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Tomsu G, Stöger B, Kirchner K. Synthesis and characterization of pyrrole-based group 4 PNP pincer complexes. MONATSHEFTE FUR CHEMIE 2024; 155:173-181. [PMID: 38440089 PMCID: PMC10908616 DOI: 10.1007/s00706-024-03171-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 01/03/2024] [Indexed: 03/06/2024]
Abstract
The synthesis, characterization, and reactivity of several group 4 metal complexes featuring a central anionic pyrrole moiety connected via CH2 linkers to two phosphine donors is described. Treatment of [P(NH)P-iPr] with [MCl4(THF)2] (M = Zr, Hf) in the presence of base yields the dimeric complexes [M(PNPiPr)(μ-Cl)(Cl)2]2 featuring two bridging chloride ligands. These complexes react with sodium cyclopentadienyl and SiMe3I to give the mononuclear complexes [M(PNPiPr)(η5-Cp)(Cl)2] and [M(PNPiPr)(I)3], respectively. The latter react with MeMgBr to form the trialkyl complexes [M(PNPiPr)(Me)3]. Upon treatment of [Ti(NMe2)4] with [P(NH)P-iPr] a complex with the general formula [Ti(PNPiPr)(NMe2)3] is obtained. DFT calculations revealed that the most stable species is [Ti(κ1N- PNPiPr)(NMe2)3] featuring a κ1N-bound PNP ligand. When [P(NH)P-iPr] is reacted with [Ti(NMe2)4] in CH2Cl2 complex [Ti(PNPiPr)(Cl)2(NMe2)] is formed. Treatment of a solution of [P(NH)P-iPr] and [Zr(NMe2)4] with SiMe3Br affords the anionic seven-coordinate tetrabromo complex [Zr(PNPiPr)(Br)4][H2NMe2]. The corresponding hafnium complex [Hf(PNPiPr)(Br)4][H2NEt2] is obtained in similar fashion by utilizing [Hf(NEt2)4] as metal precursor. All complexes are characterized by means of NMR spectroscopy. Representative complexes were also characterized by X-ray crystallography. Graphical abstract Supplementary Information The online version contains supplementary material available at 10.1007/s00706-024-03171-x.
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Affiliation(s)
- Gerald Tomsu
- Institute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163-AC, 1060 Vienna, Austria
| | - Berthold Stöger
- X-Ray Center, TU Wien, Getreidemarkt 9/163-AC, 1060 Vienna, Austria
| | - Karl Kirchner
- Institute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163-AC, 1060 Vienna, Austria
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2
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Tomsu G, Stöger B, Kirchner K. Pyrrole-Based Ti(III) and Ti(IV) PNP Pincer Complexes: Insertion of Ketones into the Ti(IV)-Phosphorus Bond. Organometallics 2023; 42:2999-3004. [PMID: 37886626 PMCID: PMC10598877 DOI: 10.1021/acs.organomet.3c00327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Indexed: 10/28/2023]
Abstract
The synthesis, characterization, and reactivity of pyrrole-based Ti(III) and Ti(IV) PNP pincer complexes are described. [P(NH)P-iPr] (1) reacts with [TiCl4(THF)2] at room temperature in the presence of NEt3 to afford the Ti(IV) complex [Ti(PNPiPr)(Cl)3]. This complex reacts with acetone and cyclopentanone to give complexes [Ti(PNOacet-iPr)(Cl)3] and [Ti(PNOcyclo-iPr)(Cl)3], respectively. Insertion of the ketone into the Ti(IV)-P bond took place, forming a new tridendate PNO-ligand. Treatment of [TiCl3(THF)3] with the lithium salt of [P(NH)P-iPr] afforded, upon workup, complex [Ti(PNP-iPr)(Cl)2(THF)], a paramagnetic complex with an μeff value of 1.8(1) μB which corresponds to one unpaired electron and a formal oxidation state of +III. This compound does not react with ketones. A mechanistic proposal based on DFT calculations is presented. Ketone insertion proceeds via an associative reaction initiated by ketone coordination at the metal center, followed by the opening of the five-membered chelate ring, and finally an intramolecular nucleophilic attack of the noncoordinated phosphine arm at the carbonyl atom of the ketone. All complexes were characterized by X-ray crystallography.
