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Schädle D, Litlabø R, Meermann-Zimmermann M, Thim-Spöring R, Schädle C, Maichle-Mössmer C, Törnroos KW, Anwander R. Rare-Earth-Metal Methyl and Methylidene Complexes Stabilized by Tp R,R'-Scorpionato Ligands─Size Matters. Inorg Chem 2024; 63:9624-9637. [PMID: 38407062 DOI: 10.1021/acs.inorgchem.3c04422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Homoleptic tetramethylaluminates Ln(AlMe4)3 react with KTptBu,Me (TptBu,Me = tris(3-tBu-5-Me-pyrazolyl)borato) to yield rare-earth-metal methylidene complexes (TptBu,Me)Ln(μ3-CH2)[(μ-Me)AlMe2]2 (Ln = La, Ce, Nd). The lanthanum reaction is prone to additional C-H- and B-N-bond activation, affording coproducts La[HB(pzMe,tBu)(pzCMe2,Me)2][(μ-CH2)(μ-Me)AlMe2]2 and [La(μ-pztBu,Me)(AlMe4)2]2 (pztBu,Me = 3-tBu-5-Me-pyrazolato). The protonolysis reaction of Ln(AlMe4)3 and HpztBu,Me provides more efficient access to [Ln(μ-pztBu,Me)(AlMe4)2]2 (Ln = La, Nd). Treatment of Ln(AlMe4)3 with KTpMe,Me led to methylidene complexes (TpMe,Me)Ln(μ3-CH2)[(μ-Me)AlMe2]2 (Ln = Nd, Sm) or bis(tetramethylaluminate) complexes (TpMe,Me)Ln(AlMe4)2 (Ln = Y, Lu). The neodymium reaction generated methine derivative (TpMe,Me)Nd[(μ4-CH)(AlMe2)2(μ-pz,Me,Me)][(μ-Me)AlMe2] as a minor coproduct. The reaction of Ln(GaMe4)3 (Ln = Y, La, Ce, Nd, Sm, Ho) with HTptBu,Me gave methylidene complexes (TptBu,Me)Ln(μ3-CH2)[(μ-Me)GaMe2]2 (Ln = La, Ce, Nd, Sm) and alkyl complexes (TptBu,Me)LnMe[(μ-Me)GaMe3] (Ln = Y, Ho), while competing B-N bond activation reactions produced GaMe2[BH(Me)(μ-pztBu,Me)2] and (TptBu,Me)Ln(η2-pztBu,Me)[(μ-Me)GaMe3] (Ln = Y, Ho). The steric impact of the TpR,Me ligands was examined by cone angle calculations. Rare-earth-metal methylidene complexes (TptBu,Me)Ln(μ3-CH2)[(μ-Me)EMe2]2 (E = Al, Ga) successfully promote carbonyl methylenation reactions upon addition of ketone.
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Affiliation(s)
- Dorothea Schädle
- Institut für Anorganische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Rannveig Litlabø
- Institut für Anorganische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
- Department of Chemistry, University of Bergen, Allégaten 41, 5007 Bergen, Norway
| | - Melanie Meermann-Zimmermann
- Institut für Anorganische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
- Department of Chemistry, University of Bergen, Allégaten 41, 5007 Bergen, Norway
| | - Renita Thim-Spöring
- Institut für Anorganische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Christoph Schädle
- Institut für Anorganische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Cäcilia Maichle-Mössmer
- Institut für Anorganische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Karl W Törnroos
- Department of Chemistry, University of Bergen, Allégaten 41, 5007 Bergen, Norway
| | - Reiner Anwander
- Institut für Anorganische Chemie, Universität Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
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2
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Jiang W, Rajeshkumar T, Guo M, Lin Y, Maron L, Zhang L. Rare-earth metal ethylene and ethyne complexes. Chem Sci 2024; 15:3495-3501. [PMID: 38455028 PMCID: PMC10915835 DOI: 10.1039/d3sc06599e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 01/26/2024] [Indexed: 03/09/2024] Open
Abstract
Guanidinate homometallic rare-earth ethyl complexes [LLn(μ2-η1:η2-Et)(Et)]2 (Ln = Y(1-Y), Lu(1-Lu)) and heterobimetallic rare-earth ethyl complexes LLn(Et)(μ2-η1:η2-Et)(μ2-η1-Et)(AlEt2) (Ln = Y(2-Y), Lu(2-Lu)) have been synthesized by the treatment of LLn(CH2C6H4NMe2-o)2 (L = (PhCH2)2NC(NC6H3iPr2-2,6)2) with different equivalents of AlEt3 in toluene at ambient temperature. Interestingly, the unprecedented rare-earth ethyne complex [LY(μ2-η1-Et)2(AlEt)]2(μ4-η1:η1:η2:η2-C2H2) (3-Y) containing a [C2H2]4- unit was afforded from 2-Y. The formation mechanism study on 3-Y was carried out by DFT calculations. Furthermore, the nature of the bonding of 3-Y was also revealed by NBO analysis. The reactions of LLn(CH2 C6H4NMe2-o)2 (Ln = Y, Lu) with AlEt3 (4 equiv.) in toluene at 50 °C produced firstly the non-Cp rare-earth ethylene complex LY(μ3-η1:η1:η2-C2H4)[(μ2-η1-Et)(AlEt2)(μ2-η1-Et)2(AlEt)] (4-Y), and the Y/Al ethyl complex LY[(μ2-η1-Et)2(AlEt2)]2 (5-Y) as an intermediate of 4-Y was isolated from the reaction of LY(CH2C6H4NMe2-o)2 with AlEt3 (4 equiv.) in toluene at -10 °C.
