1
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Lee B, Phillips AD, Hanif M, Söhnel T, Hartinger CG. Triazolyl- vs Pyridyl-Functionalized N-Heterocyclic Carbene Complexes: Impact of the Pendant N-Donor Ligand on Intramolecular C-C Bond Formation. ACS ORGANIC & INORGANIC AU 2022; 2:511-524. [PMID: 36510612 PMCID: PMC9732886 DOI: 10.1021/acsorginorgau.2c00035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/29/2022] [Accepted: 08/29/2022] [Indexed: 12/16/2022]
Abstract
Organometallic Rh(Cp*) (Cp* = η5-pentamethylcyclopentadienyl) complexes with monodentate N-heterocyclic carbene (NHC) ligands bearing a pendant anthracenyl substituent have been shown to undergo intramolecular C-C coupling reactions. Herein, two bidentate NHC ligands substituted with pyridyl or triazolyl donor groups were prepared along with the corresponding MII/III (M = RuII, OsII, RhIII, IrIII) complexes. While the Rh(Cp*) complex featuring an NHC-triazole bidentate ligand underwent the equivalent reaction as the monodentate Rh(NHC) complex, i.e., it formed a polydentate ligand, the pyridyl-pendant derivative was unequivocally shown to be unreactive. This contrasting behavior was further investigated by density functional theory (DFT) calculations that highlighted significant differences between the two types of Rh(III) complexes with pendant pyridyl or triazolyl N-coordinating groups. Modeling of the reaction pathways suggests that the initial formation of a dicationic Rh(III) species is unfavorable and that the internal ligand transformation proceeds first by dissociation of the coordinated N atom of the pendant group from the Rh center. After the formation of a neutral η4-fulvene ligand via combined proton/single electron transfer, a cycloaddition occurs between the exo-ene bond of fulvene and the 9' and 10' positions on the pendant anthracenyl group. The resulting experimental UV-visible spectrum recorded in methanol of the polydentate triazolyl-based Rh species revealed the loss of the vibronic coupling typically associated with an anthracenyl functional group. Moreover, TD-DFT modeling indicates the presence of an equilibrium process whereby the N-coordination of the pendant triazolyl group to the RhIII center appears to be highly labile. Charge decomposition analysis (CDA) of the DFT-modeled species with the dissociated triazolyl group revealed a pseudo-η3-allylic interaction between the π-type MOs of the transformed anthracenyl group and the RhIII center; thus, the singly attached chelating ligand is classified as having rare nonadenticity.
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Affiliation(s)
- Betty
Y.T. Lee
- School
of Chemical Sciences, The University of
Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Andrew D. Phillips
- School
of Chemistry, University College Dublin, Belfield, Dublin 4 D04 V1W8, Ireland,
| | - Muhammad Hanif
- School
of Chemical Sciences, The University of
Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Tilo Söhnel
- School
of Chemical Sciences, The University of
Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Christian G. Hartinger
- School
of Chemical Sciences, The University of
Auckland, Private Bag 92019, Auckland 1142, New Zealand,
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2
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Nekrasov RI, Peganova TA, Fedyanin IV, Gutsul EI, Filippov OA, Belkova NV, Kalsin AM. Versatile Reactivity of Half-Sandwich Rhodium(III) Iminophosphonamide Complexes. Inorg Chem 2022; 61:16081-16092. [PMID: 36149890 DOI: 10.1021/acs.inorgchem.2c02478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Novel 18e̅ and 16e̅ pentamethylcyclopentadienyl rhodium(III) complexes [(η5-C5Me5)RhX(NPN)] (1a,b, X = Cl; 2a-c, X = PF6, BAr4F) with chelating zwitterionic iminophosphonamide (NPN) ligands (Ph2P(NR)(NR'); a, R = R' = p-Tol; b, R = p-Tol, R' = Me; c, R = R' = Me) were synthesized and characterized by single-crystal X-ray diffraction. In the 16e̅ complexes 2, the rhodium (Rh) atom is efficiently stabilized by π-donation of unshared N electrons, thus hampering coordination of the external ligands and rendering the 18e̅ complexes labile. Due to low coordination enthalpy, the cationic 18e̅ monocarbonyl and pyridine adducts 2a·L are stable only at low temperatures. At room temperature, 2·CO adducts readily give stable carbonyl-carbamoyl complexes [(η5-C5Me5)Rh(CO){(CO(NR')Ph2P(NR)}]+ (4) formed as a result of CO insertion into the Rh-N bond, thus showing high nucleophilicity of the N atoms in 18e̅ complexes. High basicity of the Na+NPN- precursors caused side deprotonation of the η5-C5Me5 ligand during the synthesis of 1 that yields unstable fulvene Rh(I) complexes [(η4-C5Me4CH2)Rh{Ph2P(NR)(NR')2}] (3a,b). Complex 3a undergoes a facile reaction with isoprene to yield an unusual [(η5:η1-C5Me4(CH2)C(Me)═CHCH2)Rh(NPN)] complex─the first example of intermolecular 1,4-metallacycloaddition of diene to the Rh-fulvene complex.
