1
|
Sutradhar S, Rahaman R, Bhattacharya S, Paul S, Paine TK. Oxygenolytic cleavage of 1,2-diols with dioxygen by a mononuclear nonheme iron complex: Mimicking the reaction of myo-inositol oxygenase. J Inorg Biochem 2024; 257:112611. [PMID: 38788359 DOI: 10.1016/j.jinorgbio.2024.112611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 05/08/2024] [Accepted: 05/09/2024] [Indexed: 05/26/2024]
Abstract
A mononuclear iron(II) complex, [(TpPh2)FeII(OTf)(CH3CN)] (1) (TpPh2 = hydrotris(3,5-diphenylpyrazol-1-yl)borate, OTf = triflate) has been isolated and its efficiency toward the aliphatic CC bond cleavage reaction of 1,2-diols with dioxygen has been investigated. Separate reactions between 1 and different 1,2-diolates form the corresponding iron(II)-diolate complexes in solution. While the iron(II) complex of the tetradentate TPA (tris(2-pyridylmethyl)amine) ligand is not efficient in affecting the CC cleavage of 1,2-diol with dioxygen, complex 1 displays catalytic activity to afford carboxylic acid and aldehyde. Isotope labeling studies with 18O2 reveal that one oxygen atom from dioxygen is incorporated into the carboxylic acid product. The oxygenative CC cleavage reactions occur on the 1,2-diols containing at least one α-H atom. The kinetic isotope effect value of 5.7 supports the abstraction of an α-H by an iron(III)-superoxo species to propagate the CC cleavage reactions. The oxidative cleavage of 1,2-diolates by the iron(II) complex mimics the reaction catalyzed by the nonheme diiron enzyme, myo-inositol oxygenase.
Collapse
Affiliation(s)
- Subhankar Sutradhar
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A&2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Rubina Rahaman
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A&2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India; Department of Chemistry, Krishnagar Government College, Krishnagar, West Bengal 741101, India
| | - Shrabanti Bhattacharya
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A&2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Satadal Paul
- Department of Chemistry, Bangabasi Morning College, 19 Rajkumar Chakraborty Sarani, Kolkata 700009, India
| | - Tapan Kanti Paine
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A&2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India.
| |
Collapse
|
2
|
Radical generation and fate control for photocatalytic biomass conversion. Nat Rev Chem 2022; 6:197-214. [PMID: 37117437 DOI: 10.1038/s41570-022-00359-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2022] [Indexed: 12/30/2022]
Abstract
Photocatalysis is an emerging approach for sustainable chemical production from renewable biomass under mild conditions. Active radicals are always generated as key intermediates, in which their high reactivity renders them versatile for various upgrading processes. However, controlling their reaction is a challenge, especially in highly functionalized biomass frameworks. In this Review, we summarize recent advanced photocatalytic systems for selective biomass valorization, with an emphasis on their distinct radical-mediated reaction patterns. The strategies for generating a specific radical intermediate and controlling its subsequent conversion towards desired chemicals are also highlighted, aiming to provide guidance for future studies. We believe that taking full advantage of the unique reactivity of radical intermediates would provide great opportunities to develop more efficient photocatalytic systems for biomass valorization.
Collapse
|
3
|
Lim SH, Jang H, Kim MJ, Wee KR, Lim DH, Kim YI, Cho DW. Visible-Light-Induced Selective C–C Bond Cleavage Reactions of Dimeric β-O-4 and β-1 Lignin Model Substrates Utilizing Amine-Functionalized Fullerene. J Org Chem 2022; 87:2289-2300. [DOI: 10.1021/acs.joc.1c01991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Suk Hyun Lim
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea
| | - Hannara Jang
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea
| | - Min-Ji Kim
- Department of Chemistry and Institute of Natural Science, Daegu University, Gyeongsan 38453, Republic of Korea
| | - Kyung-Ryang Wee
- Department of Chemistry and Institute of Natural Science, Daegu University, Gyeongsan 38453, Republic of Korea
| | - Dong Hyun Lim
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea
| | - Young-Il Kim
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea
| | - Dae Won Cho
- Department of Chemistry, Yeungnam University, Gyeongsan, Gyeongbuk 38541, Korea
| |
Collapse
|
4
|
Lahive CW, Kamer PCJ, Lancefield CS, Deuss PJ. An Introduction to Model Compounds of Lignin Linking Motifs; Synthesis and Selection Considerations for Reactivity Studies. CHEMSUSCHEM 2020; 13:4238-4265. [PMID: 32510817 PMCID: PMC7540175 DOI: 10.1002/cssc.202000989] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Indexed: 05/31/2023]
Abstract
The development of fundamentally new valorization strategies for lignin plays a vital role in unlocking the true potential of lignocellulosic biomass as sustainable and economically compatible renewable carbon feedstock. In particular, new catalytic modification and depolymerization strategies are required. Progress in this field, past and future, relies for a large part on the application of synthetic model compounds that reduce the complexity of working with the lignin biopolymer. This aids the development of catalytic methodologies and in-depth mechanistic studies and guides structural characterization studies in the lignin field. However, due to the volume of literature and the piecemeal publication of methodology, the choice of suitable lignin model compounds is far from straight forward, especially for those outside the field and lacking a background in organic synthesis. For example, in catalytic depolymerization studies, a balance between synthetic effort and fidelity compared to the actual lignin of interest needs to be found. In this Review, we provide a broad overview of the model compounds available to study the chemistry of the main native linking motifs typically found in lignins from woody biomass, the synthetic routes and effort required to access them, and discuss to what extent these represent actual lignin structures. This overview can aid researchers in their selection of the most suitable lignin model systems for the development of emerging lignin modification and depolymerization technologies, maximizing their chances of successfully developing novel lignin valorization strategies.
