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A Green Approach for the Reduction of Representative Aryl Functional

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A Green Approach for the Reduction of Representative Aryl Functional A green approach for the reduction of representative aryl functional groups using palladium ecocatalysts Claude Grison, Pauline Adler, Pierre-Alexandre Deyris, Sebastien Diliberto, Clotilde Boulanger To cite this version: Claude Grison, Pauline Adler, Pierre-Alexandre Deyris, Sebastien Diliberto, Clotilde Boulanger. A green approach for the reduction of representative aryl functional groups using palladium eco- catalysts. Green chemistry letters and reviews, Taylor & Francis, 2021, 14 (2), pp.233-244. 10.1080/17518253.2021.1898682. hal-03184149 HAL Id: hal-03184149 https://hal.archives-ouvertes.fr/hal-03184149 Submitted on 29 Mar 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution| 4.0 International License Green Chemistry Letters and Reviews ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/tgcl20 A green approach for the reduction of representative aryl functional groups using palladium ecocatalysts Claude Grison, Pauline Adler, Pierre-Alexandre Deyris, Sebastien Diliberto & Clotilde Boulanger To cite this article: Claude Grison, Pauline Adler, Pierre-Alexandre Deyris, Sebastien Diliberto & Clotilde Boulanger (2021) A green approach for the reduction of representative aryl functional groups using palladium ecocatalysts, Green Chemistry Letters and Reviews, 14:2, 233-244, DOI: 10.1080/17518253.2021.1898682 To link to this article: https://doi.org/10.1080/17518253.2021.1898682 © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group Published online: 27 Mar 2021. Submit your article to this journal View related articles View Crossmark data Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=tgcl20 GREEN CHEMISTRY LETTERS AND REVIEWS 2021, VOL. 14, NO. 2, 233–244 https://doi.org/10.1080/17518253.2021.1898682 LETTER A green approach for the reduction of representative aryl functional groups using palladium ecocatalysts Claude Grison a, Pauline Adlera, Pierre-Alexandre Deyrisa, Sebastien Diliberto b and Clotilde Boulangerb aLaboratory of Bio-inspired Chemistry and Ecological Innovations UMR 5021 CNRS, University of Montpellier, Grabels, France; bInstitut Jean Lamour, UMR 7198, Centre National de la Recherche Scientifique, Université de Lorraine, Metz, France ABSTRACT ARTICLE HISTORY The reduction of functional groups has been thoroughly explored in organic synthesis. Received 26 November 2020 Nevertheless, most of the existing methodologies are based on conditions far from being Accepted 26 February 2021 environmentally friendly, which limits their usefulness. Here we report a green approach for the KEYWORDS reduction of representative aryl functional groups using Eco-Pd catalysts. The Eco-Pd catalysts fi Palladium; ecocatalyst; green were prepared from palladium enriched vegetal lters that biosorbed palladium from an reduction; microwave aquatic environment. The Eco-Pd catalysts were characterized by MP-AES XRPD and XPS, and activation; aryl halides; used in the reductions of aryl halides, aryl aldehydes and nitroarenes in green conditions. A aromatic aldehydes; mixture of glycerol and n-butanol was used, as the solvent system and as the reducing reagent, nitroarenes in the presence of non-hazardous inorganic bases and without any ligands. Although Eco-Pd catalysis within this solvent system was homogeneous, we were able to recover and reuse the ecocatalyst to efficiently catalyze new reduction reactions. 1. Introduction regulated by REACH (2). Moreover the metal hydrides and sources of hydride equivalents are used in stoichio- The reduction of functional groups is a ubiquitous trans- metric conditions and cannot be recycled, thus lead to formation in organic synthesis. A great variety of redu- higher E-factors (3). Reductions by dissolved metals cing systems has been described. The choice of a and related methods raise similar issues. reducing agent depends on the desired chemo-, regio- Another system involves the use of dihydrogen in and stereoselectivity. Many systems have been investi- hydrogenation or hydrogenolysis reactions. Various cat- gated to find the required reactivity. One of the most alysts (Ni, Fe, Pd, Pt, Ru, Rh, Os, Ir) are employed in micro used systems of reducing agents is based on the and macro scale under heterogeneous or homogeneous addition or substitution of a nucleophile hydride ion or conditions. Several factors such as the catalyst, the a radical. The reducing reagent can derive from alkali, support, the solvent, the temperature and the pressure alkaline earth or other metal hydrides (silicon, tin, tran- of dihydrogen affect the efficiency of the