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Affiliation(s)
- Gerald Tomsu
- Institute
of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163-AC, A-1060 Wien, Austria
| | - Berthold Stöger
- X-ray
Center, TU Wien, Getreidemarkt
9/163, A-1060 Wien, Austria
| | - Karl Kirchner
- Institute
of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163-AC, A-1060 Wien, Austria
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3
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Collett JD, Krause JA, Guan H. Nickel Hydride Complexes Supported by a Pyrrole-Derived Phosphine Ligand. Organometallics 2022. [DOI: 10.1021/acs.organomet.1c00694] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joel D. Collett
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati, Ohio 45221-0172, United States
| | - Jeanette A. Krause
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati, Ohio 45221-0172, United States
| | - Hairong Guan
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati, Ohio 45221-0172, United States
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4
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Bhat SA, Sonawane SC, Mague JT, Balakrishna MS. Synthesis and characterization of Mo(0) and W(0) complexes of bis(azol-1-yl)methane based bisphosphines. J COORD CHEM 2021. [DOI: 10.1080/00958972.2021.1955251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Sajad A. Bhat
- Department of Chemistry, Phosphorus Laboratory, Indian Institute of Technology Bombay, Powai, Mumbai, India
| | - Sachin C. Sonawane
- Department of Chemistry, Phosphorus Laboratory, Indian Institute of Technology Bombay, Powai, Mumbai, India
| | - Joel T. Mague
- Department of Chemistry, Tulane University, New Orleans, LA, USA
| | - Maravanji S. Balakrishna
- Department of Chemistry, Phosphorus Laboratory, Indian Institute of Technology Bombay, Powai, Mumbai, India
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5
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Jha VK, Das S, Subramaniyan V, Guchhait T, Dakua KK, Mishra S, Mani G. Synthesis, structural characterization, and bonding analysis of two-coordinate copper(I) and silver(I) complexes of pyrrole-based bis(phosphinimine): new metal-pyrrole ring π-interactions. Dalton Trans 2021; 50:8036-8044. [PMID: 34013307 DOI: 10.1039/d1dt01091c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The reaction between 2,5-bis(diphenylphosphinomethyl)pyrrole and Me3SiN3 gave the new pyrrole-based bis(phosphinimine) L1H in an excellent yield. L1H reacts with [CuCl(COD)]2, AgBF4, or AgOTf to give the corresponding two-coordinate mononuclear ionic complex formulated as [M{(L1H)-κ2N,N}]+[X]- where M = Cu and Ag; X = [CuCl2], BF4 or OTf. Their single crystal X-ray diffraction studies confirmed the two-coordinate geometry formed by the chelate bonding mode of L1H. These 10-membered metalacycles exhibit planar chirality and were also characterized by spectroscopic methods. In addition, in all three structures, there exists a hitherto unknown π-interaction between the pyrrole ring atoms and metal, represented as η2-(Cα-N) in the copper(i) complex, and η3-(Cα-N-Cα') in the silver(i) complexes. These weak interactions were supported by DFT calculations in terms of their electron densities, non-covalent interaction plots and the decrease in the aromaticity of the pyrrole ring.
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Affiliation(s)
- Vikesh Kumar Jha
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur-721 302, India.
| | - Sanghamitra Das
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur-721 302, India.
| | - Vasudevan Subramaniyan
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur-721 302, India.
| | - Tapas Guchhait
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur-721 302, India.
| | - Kishan Kumar Dakua
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur-721 302, India.
| | - Sabyashachi Mishra
- Department of Chemistry and Centre for Computational and Data Sciences, Indian Institute of Technology Kharagpur, Kharagpur-721 302, India.
| | - Ganesan Mani
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur-721 302, India.