Collapse
Affiliation(s)
- Ciaran W. Lahive
- Department of Chemical Engineering (ENTEG)University of GroningenNijenborgh 49747 AGGroningenNetherlands
- School of Chemistry and Biomedical Science Research ComplexUniversity of St. Andrews and EaStCHEMNorth HaughSt. AndrewsFifeKY16 9STUnited Kingdom
| | - Paul C. J. Kamer
- School of Chemistry and Biomedical Science Research ComplexUniversity of St. Andrews and EaStCHEMNorth HaughSt. AndrewsFifeKY16 9STUnited Kingdom
- Leibniz-Institut für Katalyse e.V.Albert-Einstein-Straße 29a18059RostockGermany
| | - Christopher S. Lancefield
- School of Chemistry and Biomedical Science Research ComplexUniversity of St. Andrews and EaStCHEMNorth HaughSt. AndrewsFifeKY16 9STUnited Kingdom
| | - Peter J. Deuss
- Department of Chemical Engineering (ENTEG)University of GroningenNijenborgh 49747 AGGroningenNetherlands
| |
Collapse
|
5
|
Wu X, Luo N, Xie S, Zhang H, Zhang Q, Wang F, Wang Y. Photocatalytic transformations of lignocellulosic biomass into chemicals. Chem Soc Rev 2020; 49:6198-6223. [DOI: 10.1039/d0cs00314j] [Citation(s) in RCA: 175] [Impact Index Per Article: 43.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
This review highlights recent advances in photocatalytic transformations of lignocellulosic biomass (polysaccharides and lignin) into chemicals (in particular organic oxygenates).
Collapse
Affiliation(s)
- Xuejiao Wu
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials
- National Engineering Laboratory for Green Chemical Productions of Alcohols
- Ethers and Esters
- College of Chemistry and Chemical Engineering
| | - Nengchao Luo
- State Key Laboratory of Catalysis
- Dalian National Laboratory for Clean Energy
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
- Dalian 116023
| | - Shunji Xie
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials
- National Engineering Laboratory for Green Chemical Productions of Alcohols
- Ethers and Esters
- College of Chemistry and Chemical Engineering
| | - Haikun Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials
- National Engineering Laboratory for Green Chemical Productions of Alcohols
- Ethers and Esters
- College of Chemistry and Chemical Engineering
| | - Qinghong Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials
- National Engineering Laboratory for Green Chemical Productions of Alcohols
- Ethers and Esters
- College of Chemistry and Chemical Engineering
| | - Feng Wang
- State Key Laboratory of Catalysis
- Dalian National Laboratory for Clean Energy
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
- Dalian 116023
| | - Ye Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces
- Collaborative Innovation Center of Chemistry for Energy Materials
- National Engineering Laboratory for Green Chemical Productions of Alcohols
- Ethers and Esters
- College of Chemistry and Chemical Engineering
| |
Collapse
|
6
|
Nguyen ST, Murray PRD, Knowles RR. Light-Driven Depolymerization of Native Lignin Enabled by Proton-Coupled Electron Transfer. ACS Catal 2019. [DOI: 10.1021/acscatal.9b04813] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Suong T. Nguyen
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Philip R. D. Murray
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Robert R. Knowles
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| |
Collapse
|
7
|
Liu H, Li H, Luo N, Wang F. Visible-Light-Induced Oxidative Lignin C–C Bond Cleavage to Aldehydes Using Vanadium Catalysts. ACS Catal 2019. [DOI: 10.1021/acscatal.9b03768] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Huifang Liu
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China
| | - Hongji Li
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Nengchao Luo
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Feng Wang
- State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China
| |
Collapse
|
8
|
Zhao X, Yang Y, Zhu R, Liu C, Zhang D. Mechanistic picture of the redox-neutral C C bond cleavage in 1,3-dilignol lignin model compound catalyzed by [Ru(Cl)(H)(PPh3)3]/triphos. MOLECULAR CATALYSIS 2019. [DOI: 10.1016/j.mcat.2019.04.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
9
|
Schwarz J, König B. Visible-light mediated C-C bond cleavage of 1,2-diols to carbonyls by cerium-photocatalysis. Chem Commun (Camb) 2019; 55:486-488. [PMID: 30548043 DOI: 10.1039/c8cc09208g] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We describe a photocatalytic method for the cleavage of vicinal diols to aldehydes and ketones. The reaction is catalyzed by blue light and a cerium-catalyst and the scope includes aryl as well as alkyl substituted diols. The simple protocol which works under air and at room temperature enables the valorization of abundant diols.
