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Provinciali G, Bortoluzzi M, Funaioli T, Zacchini S, Campanella B, Pampaloni G, Marchetti F. Tetrasubstituted Selenophenes from the Stepwise Assembly of Molecular Fragments on a Diiron Frame and Final Cleavage of a Bridging Alkylidene. Inorg Chem 2020; 59:17497-17508. [PMID: 33205950 PMCID: PMC8016200 DOI: 10.1021/acs.inorgchem.0c02748] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
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A series
of 2,3-dicarboxylato-5-acetyl-4-aminoselenophenes, 5a–j, was obtained via the uncommon assembly
of building blocks on a diiron platform, starting from commercial
[Fe2Cp2(CO)4] through the stepwise
formation of diiron complexes [2a–d]CF3SO3, 3a–d, and 4a–j. The selenophene-substituted
bridging alkylidene ligand in 4a–j is removed from coordination upon treatment with water in air under
mild conditions (ambient temperature in most cases), affording 5a–j in good to excellent yields. This
process is highly selective and is accompanied by the disruption of
the organometallic scaffold: cyclopentadiene (CpH) and lepidocrocite
(γ-FeO(OH)) were identified by NMR and Raman analyses at the
end of one representative reaction. The straightforward cleavage of
the linkage between a bridging Fischer alkylidene and two (or more)
metal centers, as observed here, is an unprecedented reaction in organometallic
chemistry: in the present case, the carbene function is converted
to a ketone which is incorporated into the organic product. DFT calculations
and electrochemical experiments were carried out to give insight into
the release of the selenophene-alkylidene ligand. Compounds 5a–j were fully characterized by elemental
analysis, mass spectrometry, IR, and multinuclear NMR spectroscopy
and by X-ray diffraction and cyclic voltammetry in one case. Metal−metal cooperativity in action!
Different fragments
are combined on the {Fe2Cp2(CO)2}
skeleton to give highly functionalized selenophene ligands, linked
to the iron centers through a bridging alkylidene, which is easily
removed from coordination by exposure to air/water in ethereal solution.
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Affiliation(s)
- Giacomo Provinciali
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, I-56124 Pisa, Italy
| | - Marco Bortoluzzi
- Dipartimento di Scienze Molecolari e Nanosistemi, Ca' Foscari Università di Venezia, Via Torino 155, I-30170 Mestre (VE), Italy
| | - Tiziana Funaioli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, I-56124 Pisa, Italy
| | - Stefano Zacchini
- Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna, Viale Risorgimento 4, I-40136 Bologna, Italy
| | - Beatrice Campanella
- Istituto di Chimica dei Composti Organometallici, Consiglio Nazionale delle Ricerche, Via G. Moruzzi 1, I-56124 Pisa, Italy
| | - Guido Pampaloni
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, I-56124 Pisa, Italy
| | - Fabio Marchetti
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, I-56124 Pisa, Italy
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Bartalucci N, Bortoluzzi M, Pampaloni G, Pinzino C, Zacchini S, Marchetti F. Stable coordination complexes of α-diimines with Nb(v) and Ta(v) halides. Dalton Trans 2018; 47:3346-3355. [DOI: 10.1039/c8dt00122g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Uncommon coordination compounds of high valent transition metal halides with N-aryl α-diimines have been obtained, without the need for reducing agents to quench the activation power of the metal centre.
