. J Am Chem Soc 2013; 135:2357-67. [PMID: 23317450 DOI: 10.1021/ja3117203] [Citation(s) in RCA: 390] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Homogeneous Cu/TEMPO catalyst systems (TEMPO = 2,2,6,6-tetramethylpiperidine-N-oxyl) have emerged as some of the most versatile and practical catalysts for aerobic alcohol oxidation. Recently, we disclosed a (bpy)Cu(I)/TEMPO/NMI catalyst system (NMI = N-methylimidazole) that exhibits fast rates and high selectivities, even with unactivated aliphatic alcohols. Here, we present a mechanistic investigation of this catalyst system, in which we compare the reactivity of benzylic and aliphatic alcohols. This work includes analysis of catalytic rates by gas-uptake and in situ IR kinetic methods and characterization of the catalyst speciation during the reaction by EPR and UV-visible spectroscopic methods. The data support a two-stage catalytic mechanism consisting of (1) "catalyst oxidation" in which Cu(I) and TEMPO-H are oxidized by O(2) via a binuclear Cu(2)O(2) intermediate and (2) "substrate oxidation" mediated by Cu(II) and the nitroxyl radical of TEMPO via a Cu(II)-alkoxide intermediate. Catalytic rate laws, kinetic isotope effects, and spectroscopic data show that reactions of benzylic and aliphatic alcohols have different turnover-limiting steps. Catalyst oxidation by O(2) is turnover limiting with benzylic alcohols, while numerous steps contribute to the turnover rate in the oxidation of aliphatic alcohols.
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Affiliation(s)
- Jessica M Hoover
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
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49
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Synthesis of Heterogeneous Copper Catalyst Based on Amino-Functionalized Triazine Rings Supported by Silica-Gel for Oxidation of Alcohols. J CHEM-NY 2013. [DOI: 10.1155/2013/749723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Amino-functionalized triazine supported on silica-gel was prepared. This new triazine derivate was applied as a coordinating agent for copper (II) and was characterized by different methods. The copper (II) content of the material was determined by atomic absorption. This novel transition metal supported on heterogeneous surface was used as an effective catalyst for oxidation of benzylic alcohols in the presence of H2O2. This catalyst can be reused without any significant loss of activity.
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50
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Zhang G, Han X, Luan Y, Wang Y, Wen X, Xu L, Ding C, Gao J. Copper-catalyzed aerobic alcohol oxidation under air in neat water by using a water-soluble ligand. RSC Adv 2013. [DOI: 10.1039/c3ra43366h] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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