Collapse
Affiliation(s)
- Johanna Schwarz
- Institute of Organic Chemistry, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
| | | |
Collapse
|
10
|
Sivaguru P, Wang Z, Zanoni G, Bi X. Cleavage of carbon–carbon bonds by radical reactions. Chem Soc Rev 2019; 48:2615-2656. [DOI: 10.1039/c8cs00386f] [Citation(s) in RCA: 165] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This review provides insights into the in situ generated radicals triggered carbon–carbon bond cleavage reactions.
Collapse
Affiliation(s)
- Paramasivam Sivaguru
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis
- Northeast Normal University
- Changchun 130024
- China
| | - Zikun Wang
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis
- Northeast Normal University
- Changchun 130024
- China
| | | | - Xihe Bi
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis
- Northeast Normal University
- Changchun 130024
- China
| |
Collapse
|
11
|
Zhou W, Nakahashi J, Miura T, Murakami M. Light/Copper Relay for Aerobic Fragmentation of Lignin Model Compounds. ASIAN J ORG CHEM 2018. [DOI: 10.1002/ajoc.201800520] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Wang Zhou
- Department of Synthetic Chemistry and Biological Chemistry Kyoto University, Katsura Kyoto 615-8510 Japan
| | - Junki Nakahashi
- Department of Synthetic Chemistry and Biological Chemistry Kyoto University, Katsura Kyoto 615-8510 Japan
| | - Tomoya Miura
- Department of Synthetic Chemistry and Biological Chemistry Kyoto University, Katsura Kyoto 615-8510 Japan
| | - Masahiro Murakami
- Department of Synthetic Chemistry and Biological Chemistry Kyoto University, Katsura Kyoto 615-8510 Japan
| |
Collapse
|
12
|
Review on Catalytic Cleavage of C–C Inter-unit Linkages in Lignin Model Compounds: Towards Lignin Depolymerisation. Top Catal 2018. [DOI: 10.1007/s11244-018-0909-2] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
13
|
Affiliation(s)
- Norbert Hoffmann
- CNRS Université de Reims Champagne-Ardenne; ICMR; Université de Reims Champagne-Ardenne; B.P. 1039 51687 Reims France
| |
Collapse
|
14
|
Nguyen BH, Perkins RJ, Smith JA, Moeller KD. Solvolysis, Electrochemistry, and Development of Synthetic Building Blocks from Sawdust. J Org Chem 2015; 80:11953-62. [PMID: 26544912 DOI: 10.1021/acs.joc.5b01776] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Either aldehyde or cinnamyl ether products can be selectively extracted from raw sawdust by controlling the temperature and pressure of a solvolysis reaction. These materials have been used as platform chemicals for the synthesis of 15 different synthetic substrates. The conversion of the initial sawdust-derived materials into electron-rich aryl substrates often requires the use of oxidation and reduction chemistry, and the role electrochemistry can play as a sustainable method for these transformations has been defined.
