1
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Iwasaki T, Nozaki K. Counterintuitive chemoselectivity in the reduction of carbonyl compounds. Nat Rev Chem 2024; 8:518-534. [PMID: 38831138 DOI: 10.1038/s41570-024-00608-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2024] [Indexed: 06/05/2024]
Abstract
The reactivity of carbonyl functional groups largely depends on the substituents on the carbon atom. Reversal of the commonly accepted order of reactivity of different carbonyl compounds requires novel synthetic approaches. Achieving selective reduction will enable the transformation of carbon resources such as plastic waste, carbon dioxide and biomass into valuable chemicals. In this Review, we explore the reduction of less reactive carbonyl groups in the presence of those typically considered more reactive. We discuss reductions, including the controlled reduction of ureas, amides and esters to aldehydes, as well as chemoselective reductions of carbonyl groups, including the reduction of ureas over carbamates, amides and esters; the reduction of amides over esters, ketones and aldehydes; and the reduction of ketones over aldehydes.
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Affiliation(s)
- Takanori Iwasaki
- Department of Chemistry and Biotechnology, The University of Tokyo, Tokyo, Japan.
| | - Kyoko Nozaki
- Department of Chemistry and Biotechnology, The University of Tokyo, Tokyo, Japan
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2
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O’Dea R, Nandi M, Kroll G, Arnold JR, Korley LTJ, Epps TH. Toward Circular Recycling of Polyurethanes: Depolymerization and Recovery of Isocyanates. JACS AU 2024; 4:1471-1479. [PMID: 38665666 PMCID: PMC11040557 DOI: 10.1021/jacsau.4c00013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 02/29/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024]
Abstract
We report a depolymerization strategy to nearly quantitatively regenerate isocyanates from thermoplastic and thermoset polyurethanes (PUs) and then resynthesize PUs using the recovered isocyanates. To date, chemical/advanced recycling of PUs has focused primarily on the recovery of polyols and diamines under comparatively harsh conditions (e.g., high pressure and temperature), and the recovery of isocyanates has been difficult. Our approach leverages an organoboron Lewis acid to depolymerize PUs directly to isocyanates under mild conditions (e.g., ∼80 °C in toluene) without the need for phosgene or other harsh reagents, and we show that both laboratory-synthesized and commercially sourced PUs can be depolymerized. Furthermore, we demonstrate the utility of the recovered isocyanate in the production of second-generation PUs with thermal properties and molecular weights similar to those of the virgin PUs. Overall, this route uniquely provides an opportunity for circularity in PU materials and can add significant value to end-of-life PU products.
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Affiliation(s)
- Robert
M. O’Dea
- Department
of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
- Center
for Plastics Innovation, University of Delaware, Newark, Delaware 19716, United States
| | - Mridula Nandi
- Department
of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Genevieve Kroll
- Department
of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Jackie R. Arnold
- Department
of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - LaShanda T. J. Korley
- Department
of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
- Center
for Plastics Innovation, University of Delaware, Newark, Delaware 19716, United States
- Department
of Materials Science and Engineering, University
of Delaware, Newark, Delaware 19716, United States
| | - Thomas H. Epps
- Department
of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
- Center
for Plastics Innovation, University of Delaware, Newark, Delaware 19716, United States
- Department
of Materials Science and Engineering, University
of Delaware, Newark, Delaware 19716, United States
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3
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Luk J, Oates CL, Fuentes Garcia JA, Clarke ML, Kumar A. Manganese-Catalyzed Hydrogenation of Amides and Polyurethanes: Is Catalyst Inhibition an Additional Barrier to the Efficient Hydrogenation of Amides and Their Derivatives? Organometallics 2024; 43:85-93. [PMID: 38274653 PMCID: PMC10806803 DOI: 10.1021/acs.organomet.3c00399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 01/27/2024]
Abstract
The hydrogenation of amides and other less electrophilic carbonyl derivatives with an N-C=O functionality requires significant improvements in scope and catalytic activity to be a genuinely useful reaction in industry. Here, we report the results of a study that examined whether such reactions are further disadvantaged by nitrogen-containing compounds such as aliphatic amines acting as inhibitors on the catalysts. In this case, an enantiomerically pure manganese catalyst previously established to be efficient in the hydrogenation of ketones, N-aryl-imines, and esters was used as a prototype of a manganese catalyst. This was accomplished by doping a model ester hydrogenation with various nitrogen-containing compounds and monitoring progress. Following from this, a protocol for the catalytic hydrogenation of amides and polyurethanes is described, including the catalytic hydrogenation of an axially chiral amide that resulted in low levels of kinetic resolution. The hypothesis of nitrogen-containing compounds acting as an inhibitor in the catalytic hydrogenation process has also been rationalized by using spectroscopy (high-pressure infrared (IR), nuclear magnetic resonance (NMR)) and mass spectrometry studies.