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Affiliation(s)
- Wen Jiang
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University 2005 Songhu Road, Jiangwan Campus Shanghai 200438 P. R. China
| | | | - Mengyue Guo
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University 2005 Songhu Road, Jiangwan Campus Shanghai 200438 P. R. China
| | - Yuejian Lin
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University 2005 Songhu Road, Jiangwan Campus Shanghai 200438 P. R. China
| | | | - Lixin Zhang
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University 2005 Songhu Road, Jiangwan Campus Shanghai 200438 P. R. China
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3
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Guo D, Rajeshkumar T, Zhu S, Yuan Q, Hong D, Zhou S, Zhu X, Maron L, Wang S. Aryl C-H bond functionalization with diphenyldiazomethane induced by rare-earth metal alkyl complexes. Dalton Trans 2023; 52:11315-11324. [PMID: 37530174 DOI: 10.1039/d3dt01714a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023]
Abstract
The first examples of regioselective aryl ortho-C-H functionalization with diphenyldiazomethane for the construction of Caryl-Nhydrazinato bonds were accomplished via the activation of C-H bonds and the subsequent reaction of diphenyldiazomethane with the RE-Caryl bond. The reactions of rare-earth metal monoalkyl complexes LRE(CH2SiMe3)(THF)2 (L = 2,5-[(2-pyrrolyl)CPh2]2(N-Me-pyrrole)) supported by a neutral N-methylpyrrole anchored dipyrrolyl ligand with 2 equiv. of Ph2CN2 gave irreversibly unprecedented hydrazonato-functionalized imino rare-earth metal complexes LRE(Ph2CNNC6H4-(o-CNHPh) (RE = Y (2a), Lu (2a')) in good yields involving a rather complex process including the interaction of a diazo unit with a RE-Calkyl bond, a β-H elimination, a N-N cleavage, 1,4-hydrogen transfer and the subsequent C-N coupling with another diphenyldiazomethane. More important is that regioselective aryl C-H bond functionalization with diphenyldiazomethane to construct the Caryl-Nhydrazinato bonds can be easily achieved by three-component reactions of rare-earth metal monoalkyl complexes, a wide range of substituted imines (including aldimines, ketimines or analogous 2-phenylpyridine) and diphenyldiazomethane, affording various hydrazonato-functionalized phenyl, thienyl imino or pyridyl rare-earth metal complexes 2b-2j at room temperature. A further study indicated that the substituents on the phenyl ring have a great effect on the reaction pathway and governed the Caryl-Nhydrazinato bond construction. Moreover, the experimental studies show that the formation of the Caryl-Nhydrazinato bonds is thermodynamically facile, which could be realized at room temperature easily.
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Affiliation(s)
- Dianjun Guo
- 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, Anhui 241002, China.
| | - Thayalan Rajeshkumar
- LPCNO, CNRS & INSA, Université Paul Sabatier, 135 Avenue de Rangueil, 31077 Toulouse, France.
| | - Shan Zhu
- 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, Anhui 241002, China.
| | - Qingbing Yuan
- 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, Anhui 241002, China.
| | - Dongjing Hong
- 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, Anhui 241002, China.
| | - Shuangliu Zhou
- 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, Anhui 241002, China.
| | - Xiancui Zhu
- 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, Anhui 241002, China.
| | - Laurent Maron
- LPCNO, CNRS & INSA, Université Paul Sabatier, 135 Avenue de Rangueil, 31077 Toulouse, France.
| | - Shaowu Wang
- 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, Anhui 241002, China.
- Anhui Laboratory of Clean Catalytic Engineering, Anhui Laboratory of Functional Complexes for Materials Chemistry and Application, College of Biological and Chemical Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China.
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4
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Huang Z, Wang R, Sheng T, Zhong X, Wang S, Zhu X, Yuan Q, Wei Y, Zhou S. Transformation of the sp 2 Carbanion to Carbene with Subsequent 1,1-Migratory Insertion and Nucleophilic Substitution in Rare-Earth Metal Chemistry. Inorg Chem 2021; 60:18843-18853. [PMID: 34846129 DOI: 10.1021/acs.inorgchem.1c02589] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The development of Fischer-type electrophilic carbene chemistry with early transition metals has been a great challenge due to the fact that such metals in their high oxidation states lack the d electrons to stabilize the electrophilic carbene. Herein, we disclose the first experimental and theoretical findings of in situ transformation of an sp2 carbanion to a Fischer-type electrophilic carbene with rare-earth metals in their high oxidation state with a d0 electron via electron transfer. The carbene may undergo 1,1-migratory insertion into an adjacent RE-C(sp3) bond, and an unprecedented ring opening of the indole ring of the ligand occurs when the carbenes undergo nucleophilic substitution with a special organolithium reagent o-Me2NC6H4CH2Li. The key to success is the uniquely tailored novel ligand systems featuring a suitable conjugate building block (-C═C-C═N) bearing an sp2 carbanion connected to the rare-earth metal center.