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Affiliation(s)
- Roman I Nekrasov
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilov Street, 119334 Moscow, Russian Federation
| | - Tat'yana A Peganova
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilov Street, 119334 Moscow, Russian Federation
| | - Ivan V Fedyanin
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilov Street, 119334 Moscow, Russian Federation
| | - Evgenii I Gutsul
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilov Street, 119334 Moscow, Russian Federation
| | - Oleg A Filippov
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilov Street, 119334 Moscow, Russian Federation
| | - Natalia V Belkova
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilov Street, 119334 Moscow, Russian Federation
| | - Alexander M Kalsin
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilov Street, 119334 Moscow, Russian Federation
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3
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Morgan P, Saunders GC, Macgregor SA, Marr AC, Licence P. Nucleophilic Fluorination Catalyzed by a Cyclometallated Rhodium Complex. Organometallics 2022; 41:883-891. [PMID: 35571260 PMCID: PMC9098193 DOI: 10.1021/acs.organomet.2c00052] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Indexed: 11/30/2022]
Abstract
Quantitative catalytic nucleophilic fluorination of a range of acyl chlorides to acyl fluorides was promoted by a cyclometallated rhodium complex [(η5,κ2C-C5Me4CH2C6F5CH2NC3H2NMe)- RhCl] (1). 1 can be prepared in high yields from commercially available starting materials using a one-pot method. The catalyst could be separated, regenerated, and reused. Rapid quantitative fluorination generated the fluoride analogue of the active pharmaceutical ingredient probenecid. Infrared in situ monitoring verified the clean conversion of the substrates to products. VTNA graphical kinetic analysis and DFT calculations lead to a postulated reaction mechanism involving a nucleophilic Rh-F bond.
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Affiliation(s)
- Patrick
J. Morgan
- GSK
Carbon Neutral Laboratory, School of Chemistry, University of Nottingham, Nottingham NG7 2TU, U.K.
| | | | - Stuart A. Macgregor
- School
of Engineering and Physical Sciences, Heriot-Watt
University, William H. Perkin Building, Edinburgh EH14 4AS, U.K.
| | - Andrew C. Marr
- School
of Chemistry and Chemical Engineering, Queen’s
University Belfast, David Keir Building, Belfast BT9 5AG, U.K.
| | - Peter Licence
- GSK
Carbon Neutral Laboratory, School of Chemistry, University of Nottingham, Nottingham NG7 2TU, U.K.
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4
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Evans KJ, Morton PA, Luz C, Miller C, Raine O, Lynam JM, Mansell SM. Rhodium Indenyl NHC and Fluorenyl-Tethered NHC Half-Sandwich Complexes: Synthesis, Structures and Applications in the Catalytic C-H Borylation of Arenes and Alkanes. Chemistry 2021; 27:17824-17833. [PMID: 34653269 PMCID: PMC9299238 DOI: 10.1002/chem.202102961] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Indexed: 01/11/2023]
Abstract
Indenyl (Ind) rhodium N-heterocyclic carbene (NHC) complexes [Rh(η5 -Ind)(NHC)(L)] were synthesised for 1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazol-2-ylidene (SIPr) with L=C2 H4 (1), CO (2 a) and cyclooctene (COE; 3), for 1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene (SIMes) with L=CO (2 b) and COE (4), and 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes) with L=CO (2 c) and COE (5). Reaction of SIPr with [Rh(Cp*)(C2 H4 )2 ] did not give the desired SIPr complex, thus demonstrating the "indenyl effect" in the synthesis of 1. Oxidative addition of HSi(OEt)3 to 3 proceeded under mild conditions to give the Rh silyl hydride complex [Rh(Ind){Si(OEt)3 }(H)(SIPr)] (6) with loss of COE. Tethered-fluorenyl NHC rhodium complexes [Rh{(η5 -C13 H8 )C2 H4 N(C)C2 Hx NR}(L)] (x=4, R=Dipp, L=C2 H4 : 11; L=COE: 12; L=CO: 13; R=Mes, L=COE: 14; L=CO: 15; x=2, R=Me, L=COE: 16; L=CO: 17) were synthesised in low yields (5-31 %) in comparison to good yields for the monodentate complexes (49-79 %). Compounds 3 and 1, which contain labile alkene ligands, were successful catalysts for the catalytic borylation of benzene with B2 pin2 (Bpin=pinacolboronate, 97 and 93 % PhBpin respectively with 5 mol % catalyst, 24 h, 80 °C), with SIPr giving a more active catalyst than SIMes or IMes. Fluorenyl-tethered NHC complexes were much less active as borylation catalysts, and the carbonyl complexes were inactive. The borylation of toluene, biphenyl, anisole and diphenyl ether proceeded to give meta substitutions as the major product, with smaller amounts of para substitution and almost no ortho product. The borylation of octane and decane with B2 pin2 at 120 and 140 °C, respectively, was monitored by 11 B NMR spectroscopy, which showed high conversions into octyl and decylBpin over 4-7 days, thus demonstrating catalysed sp3 C-H borylation with new piano stool rhodium indenyl complexes. Irradiation of the monodentate complexes with 400 or 420 nm light confirmed the ready dissociation of C2 H4 and COE ligands, whereas CO complexes were inert. Evidence for C-H bond activation in the alkyl groups of the NHC ligands was obtained.