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Affiliation(s)
- James Luk
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K.
| | - Conor L. Oates
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K.
| | - José A. Fuentes Garcia
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K.
| | - Matthew L. Clarke
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K.
| | - Amit Kumar
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K.
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4
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Arifuzzaman M, Sumpter BG, Demchuk Z, Do C, Arnould MA, Rahman MA, Cao PF, Popovs I, Davis RJ, Dai S, Saito T. Selective deconstruction of mixed plastics by a tailored organocatalyst. MATERIALS HORIZONS 2023; 10:3360-3368. [PMID: 37482885 DOI: 10.1039/d3mh00801k] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
Plastic represents an essential material in our society; however, a major imbalance between their high production and end-of-life management is leading to unrecovered energy, economic hardship, and a high carbon footprint. The adoption of plastic recycling has been limited, mainly due to the difficulty of recycling mixed plastics. Here, we report a versatile organocatalyst for selective glycolysis of diverse consumer plastics and their mixed waste streams into valuable chemicals. The developed organocatalyst selectively deconstructs condensation polymers at a specific temperature, and additives or other polymers such as polyolefin or cellulose can be readily separated from the mixed plastics, providing a chemical recycling path for many existing mixed plastics today. The Life Cycle Assessment indicates that the production of various condensation polymers from the deconstructed monomers will result in a significant reduction in greenhouse gas emissions and energy input, opening a new paradigm of plastic circularity toward a net-zero carbon society.
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Affiliation(s)
- Md Arifuzzaman
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
| | - Bobby G Sumpter
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Zoriana Demchuk
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
| | - Changwoo Do
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Mark A Arnould
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Md Anisur Rahman
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
| | - Peng-Fei Cao
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
| | - Ilja Popovs
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
| | - Robert J Davis
- Department of Chemical Engineering, The University of Virginia, Charlottesville, VA 22904-4741, USA
| | - Sheng Dai
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
| | - Tomonori Saito
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
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5
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Livesay B, Schmidt JG, Williams RF, Billow BS, Tondreau AM. Reactivity of [(PNP)Mn(CO) 2] with Organophosphates. ACS ORGANIC & INORGANIC AU 2023; 3:199-208. [PMID: 37545657 PMCID: PMC10401673 DOI: 10.1021/acsorginorgau.3c00003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 04/20/2023] [Accepted: 04/24/2023] [Indexed: 08/08/2023]
Abstract
Organophosphorus nerve agents (OPAs) are a toxic class of synthetic compounds that cause adverse effects with many biological systems. Development of methods for environmental remediation and passivation has been ongoing for years. However, little progress has been made in therapeutic development for exposure victims. Given the postexposure behavior of OPA materials in enzymes such as acetylcholinesterase (AChE), development of electrophilic compounds as therapeutics may be more beneficial than the currently employed nucleophilic countermeasures. In this report, we present our studies with an electrophilic, 16-electron manganese complex (iPrPNP)Mn(CO)2 (1) and the nucleophilic hydroxide derivative (iPrPNHP)Mn(CO)2(OH) (2). The reactivity of 1 with phosphorus acids and the reactivity of 2 with the P-F bond of diisopropylfluorophosphate (DIPF) were studied. The role of water in both nucleophilic and electrophilic reactivity was investigated with the use of 17O-labeled water. Promising results arising from reactions of both 1 and 2 with organophosphorus substrates are reported.
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6
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Iwasaki T, Tsuge K, Naito N, Nozaki K. Chemoselectivity change in catalytic hydrogenolysis enabling urea-reduction to formamide/amine over more reactive carbonyl compounds. Nat Commun 2023; 14:3279. [PMID: 37308470 DOI: 10.1038/s41467-023-38997-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 05/24/2023] [Indexed: 06/14/2023] Open
Abstract
The selective transformation of a less reactive carbonyl moiety in the presence of more reactive ones can realize straightforward and environmentally benign chemical processes. However, such a transformation is highly challenging because the reactivity of carbonyl compounds, one of the most important functionalities in organic chemistry, depends on the substituents on the carbon atom. Herein, we report an Ir catalyst for the selective hydrogenolysis of urea derivatives, which are the least reactive carbonyl compounds, affording formamides and amines. Although formamide, as well as ester, amide, and carbamate substituents, are considered to be more reactive than urea, the proposed Ir catalyst tolerated these carbonyl groups and reacted with urea in a highly chemoselective manner. The proposed chemo- and regioselective hydrogenolysis allows the development of a strategy for the chemical recycling of polyurea resins.