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Affiliation(s)
- Zeming Huang
- 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, Anhui 241000, P. R. China
| | - Ruru Wang
- 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, Anhui 241000, P. R. China
| | - Tian Sheng
- 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, Anhui 241000, P. R. China
| | - Xiangyang Zhong
- 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, Anhui 241000, P. R. China
| | - Shaowu Wang
- 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, Anhui 241000, P. R. China.,Anhui Laboratory of Clean Catalytic Engineering, Anhui Laboratory of Functional Coordinated Complexes for Materials Chemistry and Application, College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, P. R. China.,State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P. R. China
| | - Xiancui Zhu
- 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, Anhui 241000, P. R. China
| | - Qingbing Yuan
- 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, Anhui 241000, P. R. China
| | - Yun Wei
- 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, Anhui 241000, P. R. China
| | - Shuangliu Zhou
- 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, Anhui 241000, P. R. China
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5
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Deng P, Shi X, Gong X, Cheng J. Trinuclear scandium methylidyne complexes stabilized by pentamethylcyclopentadienyl ligands. Chem Commun (Camb) 2021; 57:6436-6439. [PMID: 34095916 DOI: 10.1039/d1cc01645h] [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
The first examples of scandium methylidyne complexes [(Cp*)Sc(μ2-X)]3(μ3-CH) (Cp* = C5Me5; X = Br, Me, OMe), free of Lewis acids, can be achieved in high yields from [(Cp*)ScMe2]2 through a facile route. The chemical and geometrical flexibility to incorporate organic substrates indicates a rich chemistry of complex [(Cp*)Sc(μ2-OMe)]3(μ3-CH).
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Affiliation(s)
- Peng Deng
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, No. 5625, Renmin Street, Changchun 130022, China. and University of Science and Technology of China, Hefei, Anhui 230029, China
| | - Xianghui Shi
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, No. 5625, Renmin Street, Changchun 130022, China.
| | - Xun Gong
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, No. 5625, Renmin Street, Changchun 130022, China. and University of Science and Technology of China, Hefei, Anhui 230029, China
| | - Jianhua Cheng
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, No. 5625, Renmin Street, Changchun 130022, China. and University of Science and Technology of China, Hefei, Anhui 230029, China
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6
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Rad'kova NY, Kovylina TA, Cherkasov AV, Lyssenko KA, Ob'edkov AM, Trifonov AA. Coordination Features of the 1,3,5‐Triazapentadienyl Ligand in Alkyl Complexes of Rare‐Earth Metals. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Natalia Yu. Rad'kova
- Institute of Organometallic Chemistry of Russian Academy of Sciences Tropinina Street 49, GSP-445 603950 Nizhny Novgorod Russia
| | - Tatyana A. Kovylina
- Institute of Organometallic Chemistry of Russian Academy of Sciences Tropinina Street 49, GSP-445 603950 Nizhny Novgorod Russia
| | - Anton V. Cherkasov
- Institute of Organometallic Chemistry of Russian Academy of Sciences Tropinina Street 49, GSP-445 603950 Nizhny Novgorod Russia
| | - Konstantin A. Lyssenko
- Institute of Organoelement Compounds of Russian Academy of Sciences Vavilova Street 28 119334 Moscow Russia
- M.V. Lomonosov Moscow State University Chemistry Department Leninskie Gory 119991 Moscow Russia
| | - Anatoly M. Ob'edkov
- Institute of Organometallic Chemistry of Russian Academy of Sciences Tropinina Street 49, GSP-445 603950 Nizhny Novgorod Russia
| | - Alexander A. Trifonov
- Institute of Organometallic Chemistry of Russian Academy of Sciences Tropinina Street 49, GSP-445 603950 Nizhny Novgorod Russia
- Institute of Organoelement Compounds of Russian Academy of Sciences Vavilova Street 28 119334 Moscow Russia
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7
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Xu C, Ye Z, Xiang L, Yang S, Peng Q, Leng X, Chen Y. Insertion of Metal‐Substituted Silylene into Naphthalene's Aromatic Ring and Subsequent Rearrangement for Silaspiro‐Benzocycloheptenyl and Cyclobutenosilaindan Derivatives. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202012649] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Cheng Xu
- State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 P. R. China
| | - Zhen Ye
- State Key Laboratory of Elemento-Organic Chemistry College of Chemistry Nankai University 94 Weijin Road Tianjin 300071 P. R. China
| | - Li Xiang
- State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 P. R. China
| | - Shuhan Yang
- State Key Laboratory of Elemento-Organic Chemistry College of Chemistry Nankai University 94 Weijin Road Tianjin 300071 P. R. China
| | - Qian Peng
- State Key Laboratory of Elemento-Organic Chemistry College of Chemistry Nankai University 94 Weijin Road Tianjin 300071 P. R. China
| | - Xuebing Leng
- State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 P. R. China
| | - Yaofeng Chen
- State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 P. R. China
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8
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Xu C, Ye Z, Xiang L, Yang S, Peng Q, Leng X, Chen Y. Insertion of Metal-Substituted Silylene into Naphthalene's Aromatic Ring and Subsequent Rearrangement for Silaspiro-Benzocycloheptenyl and Cyclobutenosilaindan Derivatives. Angew Chem Int Ed Engl 2020; 60:3189-3195. [PMID: 33108013 DOI: 10.1002/anie.202012649] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Indexed: 11/11/2022]
Abstract
Synthesis of silacycle compounds are of fundamental and application importance. Herein we report the first example of insertion of metal-substituted silylene fragment into naphthalene's aromatic ring. More significantly, this insertion is followed by interesting rearrangements to yield silaspiro-benzocycloheptenyl and cyclobutenosilaindan derivatives. The formation of cyclobutenosilaindan derivative includes the C-C bond cleavage and 4π electrocyclization steps; the formation of silaspiro-benzocycloheptenyl derivative is more complicated, including the C-C bond cleavage, reversible 4π electrocyclization, C-H bond activation and C-Si bond cleavage. DFT investigations were carried out to shed light on the mechanistic aspects of these two rearrangements. The formed cyclobutenosilaindan potassium can readily react with PhOH, MeOTf, EtOTf, PhCH2 Cl or PhCOCl at room temperature to afford the hydrogen, alkyl, benzyl or benzoyl substituted cyclobutenosilaindans in high yields.