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Affiliation(s)
- Niccolò Bartalucci
- Università di Pisa
- Dipartimento di Chimica e Chimica Industriale
- I-56124 Pisa
- Italy
- CIRCC
| | - Marco Bortoluzzi
- CIRCC
- I-70126 Bari
- Italy
- Università Ca’ Foscari Venezia
- Dipartimento di Scienze Molecolari e Nanosistemi
| | - Guido Pampaloni
- Università di Pisa
- Dipartimento di Chimica e Chimica Industriale
- I-56124 Pisa
- Italy
- CIRCC
| | | | - Stefano Zacchini
- CIRCC
- I-70126 Bari
- Italy
- Università di Bologna
- Dipartimento di Chimica Industriale “Toso Montanari”
| | - Fabio Marchetti
- Università di Pisa
- Dipartimento di Chimica e Chimica Industriale
- I-56124 Pisa
- Italy
- CIRCC
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3
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Li J, Zhao C, Liu J, Huang H, Wang F, Xu X, Cui C. Activation of Ene-Diamido Samarium Methoxide with Hydrosilane for Selectively Catalytic Hydrosilylation of Alkenes and Polymerization of Styrene: an Experimental and Theoretical Mechanistic Study. Inorg Chem 2016; 55:9105-11. [DOI: 10.1021/acs.inorgchem.6b01670] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jianfeng Li
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Chaoyue Zhao
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Jinxi Liu
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Hanmin Huang
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Fengxin Wang
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Xiufang Xu
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Chunming Cui
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300071, P. R. China
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4
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Bortoluzzi M, Ferretti E, Marchetti F, Pampaloni G, Pinzino C, Zacchini S. Coordination Compounds of Niobium(IV) Oxide Dihalides Including the Synthesis and the Crystallographic Characterization of NHC Complexes. Inorg Chem 2016; 55:4173-82. [PMID: 27082642 DOI: 10.1021/acs.inorgchem.5b02888] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The 1:1 molar reactions of NbOX3 with SnBu3H, in toluene at 0 °C in the presence of oxygen/nitrogen donors, resulted in the formation of NbOX2L2 (X = Cl, L2 = dme, 2a; X = Br, L2 = dme, 2b; X = Cl, L = thf, 2c; X = Cl, L = NCMe, 2d; dme = 1,2-dimethoxyethane, thf = tetrahydrofuran), in good yields. The 1:2 reactions of freshly prepared 2d and 2b with the bulky NHC ligands 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene, Imes, and 1,3-bis(2,6-dimethylphenyl)imidazol-2-ylidene, Ixyl, respectively, afforded the complexes NbOCl2(Imes)2, 3, and NbOBr2(Ixyl)2, 4, in 50-60% yields. The reactions of 2b with NaOR, in tetrahydrofuran, gave NbOCl(OR) (R = Ph, 5; R = Me, 6) in about 60% yields. All the products were characterized by analytical and spectroscopic techniques; moreover DFT calculations were carried out in order to shed light on synthetic and structural features. Compounds 3 and 4, whose molecular structures have been ascertained by X-ray diffraction, represent very rare examples of crystallographically characterized niobium-NHC systems.
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Affiliation(s)
- Marco Bortoluzzi
- Dipartimento di Scienze Molecolari e Nanosistemi, Università di Venezia Ca' Foscari , Via Torino 155, I-30170 Mestre, Venice, Italy
| | - Eleonora Ferretti
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa , Via G. Moruzzi 13, I-56124 Pisa, Italy
| | - Fabio Marchetti
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa , Via G. Moruzzi 13, I-56124 Pisa, Italy
| | - Guido Pampaloni
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa , Via G. Moruzzi 13, I-56124 Pisa, Italy
| | - Calogero Pinzino
- ICCOM-CNR UOS Pisa , Research Area, Via Moruzzi 1, I-56124 Pisa, Italy
| | - Stefano Zacchini
- Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna , Viale Risorgimento 4, I-40136 Bologna, Italy
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Travia NE, Scott BL, Kiplinger JL. A Rare Tetranuclear Thorium(IV) μ4-Oxo Cluster and Dinuclear Thorium(IV) Complex Assembled by Carbon-Oxygen Bond Activation of 1,2-Dimethoxyethane (DME). Chemistry 2014; 20:16846-52. [DOI: 10.1002/chem.201404551] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Indexed: 11/10/2022]
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6
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Levason W, Reid G, Trayer J, Zhang W. Synthesis, properties and structures of NbOF3 complexes and comparisons with NbOCl3 analogues. Dalton Trans 2014; 43:3649-59. [DOI: 10.1039/c3dt53322k] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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7
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Favero L, Marchetti F, Pampaloni G, Zacchini S. The interaction of molybdenum pentachloride with O- and S-heterocycles. Dalton Trans 2014; 43:495-504. [DOI: 10.1039/c3dt52271g] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Marchetti F, Pampaloni G, Pinzino C, Zacchini S. Stable [M2F11]-(M = Nb, Ta) Salts of Protonated 1,3-Dimethoxybenzene. Eur J Inorg Chem 2013. [DOI: 10.1002/ejic.201300961] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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9