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Affiliation(s)
- Kieren J. Evans
- Institute of Chemical SciencesHeriot-Watt UniversityEdinburghEH14 4ASUK
| | - Paul A. Morton
- Institute of Chemical SciencesHeriot-Watt UniversityEdinburghEH14 4ASUK
| | - Christian Luz
- Institute of Chemical SciencesHeriot-Watt UniversityEdinburghEH14 4ASUK
| | - Callum Miller
- Institute of Chemical SciencesHeriot-Watt UniversityEdinburghEH14 4ASUK
| | - Olivia Raine
- Institute of Chemical SciencesHeriot-Watt UniversityEdinburghEH14 4ASUK
| | - Jason M. Lynam
- Department of ChemistryUniversity of YorkHeslington, YorkYO10 5DDUK
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5
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Moreno JJ, Espada MF, Maya C, Campos J, López-Serrano J, Macgregor SA, Carmona E. Isomerization of a cationic (η5-C5Me5)Ir(III) complex involving remote C–C and C–H bond formation. Polyhedron 2021. [DOI: 10.1016/j.poly.2021.115363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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6
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Lee BYT, Phillips AD, Hanif M, Tong KKH, Söhnel T, Hartinger CG. Heptadentate, Octadentate, Or Even Nonadentate? Denticity in the Unexpected Formation of an All-Carbon Donor-Atom Ligand in Rh III(Cp*)(Anthracenyl-NHC) Complexes. Inorg Chem 2021; 60:8734-8741. [PMID: 34100283 DOI: 10.1021/acs.inorgchem.1c00711] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Investigations on incorporating an N-flanking anthracenyl moiety to [Rh(Cp*)(NHC)Cl2] complexes surprisingly led to the formation of an intramolecular C-C bond between the Cp* and anthracenyl moieties, with additional auxiliary interactions between the metal and the anthracenyl ring system. In silico modeling supports a reaction mechanism whereby Rh(η4-tetramethylfulvene) intermediates undergo metallocycloaddition and the abstraction of a chlorido ligand, affording unique cationic complexes that feature Rh centers coordinated by a nonadentate ligand with exclusively carbon donor atoms. Some Rh-C interactions were extremely weak but nevertheless exhibited covalent bonding character. These weak Rh-C interactions were readily displaced by stronger electron donors, and the nonadentate ligand reverted to the heptadentate coordination mode observed in the intermediate. As far as we are aware, this study provides the first conclusive evidence of complexes bearing a single nonadentate κ9-coordinating ligand that features only carbon donors bound to a metal center.