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Affiliation(s)
- Cheng Xu
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
| | - Zhen Ye
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, P. R. China
| | - Li Xiang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
| | - Shuhan Yang
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, P. R. China
| | - Qian Peng
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, P. R. China
| | - Xuebing Leng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
| | - Yaofeng Chen
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
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9
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Zhang Y, Wu B, Zhong M, Zhang WX, Xi Z. Cyclic Bis-alkylidene Complexes of Titanium and Zirconium: Synthesis, Characterization, and Reaction. Chemistry 2020; 26:16472-16479. [PMID: 32875626 DOI: 10.1002/chem.202003240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/29/2020] [Indexed: 11/06/2022]
Abstract
Transition-metal alkylidenes have exhibited wide applications in organometallic chemistry and synthetic organic chemistry, however, cyclic Schrock-carbene-like bis-alkylidenes of group 4 metals with a four-electron donor from an alkylidene have not been reported. Herein, the synthesis and characterization of five-membered cyclic bis-alkylidenes of titanium (4 a,b) and zirconium (5 a,b) are reported, as the first well-defined group 4 metallacyclopentatrienes, by two-electron reduction of their corresponding titana- and zirconacyclopentadienes. DFT analyses of 4 a show a four-electron donor (σ-donation and π-donation) from an alkylidene carbon to the metal center. The reaction of 4 a with N,N'-diisopropylcarbodiimide (DIC) leads to the [2+2]-cycloaddition product 6. Compound 4 a reacted with CO, affording the oxycyclopentadienyl titanium complex 7. These reactivities demonstrate the multiple metal-carbon bond character. The reactions of 4 a or 5 a with cyclooctatetraene (COT) or azobenzene afforded sandwich titanium complex 8 or diphenylhydrazine-coordinated zirconacyclopentadiene 9, respectively, which exhibit two-electron reductive ability.
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Affiliation(s)
- Yongliang Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P.R. China
| | - Botao Wu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P.R. China
| | - Mingdong Zhong
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P.R. China
| | - Wen-Xiong Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P.R. China
| | - Zhenfeng Xi
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P.R. China.,State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Shanghai, 200032, P.R. China
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10
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Casey KC, Appiah JK, Robinson JR. Low-Symmetry β-Diketimine Aryloxide Rare-Earth Complexes: Flexible, Reactive, and Selective. Inorg Chem 2020; 59:14827-14837. [PMID: 32986427 DOI: 10.1021/acs.inorgchem.0c02170] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We report the synthesis, characterization, and reactivity of a new low-symmetry β-diketimine featuring a pendant amino(methyl)phenol donor and its corresponding heteroleptic rare-earth (RE) complexes. This includes the first structurally characterized examples of alcoholysis and insertion from an isolated REIII amide in a β-diketimine framework. The flexible methylene linkage leads to REIII complexes with tunable dynamic solution behavior that defines their stoichiometric and catalytic reactivity. The addition of a strong neutral donor ligand, tricyclohexylphosphine oxide, suppresses a prevalent catalyst degradation pathway (base-promoted elimination) and dramatically enhances the catalyst performance in the stereospecific ring-opening polymerization of rac-β-butyrolactone. Our results further demonstrate the importance of ligand reorganization in the stoichiometric and catalytic activity of REIII ions.
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Affiliation(s)
- Kerry C Casey
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, United States
| | - Jude K Appiah
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, United States
| | - Jerome R Robinson
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, United States
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11
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Guo L, Zhou M, Guo H, Xu W, Li Z. Dilithium complex incorporating phenyl bridged neutral pyrrolyl-arylamide ligand: Synthesis, characterization, reaction, and catalytic activity. INORG CHEM COMMUN 2020. [DOI: 10.1016/j.inoche.2020.108036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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12
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Jiang W, Zhang L, Zhang L. Synthesis, Structure, and Reactivity of Monoguanidinate Rare‐Earth Metal Aminobenzyl Enolate Complexes. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000148] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Wen Jiang
- Key Laboratory of Functional Molecular Solids Ministry of Education Anhui Laboratory of Molecule‐Based Materials, College of Chemistry and Materials Science Anhui Normal University 241000 Wuhu Anhui China
- Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Jiangwan Campus Fudan University 200438 Shanghai China
| | - Li‐Jun Zhang
- Key Laboratory of Functional Molecular Solids Ministry of Education Anhui Laboratory of Molecule‐Based Materials, College of Chemistry and Materials Science Anhui Normal University 241000 Wuhu Anhui China
| | - Li‐Xin Zhang
- Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Jiangwan Campus Fudan University 200438 Shanghai China
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Zheng Y, Cao CS, Ma W, Chen T, Wu B, Yu C, Huang Z, Yin J, Hu HS, Li J, Zhang WX, Xi Z. 2-Butene Tetraanion Bridged Dinuclear Samarium(III) Complexes via Sm(II)-Mediated Reduction of Electron-Rich Olefins. J Am Chem Soc 2020; 142:10705-10714. [PMID: 32408744 DOI: 10.1021/jacs.0c01690] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