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Affiliation(s)
- Takanori Iwasaki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
| | - Kazuki Tsuge
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Naoki Naito
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Kyoko Nozaki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
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7
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Olazabal I, González A, Vallejos S, Rivilla I, Jehanno C, Sardon H. Upgrading Polyurethanes into Functional Ureas through the Asymmetric Chemical Deconstruction of Carbamates. ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2023; 11:332-342. [PMID: 36643003 PMCID: PMC9832924 DOI: 10.1021/acssuschemeng.2c05647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/11/2022] [Indexed: 06/17/2023]
Abstract
The importance of systematic and efficient recycling of all forms of plastic is no longer a matter for debate. Constituting the sixth most produced polymer family worldwide, polyurethanes, which are used in a broad variety of applications (buildings, electronics, adhesives, sealants, etc.), are particularly important to recycle. In this study, polyurethanes are selectively recycled to obtain high value-added molecules. It is demonstrated that depolymerization reactions performed with secondary amines selectively cleave the C-O bond of the urethane group, while primary amines unselectively break C-O and C-N bonds. The selective cleavage of C-O bonds, catalyzed by an acid:base mixture, led to the initial polyol and a functional diurea in several hours to a few minutes for both model polyurethanes and commercial polyurethane foams. Different secondary amines were employed as nucleophiles to synthesize a small library of diureas obtained in good to excellent yields. This study not only targets the recovery of the initial polyol but also aims to form new diureas which are useful building blocks for the polymerization of innovative materials.
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Affiliation(s)
- Ion Olazabal
- POLYMAT,
University of the Basque Country UPV/EHU, Joxe Mari Korta Center, Avda. Tolosa 72, 20018 Donostia-San Sebastian, Spain
| | - Alba González
- POLYMAT,
University of the Basque Country UPV/EHU, Joxe Mari Korta Center, Avda. Tolosa 72, 20018 Donostia-San Sebastian, Spain
| | - Saúl Vallejos
- Department
of Chemistry, Faculty of Science, University
of Burgos, Plaza Misael Bañuelos s/n, 09001 Burgos, Spain
- CQC-IMS,
Department of Chemistry, University of Coimbra, Rua Larga, 3004-535 Coimbra, Portugal
| | - Iván Rivilla
- Departamento
de Química Orgánica I, Centro de Innovación en
Química Avanzada (ORFEO−CINQA), Facultad de Química, Universidad del País Vasco/Euskal Herriko Unibertsitatea
(UPV/EHU) and Donostia International Physics Center (DIPC), P° Manuel Lardizabal 3, 20018 San Sebastián-Donostia, Spain
- Ikerbasque, Basque Fundation for Science, 48009 Bilbao, Spain
| | - Coralie Jehanno
- POLYMAT,
University of the Basque Country UPV/EHU, Joxe Mari Korta Center, Avda. Tolosa 72, 20018 Donostia-San Sebastian, Spain
- POLYKEY, Joxe Mari Korta
Center, Avda. Tolosa
72, 20018 Donostia-San
Sebastian, Spain
| | - Haritz Sardon
- POLYMAT,
University of the Basque Country UPV/EHU, Joxe Mari Korta Center, Avda. Tolosa 72, 20018 Donostia-San Sebastian, Spain
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8
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Rong H, Zhang Y, Ai X, Li W, Cao F, Li L. Theoretical Study on the Hydrogenolysis of Polyurethanes to Improve the Catalytic Activities. Inorg Chem 2022; 61:14662-14672. [PMID: 36062933 DOI: 10.1021/acs.inorgchem.2c02027] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The metal-catalyzed hydrogenolysis of polymers is important in waste recycling; however, it is limited by the harsh reaction conditions and the low activities of catalysts, especially for earth-abundant metal-based catalysts. Herein, we perform a comprehensive study on the hydrogenolysis of polyurethane model catalyzed by Fe-, Mn-, Ru-, and Ir-iPrMACHO pincer complexes and propose a cascade mechanism comprising two-level hydrogenolysis and the hydrogenation of formaldehyde. In addition, the substrates and ligands are modulated to improve the activities of chemical recycling to monomer. It is found that the pincer ligands could dissociate from the metal centers at high reaction temperatures and further result in the deactivation of catalysts. The rigid Fe and Mn catalysts with tetradentate cyclic ligands are designed following the guidance, and the computations suggest that those designed catalysts could have high stabilities and activities.