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Affiliation(s)
- Betty Y T Lee
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Andrew D Phillips
- School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland
| | - Muhammad Hanif
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Kelvin K H Tong
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Tilo Söhnel
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Christian G Hartinger
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
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7
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van Vuuren E, Malan FP, Landman M. Multidentate NHC complexes of group IX metals featuring carbon-based tethers: Synthesis and applications. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2020.213731] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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8
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Morgan PJ, Hanson-Heine MWD, Thomas HP, Saunders GC, Marr AC, Licence P. C–F Bond Activation of a Perfluorinated Ligand Leading to Nucleophilic Fluorination of an Organic Electrophile. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00176] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Patrick J. Morgan
- GSK Carbon Neutral Laboratory, School of Chemistry, University of Nottingham, Nottingham NG7 2TU, United Kingdom
| | - Magnus W. D. Hanson-Heine
- GSK Carbon Neutral Laboratory, School of Chemistry, University of Nottingham, Nottingham NG7 2TU, United Kingdom
| | - Hayden P. Thomas
- School of Science, University of Waikato, Hamilton 3240, New Zealand
| | | | - Andrew C. Marr
- School of Chemistry and Chemical Engineering, Queen’s University Belfast, David Keir Building, Belfast BT9 5AG, United Kingdom
| | - Peter Licence
- GSK Carbon Neutral Laboratory, School of Chemistry, University of Nottingham, Nottingham NG7 2TU, United Kingdom
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9
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Moreno JJ, Espada MF, Campos J, López-Serrano J, Macgregor SA, Carmona E. Base-Promoted, Remote C-H Activation at a Cationic (η 5-C 5Me 5)Ir(III) Center Involving Reversible C-C Bond Formation of Bound C 5Me 5. J Am Chem Soc 2019; 141:2205-2210. [PMID: 30682245 PMCID: PMC6396953 DOI: 10.1021/jacs.8b11752] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
![]()
C–H
bond activation at cationic [(η5-C5Me5)Ir(PMe2Ar′)] centers is described,
where PMe2Ar′ are the terphenyl phosphine ligands
PMe2ArXyl2 and PMe2ArDipp2. Different pathways are defined for the conversion
of the five-coordinate complexes [(η5-C5Me5)IrCl(PMe2Ar′)]+, 2(Xyl)+ and 2(Dipp)+, into
the corresponding pseudoallyls 3(Xyl)+ and 3(Dipp)+. In the absence of an external Brønsted
base, electrophilic, remote ζ C–H activation takes place,
for which the participation of dicationic species, [(η5-C5Me5)Ir(PMe2Ar′)]2+, is proposed. When NEt3 is present, the PMe2ArDipp2 system is shown to proceed via 4(Dipp)+ as an intermediate en route to the thermodynamic,
isomeric product 3(Dipp)+. This complex interconversion
involves a non-innocent C5Me5 ligand, which
participates in C–H and C–C bond formation and cleavage.
Remarkably, the conversion of 4(Dipp)+ to 3(Dipp)+ also proceeds in the solid state.
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Affiliation(s)
- Juan J Moreno
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA) , Universidad de Sevilla and Consejo Superior de Investigaciones Científicas (CSIC) , Avenida Américo Vespucio 49 , 41092 Sevilla , Spain
| | - María F Espada
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA) , Universidad de Sevilla and Consejo Superior de Investigaciones Científicas (CSIC) , Avenida Américo Vespucio 49 , 41092 Sevilla , Spain
| | - Jesús Campos
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA) , Universidad de Sevilla and Consejo Superior de Investigaciones Científicas (CSIC) , Avenida Américo Vespucio 49 , 41092 Sevilla , Spain
| | - Joaquín López-Serrano
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA) , Universidad de Sevilla and Consejo Superior de Investigaciones Científicas (CSIC) , Avenida Américo Vespucio 49 , 41092 Sevilla , Spain
| | - Stuart A Macgregor
- Institute of Chemical Sciences , Heriot-Watt University , Edinburgh EH14 4AS , United Kingdom
| | - Ernesto Carmona
- Institute of Chemical Sciences , Heriot-Watt University , Edinburgh EH14 4AS , United Kingdom
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10
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Yi X, Liu B, Chen K, Chen W, Chen W. Unbridged Rh(ii)–Rh(ii) complexes of N-heterocyclic carbenes and reactions with O2 to form dirhodium(μ–η1:η1-O2) complexes. Dalton Trans 2019; 48:3835-3839. [DOI: 10.1039/c9dt00421a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Dimeric rhodium(ii) [Rh(L)(CH3CN)]2(PF6)4 and rhodium(iii) peroxide [Rh(L)(PPh3)]2(μ–η1:η1-O2)(PF6)4 and [Rh(L)(PCy3)]2(μ–η1:η1-O2)(PF6)4 (L = bis(N-pyridylimidazolylidenyl)methane) were reported.
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Affiliation(s)
- Xiaofei Yi
- Department of Chemistry
- Zhejiang University
- Hangzhou 310007
- China
| | - Bin Liu
- Zhejiang Province Key Laboratory of Noble Metal Catalytic Materials and Technology
- Hangzhou
- China
| | - Kai Chen
- Department of Chemistry
- Zhejiang University
- Hangzhou 310007
- China
| | - Wei Chen
- Department of Chemistry
- Zhejiang University
- Hangzhou 310007
- China
| | - Wanzhi Chen
- Department of Chemistry
- Zhejiang University
- Hangzhou 310007
- China
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