While reduction reactions are ubiquitous in chemistry, it is very challenging to further reduce electron-rich compounds, especially the anionic ones. In this work, the reduction of 1,3-butadienyl dianion, the anionic conjugated olefin, has been realized by divalent rare-earth metal compounds (SmI2), resulting in the formation of novel 2-butene tetraanion bridged disamarium(III) complexes. Density functional theory (DFT) analyses reveal two features: (i) the single electron transfer (SET) from 4f atomic orbitals (AOs) of each Sm center to the antibonding π*-orbitals of 1,3-butadienyl dianion is feasible and the new HOMO formed by the bonding interaction between Sm 5d orbitals (AOs) and the π*-orbitals of 1,3-butadienyl dianion can accept favorably 2e- from 4f AOs of Sm(II); (ii) the 2-butene tetraanionic ligand serves as a unique 10e- donating system, in which 4e- act as two σ-donation bonding interactions while the rest 6e- as three π-donation bonding interactions. The disamarium(III) complexes represent a unique class of the bridged bis-alkylidene rare-earth organometallic complexes. The ligand-based reductive reactivity of 2-butene tetraanion bridged disamarium(III) complexes demonstrates that 2-butene tetraanionic ligand serves as a 3e- reductant toward cyclooctatetraene (COT) to provide doubly COT-supported disamarabutadiene complexes. The reaction of the disamarium(III) complexes with Cp*Li produces the doubly Cp*-coordinated Sm(III) complexes via salt metathesis. In addition, the reaction with Mo(CO)6 affords the oxycyclopentadienyl dinuclear complex via CO insertion.
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Affiliation(s)
- Yu Zheng
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Chang-Su Cao
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
| | - Wangyang Ma
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Tianyang Chen
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Botao Wu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Chao Yu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Zhe Huang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Jianhao Yin
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Han-Shi Hu
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
| | - Jun Li
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China.,Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Wen-Xiong Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Zhenfeng Xi
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
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14
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Zatsepin P, Lee E, Gu J, Gau MR, Carroll PJ, Baik MH, Mindiola DJ. Tebbe-like and Phosphonioalkylidene and -alkylidyne Complexes of Scandium. J Am Chem Soc 2020; 142:10143-10152. [DOI: 10.1021/jacs.0c02742] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pavel Zatsepin
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Eunji Lee
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), and Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Jun Gu
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Michael R. Gau
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Patrick J. Carroll
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Mu-Hyun Baik
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), and Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Daniel J. Mindiola
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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15
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Su W, Pan S, Sun X, Zhao L, Frenking G, Zhu C. Cerium-carbon dative interactions supported by carbodiphosphorane. Dalton Trans 2019; 48:16108-16114. [PMID: 31620743 DOI: 10.1039/c9dt03770e] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A set of complexes containing dative interactions between a rare-earth metal and carbon are reported. Complex 2, Br3Ce(CDP)(THF), with a Ce←C bond was synthesized by the reaction of CeBr3 with a carbon(0) ligand, carbodiphosphorane (CDP). More significantly, a trivalent cerium complex 3, [BrCe(CDP)2](BPh4)2, with two σ dative interactions C→Ce←C was also isolated, which represents an unusual example of two dative interactions formed with the same atom in a molecule. Furthermore, π donation by the second lone-pair electrons of the CDP ligand is rather weak. Single-crystal X-ray diffraction shows that the Ce-C bond lengths in these complexes are comparable with those in cerium(iii)-carbene species. Density functional theory calculations support the dative interaction formation in these complexes and the strength of σ-donation in 3 is stronger than that in 2.
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Affiliation(s)
- Wei Su
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
| | - Sudip Pan
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China.
| | - Xiong Sun
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
| | - Lili Zhao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China.
| | - Gernot Frenking
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China. and Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, Marburg 35032, Germany. and Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Euskadi, Spain
| | - Congqing Zhu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
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16
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Kurogi T, Chu J, Chen Y, Mindiola DJ. Neutral and Anionic Monomeric Zirconium Imides Prepared via Selective C=N Bond Cleavage of a Multidentate and Sterically Demanding β‐Diketiminato Ligand. Chem Asian J 2019; 14:2629-2638. [DOI: 10.1002/asia.201900451] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 05/13/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Takashi Kurogi
- Department of ChemistryUniversity of Pennsylvania 231 South 34th Street Philadelphia PA 19104 USA
| | - Jiaxiang Chu
- State Key Laboratory of Organometallic ChemistryShanghai Institute of Organic Chemistry, Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 P. R. China
| | - Yaofeng Chen
- State Key Laboratory of Organometallic ChemistryShanghai Institute of Organic Chemistry, Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 P. R. China
| | - Daniel J. Mindiola
- Department of ChemistryUniversity of Pennsylvania 231 South 34th Street Philadelphia PA 19104 USA
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17
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Fustier-Boutignon M, Nebra N, Mézailles N. Geminal Dianions Stabilized by Main Group Elements. Chem Rev 2019; 119:8555-8700. [PMID: 31194516 DOI: 10.1021/acs.chemrev.8b00802] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
This review is dedicated to the chemistry of stable and isolable species that bear two lone pairs at the same C center, i.e., geminal dianions, stabilized by main group elements. Three cases can thus be considered: the geminal-dilithio derivative, for which the two substituents at C are neutral, the yldiide derivatives, for which one substituent is neutral while the other is charged, and finally the geminal bisylides, for which the two substituents are positively charged. In this review, the syntheses and electronic structures of the geminal dianions are presented, followed by the studies dedicated to their reactivity toward organic substrates and finally to their coordination chemistry and applications.