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Affiliation(s)
- Hongli Rong
- College of Pharmacy, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, Hebei University, Baoding 071002, Hebei, P. R. China
| | - Yahui Zhang
- College of Pharmacy, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, Hebei University, Baoding 071002, Hebei, P. R. China
| | - Xinliang Ai
- College of Pharmacy, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, Hebei University, Baoding 071002, Hebei, P. R. China
| | - Wan Li
- College of Pharmacy, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, Hebei University, Baoding 071002, Hebei, P. R. China
| | - Fei Cao
- College of Pharmacy, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, Hebei University, Baoding 071002, Hebei, P. R. China
| | - Longfei Li
- College of Pharmacy, Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, Hebei University, Baoding 071002, Hebei, P. R. China
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9
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Owen AE, Preiss A, McLuskie A, Gao C, Peters G, Bühl M, Kumar A. Manganese-Catalyzed Dehydrogenative Synthesis of Urea Derivatives and Polyureas. ACS Catal 2022. [DOI: 10.1021/acscatal.2c00850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Annika Preiss
- School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY169ST, U.K
| | - Angus McLuskie
- School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY169ST, U.K
| | - Chang Gao
- School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY169ST, U.K
| | - Gavin Peters
- School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY169ST, U.K
| | - Michael Bühl
- School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY169ST, U.K
| | - Amit Kumar
- School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY169ST, U.K
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10
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Das K, Waiba S, Jana A, Maji B. Manganese-catalyzed hydrogenation, dehydrogenation, and hydroelementation reactions. Chem Soc Rev 2022; 51:4386-4464. [PMID: 35583150 DOI: 10.1039/d2cs00093h] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The emerging field of organometallic catalysis has shifted towards research on Earth-abundant transition metals due to their ready availability, economic advantage, and novel properties. In this case, manganese, the third most abundant transition-metal in the Earth's crust, has emerged as one of the leading competitors. Accordingly, a large number of molecularly-defined Mn-complexes has been synthesized and employed for hydrogenation, dehydrogenation, and hydroelementation reactions. In this regard, catalyst design is based on three pillars, namely, metal-ligand bifunctionality, ligand hemilability, and redox activity. Indeed, the developed catalysts not only differ in the number of chelating atoms they possess but also their working principles, thereby leading to different turnover numbers for product molecules. Hence, the critical assessment of molecularly defined manganese catalysts in terms of chelating atoms, reaction conditions, mechanistic pathway, and product turnover number is significant. Herein, we analyze manganese complexes for their catalytic activity, versatility to allow multiple transformations and their routes to convert substrates to target molecules. This article will also be helpful to get significant insight into ligand design, thereby aiding catalysis design.
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Affiliation(s)
- Kuhali Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India.
| | - Satyadeep Waiba
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India.
| | - Akash Jana
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India.
| | - Biplab Maji
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246, India.
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11
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Gausas L, Donslund BS, Kristensen SK, Skrydstrup T. Evaluation of Manganese Catalysts for the Hydrogenative Deconstruction of Commercial and End-of-Life Polyurethane Samples. CHEMSUSCHEM 2022; 15:e202101705. [PMID: 34510781 DOI: 10.1002/cssc.202101705] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/08/2021] [Indexed: 06/13/2023]
Abstract
Polyurethane (PU) is a thermoset plastic that is found in everyday objects, such as mattresses and shoes, but also in more sophisticated materials, including windmills and airplanes, and as insulation materials in refrigerators and buildings. Because of extensive inter-cross linkages in PU, current recycling methods are somewhat lacking. In this work, the effective catalytic hydrogenation of PU materials is carried out by applying a catalyst based on the earth-abundant metal manganese, to give amine and polyol fractions, which represent the original monomeric composition. In particular, Mn-Ph MACHO is found to catalytically deconstruct flexible foam, molded foams, insulation, and end-of-life materials at 1 wt.% catalyst loading by applying a reaction temperature of 180 °C, 50 bar of H2 , and 0.9 wt.% of KOH in isopropyl alcohol. The protocol is showcased in the catalytic deconstruction of 2 g of mattress foam using only 0.13 wt.% catalyst, resulting in 90 % weight recovery and a turnover number of 905.
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Affiliation(s)
- Laurynas Gausas
- Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and, Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Bjarke S Donslund
- Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and, Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Steffan K Kristensen
- Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Troels Skrydstrup
- Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and, Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
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12
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Liu X, Zuo Y, Kallmeier F, Mejía E, Tin S, de Vries JG, Barath E. Hydrogenative Depolymerization of Silicon-modified Polyureas. Chem Commun (Camb) 2022; 58:5415-5418. [DOI: 10.1039/d2cc01063a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Silicon-modified polyureas were depolymerized by hydrogenation in the presence of Ru and Mn catalysts. Yields of up to 84% of the aliphatic diamine and 81% of silicon-containing diamine were achieved...
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