reduction. sition metals) or Lewis acids such as alanes or boranes. For example, it is well known that catalytic hydrogen- However, metal hydrides require aprotic and anhydrous ation is very sensitive to steric hindrance and can solvents, which can be hazardous, as THF, Et2O, Me2SO, require high temperature and pressure. These con- DMF, HMPA, PhCH3 (1). Most common alanes and alumi- ditions constitute an industrial risk. The price of PGMs nohydrides are inflammable, boranes, borohydrides and (platinum group metals) recently reached high records tin hydrides generate problematic wastes, which are due to their geo-economic context. The phenomenon CONTACT Claude Grison [email protected] Laboratory of Bio-inspired Chemistry and Ecological Innovations UMR 5021 CNRS, University of Montpellier, Cap Delta, 1682 Rue de la Valsière 34790, Grabels, France © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 234 P. ADLER ET AL. was reinforced by an increasing demand on world automatic background correction mode available in markets for PGMs such as Pd. the software was used. An Agilent SPS3 autosampler For the aforementioned reasons, the chemical industry was used throughout the study. is facing the imperative need to innovate for the develop- X-ray diffraction (XRD) data measurements on the ment of available, eco-friendly, sustainable and recyclable samples dried at 110°C for 2 h were performed by reducing catalytic systems. In this context, we studied the using a BRUKER diffractometer (D8 advance, with a Cu synthetic potential of a green and versatile reducing tool, Kα radiation λ = 1.54086 Å) equipped with a Lynxeyes called Eco-Pd. Eco-Pd has been developed during pio- detector. neering works of our research group on the ecological The XPS analyzes are carried out with the ESCALAB recycling of palladium from specific plants. 250 device from Thermo Electron. The source of exci- While investigating the remarkable sorption mechan- tation is the monochromatic source, Al Kα line ism realized by aquatic plant roots, it appeared that this (1486.6 eV). The analyzed surface has a diameter of phenomenon was unexpectedly chemical and not phys- 500 µm. Photoelectron spectra are calibrated as iological due to the presence of carboxylate and phenolic binding energy relative to the energy of the C–C com- groups that can chelate metallic elements without active ponent of C1s carbon at 284.8 eV. The charge is compen- internalization process. Our group could thus develop sated by an electron beam (−2 eV). new vegetal filters using dead aquatic plant roots Gas chromatography analyzes were performed using instead of living plants. The biosorption of transition a Thermo Scientific Trace 1300 device equipped with an metals was studied using these vegetal filters and EI ionization source and an ISQ-QD detector. The reac- showed a high efficiency. Pd-rich biomasses were ther- tions were monitored by using para–cymene as internal mally and chemically treated for the preparation of Eco- standard and FID methods for the calibration. Pd catalysts (4–9). The use of Eco-Pd led to high yields 1H NMR and 13C NMR spectra were recorded on a in cross-coupling reactions such as Sonogashira coupling. Bruker 400 AVANCE fitted with a dual 1H/13C-gradient In this work, we have extended Eco-Pd catalytic activi- Z probe at 400 and 100 MHz respectively and using ties in representative reduction reactions: microwave solvent as internal standard (7.26 ppm for 1H and 13 assisted reduction of aryl-bromides, -iodides and -alde- 77.16 ppm for C for CDCl3). hydes, and thermal reduction of nitroarenes. Some reactions were carried out using a microwave- assisted digestion method (Multiwave-Go Anton Paar) with the following program: 20–120°C in 1 min and 2. Materials and methods then 1 min isothermal at 120°C followed with 120–150° C in 1 min and finally 10 (aryl iodides), 15 (aryl bromides), 2.1. Reagents and instruments or 15–30 (aldehydes) min isothermal at 150°C. All reagents and solvents used in this work were pur- chased from commercial sources. Analyzes by MP–AES: 2.2. Biomaterial collection and preparation for The samples were digested in 10 mL of reversed aqua biosorption regia (1:2 hydrochloric acid (37%): nitric acid (65%)) under a microwave-assisted digestion (Multiwave-Go Anton Paar) with the following program: 20–165°C in . Eichhornia crassipes were purchased from a special- 20 min and then 10 min isothermal at 165°C. Samples ized grower (Nymphea company, France). The plants were filtered and then diluted to 0.4 mg.L−1 in 1% were placed in an outdoor tank under greenhouse aqueous nitric acid. Mineral compositions were deter- filled with water to which guano was added as mined by using a microwave plasma-atomic emission fertilizer.
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