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Affiliation(s)
- Marie Fustier-Boutignon
- UPS, CNRS, LHFA UMR 5069 , Université de Toulouse , 118 Route de Narbonne , 31062 Toulouse , France
| | - Noel Nebra
- UPS, CNRS, LHFA UMR 5069 , Université de Toulouse , 118 Route de Narbonne , 31062 Toulouse , France
| | - Nicolas Mézailles
- UPS, CNRS, LHFA UMR 5069 , Université de Toulouse , 118 Route de Narbonne , 31062 Toulouse , France
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18
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Wang C, Mao W, Xiang L, Yang Y, Fang J, Maron L, Leng X, Chen Y. Monomeric Rare-Earth Metal Silyl-Thiophosphinoyl-Alkylidene Complexes: Synthesis, Structure, and Reactivity. Chemistry 2018; 24:13903-13917. [DOI: 10.1002/chem.201802791] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Chen Wang
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P.R. China
| | - Weiqing Mao
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P.R. China
| | - Li Xiang
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P.R. China
| | - Yan Yang
- Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization; Gansu Province School of Chemistry and Chemical Engineering; Lanzhou University; Lanzhou 730000 P.R. China
| | - Jian Fang
- Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization; Gansu Province School of Chemistry and Chemical Engineering; Lanzhou University; Lanzhou 730000 P.R. China
| | - Laurent Maron
- LPCNO, CNRS, & INSA; Université Paul Sabatier; 135 Avenue de Rangueil 31077 Toulouse France
| | - Xuebing Leng
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P.R. China
| | - Yaofeng Chen
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P.R. China
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19
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Mao W, Xiang L, Lamsfus CA, Maron L, Leng X, Chen Y. Are Sc-C and Sc-P Bonds Reactive in Scandium Phosphinoalkylidene Complex? Insights on a Versatile Reactivity. CHINESE J CHEM 2018. [DOI: 10.1002/cjoc.201800253] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Weiqing Mao
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road; Shanghai 200032 China
| | - Li Xiang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road; Shanghai 200032 China
| | - Carlos Alvarez Lamsfus
- LPCNO, CNRS & INSA, Université Paul Sabatier, 135 Avenue de Rangueil; 31077 Toulouse France
| | - Laurent Maron
- LPCNO, CNRS & INSA, Université Paul Sabatier, 135 Avenue de Rangueil; 31077 Toulouse France
| | - Xuebing Leng
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road; Shanghai 200032 China
| | - Yaofeng Chen
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road; Shanghai 200032 China
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20
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Dianionic Carbon-Bridged Scandium-Copper/Silver Heterobimetallic Complexes: Synthesis, Bonding, and Reactivity. Chemistry 2018; 24:5637-5643. [DOI: 10.1002/chem.201706147] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Indexed: 11/07/2022]
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21
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Abstract
Research into transition metal complexes bearing multiply bonded main-group ligands has developed into a thriving and fruitful field over the past half century. These complexes, featuring terminal M═E/M≡E (M = transition metal; E = main-group element) multiple bonds, exhibit unique structural properties as well as rich reactivity, which render them attractive targets for inorganic/organometallic chemists as well as indispensable tools for organic/catalytic chemists. This fact has been highlighted by their widespread applications in organic synthesis, for example, as olefin metathesis catalysts. In the ongoing renaissance of transition metal-ligand multiple-bonding chemistry, there have been reports of M═E/M≡E interactions for the majority of the metallic elements of the periodic table, even some actinide metals. In stark contrast, the largest subgroup of the periodic table, rare-earth metals (Ln = Sc, Y, and lanthanides), have been excluded from this upsurge. Indeed, the synthesis of terminal Ln═E/Ln≡E multiple-bonding species lagged behind that of the transition metal and actinide congeners for decades. Although these species had been pursued since the discovery of a rare-earth metal bridging imide in 1991, such a terminal (nonpincer/bridging hapticities) Ln═E/Ln≡E bond species was not obtained until 2010. The scarcity is mainly attributed to the energy mismatch between the frontier orbitals of the metal and the ligand atoms. This renders the putative terminal Ln═E/Ln≡E bonds extremely reactive, thus resulting in the formation of aggregates and/or reaction with the ligand/environment, quenching the multiple-bond character. In 2010, the stalemate was broken by the isolation and structural characterization of the first rare-earth metal terminal imide-a scandium terminal imide-by our group. The double-bond character of the Sc═N bond was unequivocally confirmed by single-crystal X-ray diffraction. Theoretical investigations revealed the presence of two p-d π bonds between the scandium ion and the nitrogen atom of the imido ligand and showed that the dianionic [NR]2- imido ligand acts as a 2σ,4π electron donor. Subsequent studies of the scandium terminal imides revealed highly versatile and intriguing reactivity of the Sc═N bond. This included cycloaddition toward various unsaturated bonds, C-H/Si-H/B-H bond activations and catalytic hydrosilylation, dehydrofluorination of fluoro-substituted benzenes/alkanes, CO2 and H2 activations, activation of elemental selenium, coordination with other transition metal halides, etc. Since our initial success in 2010, and with contributions from us and across the community, this young, vibrant research field has rapidly flourished into one of the most active frontiers of rare-earth metal chemistry. The prospect of extending Ln═N chemistry to other rare-earth metals and/or different metal oxidation states, as well as exploiting their stoichiometric and catalytic reactivities, continues to attract research effort. Herein we present an account of our investigations into scandium terminal imido chemistry as a timely summary, in the hope that our studies will be of interest to this readership.