Collapse
Affiliation(s)
- Bichlien H Nguyen
- Department of Chemistry, Washington University in St. Louis , St. Louis, Missouri 63130, United States
| | - Robert J Perkins
- Department of Chemistry, Washington University in St. Louis , St. Louis, Missouri 63130, United States
| | - Jake A Smith
- Department of Chemistry, Washington University in St. Louis , St. Louis, Missouri 63130, United States
| | - Kevin D Moeller
- Department of Chemistry, Washington University in St. Louis , St. Louis, Missouri 63130, United States
| |
Collapse
|
15
|
Li C, Zhao X, Wang A, Huber GW, Zhang T. Catalytic Transformation of Lignin for the Production of Chemicals and Fuels. Chem Rev 2015; 115:11559-624. [PMID: 26479313 DOI: 10.1021/acs.chemrev.5b00155] [Citation(s) in RCA: 1007] [Impact Index Per Article: 111.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Changzhi Li
- State Key Laborotary of Catalysis, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, China
| | - Xiaochen Zhao
- State Key Laborotary of Catalysis, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, China
| | - Aiqin Wang
- State Key Laborotary of Catalysis, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, China
| | - George W Huber
- State Key Laborotary of Catalysis, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, China.,Department of Chemical and Biological Engineering, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Tao Zhang
- State Key Laborotary of Catalysis, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, China
| |
Collapse
|
16
|
Lim SH, Lee WS, Kim YI, Sohn Y, Cho DW, Kim C, Kim E, Latham JA, Dunaway-Mariano D, Mariano PS. Photochemical and enzymatic SET promoted C–C bond cleavage reactions of lignin β-1 model compounds containing varying number of methoxy substituents on their arene rings. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.04.077] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
17
|
vom Stein T, den Hartog T, Buendia J, Stoychev S, Mottweiler J, Bolm C, Klankermayer J, Leitner W. Ruthenium-Catalyzed CC Bond Cleavage in Lignin Model Substrates. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201410620] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
18
|
vom Stein T, den Hartog T, Buendia J, Stoychev S, Mottweiler J, Bolm C, Klankermayer J, Leitner W. Ruthenium-catalyzed C-C bond cleavage in lignin model substrates. Angew Chem Int Ed Engl 2015; 54:5859-63. [PMID: 25809138 DOI: 10.1002/anie.201410620] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 02/25/2015] [Indexed: 11/08/2022]
Abstract
Ruthenium-triphos complexes exhibited unprecedented catalytic activity and selectivity in the redox-neutral C-C bond cleavage of the β-O-4 lignin linkage of 1,3-dilignol model compounds. A mechanistic pathway involving a dehydrogenation-initiated retro-aldol reaction for the C-C bond cleavage was proposed in line with experimental data and DFT calculations.
Collapse
Affiliation(s)
- Thorsten vom Stein
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany) www.itmc.rwth-aachen.de
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Effective C–O Bond Cleavage of Lignin β-O-4 Model Compounds: A New RuHCl(CO)(PPh3)3/KOH Catalytic System. Catal Letters 2014. [DOI: 10.1007/s10562-014-1264-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
20
|
Sedai B, Díaz-Urrutia C, Baker RT, Wu R, Silks LA“P, Hanson SK. Aerobic Oxidation of β-1 Lignin Model Compounds with Copper and Oxovanadium Catalysts. ACS Catal 2013. [DOI: 10.1021/cs400636k] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Baburam Sedai
- Department
of Chemistry and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, ON K1N 6N5 Canada
| | - Christian Díaz-Urrutia
- Department
of Chemistry and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, ON K1N 6N5 Canada
| | - R. Tom Baker
- Department
of Chemistry and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, ON K1N 6N5 Canada
| | | | | | | |
Collapse
|
21
|
Lim SH, Nahm K, Ra CS, Cho DW, Yoon UC, Latham JA, Dunaway-Mariano D, Mariano PS. Effects of alkoxy groups on arene rings of lignin β-O-4 model compounds on the efficiencies of single electron transfer-promoted photochemical and enzymatic C-C Bond Cleavage Reactions. J Org Chem 2013; 78:9431-43. [PMID: 23992466 DOI: 10.1021/jo401680z] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To gain information about how alkoxy substitution in arene rings of β-O-4 structural units within lignin governs the efficiencies/rates of radical cation C1-C2 bond cleavage reactions, single electron transfer (SET) photochemical and lignin peroxidase-catalyzed oxidation reactions of dimeric/tetrameric model compounds have been explored. The results show that the radical cations derived from less alkoxy-substituted dimeric β-O-4 models undergo more rapid C1-C2 bond cleavage than those of more alkoxy-substituted analogues. These findings gained support from the results of DFT calculations, which demonstrate that C1-C2 bond dissociation energies of β-O-4 radical cations decrease as the degree of alkoxy substitution decreases. In SET reactions of tetrameric compounds consisting of two β-O-4 units, containing different degrees of alkoxy substitution, regioselective radical cation C-C bond cleavage was observed to occur in one case at the C1-C2 bond in the less alkoxy-substituted β-O-4 moiety. However, regioselective C1-C2 cleavage in the more alkoxy-substituted β-O-4 moiety was observed in another case, suggesting that other factors might participate in controlling this process. These observations show that lignins containing greater proportions of less rather than more alkoxylated rings as part of β-O-4 units would be more efficiently cleaved by SET mechanisms.
Collapse
Affiliation(s)
- Suk Hyun Lim
- Department of Chemistry, Yeungnam University , Gyeongsan, Gyeongbuk 712-749, Korea
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Buendia J, Mottweiler J, Bolm C. Preparation of Diastereomerically Pure Dilignol Model Compounds. Chemistry 2011; 17:13877-82. [DOI: 10.1002/chem.201101579] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 08/31/2011] [Indexed: 11/06/2022]
|