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Dolci S, Marchetti F, Pampaloni G, Zacchini S. The Reactivity of Molybdenum Pentachloride with Ester Molecules: Ester Activation, Metal Reduction, and Synthesis of 1D Coordination Polymers. Eur J Inorg Chem 2013. [DOI: 10.1002/ejic.201201217] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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10
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Funaioli T, Marchetti F, Pampaloni G, Zacchini S. Ligand-interchange reactions between M(iv) (M = Ti, V) oxide bis-acetylacetonates and halides of high-valent group 4 and 5 metals. A synthetic and electrochemical study. Dalton Trans 2013; 42:14168-77. [DOI: 10.1039/c3dt51378e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Marchetti F, Pampaloni G, Zacchini S. The reactivity of molybdenum pentachloride with ethers: routes to the synthesis of MoIVCl4 adducts, Mo(v) chlorido-alkoxides and Mo(v) oxydo-chlorides. Dalton Trans 2013; 42:15226-34. [DOI: 10.1039/c3dt51797g] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Bortoluzzi M, Marchetti F, Pampaloni G, Pucino M, Zacchini S. Coordination complexes of NbX5 (X = F, Cl) with (N,O)- and (O,O)-donor ligands and the first X-ray characterization of a neutral NbF5 adduct. Dalton Trans 2013; 42:13054-64. [DOI: 10.1039/c3dt50930c] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Marchetti F, Pampaloni G. Interaction of niobium and tantalum pentahalides with O-donors: coordination chemistry and activation reactions. Chem Commun (Camb) 2012; 48:635-53. [DOI: 10.1039/c1cc14592d] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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14
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Marchetti F, Pampaloni G. The reactivity of NbX5 (X=F, Cl) with lactons, lactams, and the synthesis of the first nucleobase-containing niobium complex. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2011.06.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Marchetti F, Pampaloni G, Patil Y, Raspolli Galletti AM, Hayatifar M. Easily accessible oxygen-containing derivatives of niobium pentachloride as catalytic precursors for ethylene polymerization. POLYM INT 2011. [DOI: 10.1002/pi.3139] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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16
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Further insights into the chemistry of niobium and tantalum pentahalides with 1,2-dialkoxyalkanes: Synthesis of bromo- and iodoalkoxides, spectroscopic and computational studies. Polyhedron 2011. [DOI: 10.1016/j.poly.2011.03.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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17
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Room-temperature long-lived [Nb2F11]− salts of radical cations of simple arenes: EPR, UV–Vis and DFT results. J Organomet Chem 2011. [DOI: 10.1016/j.jorganchem.2010.11.042] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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18
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Marchetti F, Pampaloni G. Characterization and thermal activation of adducts of Group 4 tetrahalides with 1,2-dialkoxyalkanes. Inorganica Chim Acta 2010. [DOI: 10.1016/j.ica.2010.05.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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19
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Marchetti F, Pinzino C, Zacchini S, Pampaloni G. Long-Lived Radical Cations of Monocyclic Arenes at Room Temperature Obtained by NbF5 Acting as an Oxidizing Agent and Counterion Precursor. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201001572] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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20
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Marchetti F, Pinzino C, Zacchini S, Pampaloni G. Long-Lived Radical Cations of Monocyclic Arenes at Room Temperature Obtained by NbF5 Acting as an Oxidizing Agent and Counterion Precursor. Angew Chem Int Ed Engl 2010; 49:5268-72. [DOI: 10.1002/anie.201001572] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Marchetti F, Pampaloni G, Zacchini S. Preparation and Reactivity of Mono‐ and Dinuclear Derivatives of Niobium and Tantalum Pentahalides with Alkyl Aryl Ethers. Eur J Inorg Chem 2010. [DOI: 10.1002/ejic.200900896] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Fabio Marchetti
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, 56126 Pisa, Italy, Fax: +39‐050‐221‐246
| | - Guido Pampaloni
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, 56126 Pisa, Italy, Fax: +39‐050‐221‐246
| | - Stefano Zacchini