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Affiliation(s)
- Erli Lu
- State Key Laboratory of Organometallic
Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
| | - Jiaxiang Chu
- State Key Laboratory of Organometallic
Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
| | - Yaofeng Chen
- State Key Laboratory of Organometallic
Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
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22
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The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2016. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2017.09.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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23
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Zhu X, Li Y, Guo D, Wang S, Wei Y, Zhou S. Versatile reactivities of rare-earth metal dialkyl complexes supported by a neutral pyrrolyl-functionalized β-diketiminato ligand. Dalton Trans 2018; 47:3947-3957. [DOI: 10.1039/c7dt04410k] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first unprecedented examples of S-β-diketiminato species were disclosed in the reactions of rare-earth dialkyl complexes with S8.
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Affiliation(s)
- Xiancui Zhu
- Key Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Yang Li
- Key Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Dianjun Guo
- Key Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Shaowu Wang
- Key Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Yun Wei
- Key Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Shuangliu Zhou
- Key Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
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24
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Mao W, Xiang L, Maron L, Leng X, Chen Y. Nonchelated Phosphoniomethylidene Complexes of Scandium and Lutetium. J Am Chem Soc 2017; 139:17759-17762. [DOI: 10.1021/jacs.7b11097] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Weiqing Mao
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
| | - Li Xiang
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
| | - Laurent Maron
- LPCNO, CNRS & INSA, Université Paul Sabatier, 135 Avenue de Rangueil, 31077 Toulouse, France
| | - Xuebing Leng
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
| | - Yaofeng Chen
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. China
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25
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Han X, Xiang L, Lamsfus CA, Mao W, Lu E, Maron L, Leng X, Chen Y. Synthesis and Reactivity of a Scandium Terminal Hydride: H2
Activation by a Scandium Terminal Imido Complex. Chemistry 2017; 23:14728-14732. [DOI: 10.1002/chem.201703905] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Xianghao Han
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P. R. China
| | - Li Xiang
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P. R. China
| | - Carlos A. Lamsfus
- LPCNO, CNRS & INSA; Université Paul Sabatier; 135 Avenue de Rangueil 31077 Toulouse France
| | - Weiqing Mao
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P. R. China
| | - Erli Lu
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P. R. China
| | - Laurent Maron
- LPCNO, CNRS & INSA; Université Paul Sabatier; 135 Avenue de Rangueil 31077 Toulouse France
| | - Xuebing Leng
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P. R. China
| | - Yaofeng Chen
- State Key Laboratory of Organometallic Chemistry; Shanghai Institute of Organic Chemistry; University of Chinese Academy of Sciences; Chinese Academy of Sciences; 345 Lingling Road Shanghai 200032 P. R. China
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26
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Rare-earth metal complexes of β-diketiminato ligands bearing pendant nitrogen or oxygen donors. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2016.12.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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27
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Ma W, Yu C, Chi Y, Chen T, Wang L, Yin J, Wei B, Xu L, Zhang WX, Xi Z. Formation and ligand-based reductive chemistry of bridged bis-alkylidene scandium(iii) complexes. Chem Sci 2017; 8:6852-6856. [PMID: 29147510 PMCID: PMC5632790 DOI: 10.1039/c7sc02018j] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 07/26/2017] [Indexed: 11/21/2022] Open
Abstract
Bridged bis-alkylidene Sc(iii) complexes featuring a 2-butene-1,1,4,4-tetraanion are synthesized and show unexpected ligand-based two-electron or four-electron reduction reactivity towards different oxidants.
The chemistry of rare-earth carbene and alkylidene complexes including their synthesis, structure and reaction is a challenging issue because of their high reactivity (or instability) and the lack of synthetic methods. In this work, we report the first synthesis of the bridged bis-alkylidene complexes which feature a 2-butene-1,1,4,4-tetraanion and four Sc–C(sp3) bonds by the reaction of 1,4-dilithio-1,3-butadienes with ScCl3. This reaction proceeds via two key intermediates: an isolable scandacyclopentadiene and a proposed scandacyclopropene. The scandacyclopentadiene undergoes β,β′-C–C bond cleavage to generate the scandacyclopropene, which then dimerizes to afford the bridged bis-alkylidene complex via a cooperative double metathesis reaction. Reaction chemistry study of the bridged bis-alkylidene complex reveals their ligand-based reduction reactivity towards different oxidants such as hexachloroethane, disulfide and cyclooctatetraene.
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Affiliation(s)
- Wangyang Ma
- Beijing National Laboratory for Molecular Sciences , MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering , College of Chemistry , Peking University , Beijing 100871 , China .
| | - Chao Yu
- Beijing National Laboratory for Molecular Sciences , MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering , College of Chemistry , Peking University , Beijing 100871 , China .
| | - Yue Chi
- Beijing National Laboratory for Molecular Sciences , MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering , College of Chemistry , Peking University , Beijing 100871 , China .
| | - Tianyang Chen
- Beijing National Laboratory for Molecular Sciences , MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering , College of Chemistry , Peking University , Beijing 100871 , China .
| | - Lianjun Wang
- Beijing National Laboratory for Molecular Sciences , MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering , College of Chemistry , Peking University , Beijing 100871 , China . .,School of Chemistry and Chemical Engineering , Hunan Institute of Engineering , Xiangtan , 411104 , China
| | - Jianhao Yin
- Beijing National Laboratory for Molecular Sciences , MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering , College of Chemistry , Peking University , Beijing 100871 , China .
| | - Baosheng Wei
- Beijing National Laboratory for Molecular Sciences , MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering , College of Chemistry , Peking University , Beijing 100871 , China .
| | - Ling Xu
- Beijing National Laboratory for Molecular Sciences , MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering , College of Chemistry , Peking University , Beijing 100871 , China .
| | - Wen-Xiong Zhang
- Beijing National Laboratory for Molecular Sciences , MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering , College of Chemistry , Peking University , Beijing 100871 , China . .,State Key Laboratory of Elemento-Organic Chemistry , Nankai University , Tianjin , 300071 , China
| | - Zhenfeng Xi
- Beijing National Laboratory for Molecular Sciences , MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering , College of Chemistry , Peking University , Beijing 100871 , China .
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28
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Edelmann FT. Lanthanides and actinides: Annual survey of their organometallic chemistry covering the year 2016. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2017.02.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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29
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Mao W, Xiang L, Alvarez Lamsfus C, Maron L, Leng X, Chen Y. Highly Reactive Scandium Phosphinoalkylidene Complex: C-H and H-H Bonds Activation. J Am Chem Soc 2017; 139:1081-1084. [PMID: 28068074 DOI: 10.1021/jacs.6b13081] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The first scandium phosphinoalkylidene complex was synthesized and structurally characterized. The complex has the shortest Sc-C bond lengths reported to date (2.089(3) Å). DFT calculations reveal the presence of a three center π interaction in the complex. This scandium phosphinoalkylidene complex undergoes intermolecular C-H bond activation of pyridine, 4-dimethylamino pyridine and 1,3-dimethylpyrazole at room temperature. Furthermore, the complex rapidly activates H2 under mild conditions. DFT calculations also demonstrate that the C-H activation of 1,3-dimethylpyrazole is selective for thermodynamic reasons and the relatively slow reaction is due to the need of fully breaking the chelating effect of the phosphino group to undergo the reaction whereas this is not the case for H2.
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Affiliation(s)
- Weiqing Mao
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, P. R. China
| | - Li Xiang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, P. R. China
| | - Carlos Alvarez Lamsfus
- LPCNO, CNRS & INSA, Université Paul Sabatier , 135 Avenue de Rangueil, 31077 Toulouse, France
| | - Laurent Maron
- LPCNO, CNRS & INSA, Université Paul Sabatier , 135 Avenue de Rangueil, 31077 Toulouse, France
| | - Xuebing Leng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, P. R. China
| | - Yaofeng Chen
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, P. R. China
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30
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Miao H, Wang S, Zhu X, Zhou S, Wei Y, Yuan Q, Mu X. Synthesis, characterization and catalytic activity of rare-earth metal amides incorporating cyclohexyl bridged bis(β-diketiminato) ligands. RSC Adv 2017. [DOI: 10.1039/c7ra07565k] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The bridged bis(β-diketiminato) ligands supported rare-earth amides exhibited high catalytic activity towards the hydrophosphination of β-nitroalkene and α,β-unsaturated carbonyl derivatives with an excellent regioselectivity.
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Affiliation(s)
- Hui Miao
- Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Shaowu Wang
- Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Xiancui Zhu
- Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Shuangliu Zhou
- Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Yun Wei
- Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Qingbing Yuan
- Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
| | - Xiaolong Mu
- Laboratory of Functional Molecular Solids
- Ministry of Education
- Anhui Laboratory of Molecule-Based Materials
- College of Chemistry and Materials Science
- Anhui Normal University
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31
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Levine DS, Tilley TD, Andersen RA. Evidence for the Existence of Group 3 Terminal Methylidene Complexes. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00394] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daniel S. Levine
- Department
of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron
Road, Berkeley, California 94720, United States
| | - T. Don Tilley
- Department
of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron
Road, Berkeley, California 94720, United States
| | - Richard A. Andersen
- Department
of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron
Road, Berkeley, California 94720, United States
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32
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Li T, Zhang G, Guo J, Wang S, Leng X, Chen Y. Tris(pyrazolyl)methanide Complexes of Trivalent Rare-Earth Metals. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00166] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Tengfei Li
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of
Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, People’s Republic of China
| | - Guangchao Zhang
- 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, Anhui 241000, People’s Republic of China
| | - Jingjing Guo
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of
Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, People’s Republic of China
| | - Shaowu Wang
- 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, Anhui 241000, People’s Republic of China
| | - Xuebing Leng
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of
Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, People’s Republic of China
| | - Yaofeng Chen
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of
Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, People’s Republic of China
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33
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Hong J, Li Z, Chen Z, Weng L, Zhou X, Zhang L. Small molecule activation by mixed methyl/methylidene rare earth metal complexes. Dalton Trans 2016; 45:6641-9. [DOI: 10.1039/c6dt00314a] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Diverse reactivity patterns of mixed tetramethyl/methylidene rare-earth complexes bearing bulky benzamidinate coligands with PhCN, alkynes, and CS2 have been established and fully characterized.
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Affiliation(s)
- Jianquan Hong
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
| | - Zhenhua Li
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
| | - Zhening Chen
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
| | - Linhong Weng
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
| | - Xigeng Zhou
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
| | - Lixin Zhang
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
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