- Dipartimento di Chimica Fisica e Inorganica, Università di Bologna, Viale Risorgimento 4, 40136 Bologna, Italy
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22
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Dolci S, Marchetti F, Pampaloni G, Zacchini S. A systematic study on the activation of simple polyethers by MoCl5 and WCl6. Dalton Trans 2010; 39:5367-76. [DOI: 10.1039/c001377c] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Marchetti F, Pampaloni G, Zacchini S. 19F NMR spectroscopy as useful tool for determining the structure in solution of coordination compounds of MF5 (M=Nb, Ta). J Fluor Chem 2010. [DOI: 10.1016/j.jfluchem.2009.09.014] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Bini R, Chiappe C, Marchetti F, Pampaloni G, Zacchini S. Structures and Unusual Rearrangements of Coordination Adducts of MX5 (M = Nb, Ta; X = F, Cl) with Simple Diethers. A Crystallographic, Spectroscopic, and Computational Study. Inorg Chem 2009; 49:339-51. [DOI: 10.1021/ic9020806] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Riccardo Bini
- Dipartimento di Chimica, Università di Firenze, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Italy
| | - Cinzia Chiappe
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, I-56126 Pisa, Italy
| | - Fabio Marchetti
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, I-56126 Pisa, Italy
| | - Guido Pampaloni
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, I-56126 Pisa, Italy
| | - Stefano Zacchini
- Dipartimento di Chimica Fisica e Inorganica, Università di Bologna, Viale Risorgimento 4, I-40136 Bologna, Italy
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Epoxide ring opening and insertion into the M–X bond of niobium and tantalum pentahalides: Synthesis of dihalide-tris(2-haloalcoholato) complexes. Polyhedron 2009. [DOI: 10.1016/j.poly.2009.02.037] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Marchetti F, Pampaloni G, Zacchini S. Fragmentation of oxygen-containing molecules via C–O bond cleavage promoted by coordination to niobium and tantalum pentahalides. Dalton Trans 2009:6759-72. [DOI: 10.1039/b905023j] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Marchetti F, Pampaloni G, Zacchini S. The reactivity of 1,1-dialkoxyalkanes with niobium and tantalum pentahalides. Formation of coordination compounds, C–H and C–C bond activation and the X-ray structure of the stable carboxonium species [Me2CCHC(OMe)Me][NbCl5(OMe)]. Dalton Trans 2009:8096-106. [DOI: 10.1039/b907774j] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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28
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Marchetti F, Pampaloni G, Zacchini S. Unusual room temperature activation of 1,2-dialkoxyalkanes by niobium and tantalum pentachlorides. Dalton Trans 2008:7026-35. [PMID: 19050789 DOI: 10.1039/b810210d] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The outcome of the reactions of MCl(5) (M = Nb, 1a; M = Ta, 1b) with 1,2-dialkoxyalkanes [i.e. MeO(CH(2))(2)OMe (dme), EtO(CH(2))(2)OEt, MeOCH(2)CH(Me)OMe, MeO(CH(2))(2)OCH(2)Cl, MeO(CH(2))(2)O(CH(2))(2)OMe (diglyme)] depends strictly on the stoichiometry. In the 1 : 1 molar ratio reactions, single C-O bond cleavage occurs, resulting in formation of alkyl chloride and of the complexes [upper bond 1 start]MCl(4)[O(R)CH(R')CH(2)O][upper bond 1 end] [M = Nb, R = Me, R' = H, 3a; M = Ta, R = Me, R' = H, 3b; M = Nb, R = Et, R' = H, 5; M = Nb, R = R' = Me, 6; M = Nb, R = CH(2)Cl, R' = H, 7; M = Nb, R = (CH(2))(2)O(Me)NbCl(5), R' = H, 8], which have been characterized spectroscopically. Moreover, minor amounts of the oxo-bridged adducts MOCl(3)(dme)MCl(5) (M = Nb, 4a; M = Ta, 4b) have been isolated in the reactions involving dme. On the other hand, compounds react with two (or more) equivalents of dme mainly via a multiple C-O bond cleavage process, affording MOCl(3)(dme) (M = Nb, 2a; M = Ta, 2b), 1,4-dioxane and methyl chloride. The oxychloride compounds MOCl(3) (M = Nb, 11a; M = Ta, 11b) have been efficiently obtained by addition of TiCl(4) to 2. Compound 2a is reduced in high yield to the Nb(III) species NbCl(3)(dme), 12, upon treatment with SnBu(3)H. The oxychloride NbOCl(3)(diglyme), 9, 1,4-dioxane, CH(3)Cl and the hexachloroniobate salt [MeOCH(2)CH(2)OCH(2)CH(2)O(H)Me][NbCl(6)], 10, have been identified as products of the reaction of 1a with two equivalents of diglyme. The 1 : 2 molar ratio reaction of 1a with MeOCH(2)CH(Me)OMe gives 2,5-dimethyl-1,4-dioxane. Compound 1a reacts with two equivalents of EtO(CH(2))(2)OEt or MeO(CH(2))(2)OCH(2)Cl yielding Cl(CH(2))(2)OCH(2)CH(3) or O(CH(2)Cl)(2) and diglyme, respectively, but not dioxane, suggesting that fragmentation pathways different from that found for dme are operating. The X-ray molecular structures of 4a, 4b and 10 have been determined.
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Affiliation(s)
- Fabio Marchetti
- Università di Pisa, Dipartimento di Chimica e Chimica Industriale, Pisa, Italy
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