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6
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Idelson C, Webster L, Krämer T, Chadwick FM. Asymmetric bis-PNP pincer complexes of zirconium and hafnium - a measure of hemilability. Dalton Trans 2020; 49:16653-16656. [PMID: 33191415 DOI: 10.1039/d0dt03544k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Asymmetrically-bound pyrrolide-based bis-PNP pincer complexes of zirconium and hafnium have been formed. The [κ2-PNPPh][κ3-PNPPh]MCl2 species are in direct contrast to previous zirconium PNP pincer complexes. The pincer ligands are fluxional in their binding and the energy barrier for exchange has been approximated using VT-NMR spectroscopy and the result validated by DFT calculations.
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Affiliation(s)
- Celia Idelson
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City, Shepherds Bush, London, W12 0BZ, UK.
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7
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Kawakami R, Kuriyama S, Tanaka H, Konomi A, Yoshizawa K, Nishibayashi Y. Iridium-catalyzed Formation of Silylamine from Dinitrogen under Ambient Reaction Conditions. CHEM LETT 2020. [DOI: 10.1246/cl.200254] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Ryosuke Kawakami
- Department of Systems Innovation, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Shogo Kuriyama
- Department of Systems Innovation, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hiromasa Tanaka
- School of Liberal Arts and Science, Daido University, Minami-ku, Nagoya, Aichi 457-8530, Japan
| | - Asuka Konomi
- Institute for Materials Chemistry and Engineering, Kyushu University, Nishi-ku, Fukuoka 819-0395, Japan
| | - Kazunari Yoshizawa
- Institute for Materials Chemistry and Engineering, Kyushu University, Nishi-ku, Fukuoka 819-0395, Japan
| | - Yoshiaki Nishibayashi
- Department of Systems Innovation, School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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8
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Merz LS, Ballmann J, Gade LH. Phosphines and
N
‐Heterocycles Joining Forces: an Emerging Structural Motif in PNP‐Pincer Chemistry. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000206] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Lukas S. Merz
- Anorganisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Joachim Ballmann
- Anorganisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Lutz H. Gade
- Anorganisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
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9
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Thompson CV, Tonzetich ZJ. Pincer ligands incorporating pyrrolyl units: Versatile platforms for organometallic chemistry and catalysis. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2020. [DOI: 10.1016/bs.adomc.2020.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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10
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Tanabe Y, Sekiguchi Y, Tanaka H, Konomi A, Yoshizawa K, Kuriyama S, Nishibayashi Y. Preparation and reactivity of molybdenum complexes bearing pyrrole-based PNP-type pincer ligand. Chem Commun (Camb) 2020; 56:6933-6936. [DOI: 10.1039/d0cc02852e] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Molybdenum complexes bearing an anionic pyrrole-based PNP-type pincer ligand have been prepared and have been found to work as catalysts for the conversion of N2 into NH3 under ambient conditions.
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Affiliation(s)
- Yoshiaki Tanabe
- Department of Systems Innovation
- School of Engineering
- The University of Tokyo
- Hongo
- Bunkyo-ku
| | - Yoshiya Sekiguchi
- Department of Systems Innovation
- School of Engineering
- The University of Tokyo
- Hongo
- Bunkyo-ku
| | - Hiromasa Tanaka
- Institute for Materials Chemistry and Engineering
- Kyushu University
- Nishi-ku
- Fukuoka 819-0395
- Japan
| | - Asuka Konomi
- Institute for Materials Chemistry and Engineering
- Kyushu University
- Nishi-ku
- Fukuoka 819-0395
- Japan
| | - Kazunari Yoshizawa
- Institute for Materials Chemistry and Engineering
- Kyushu University
- Nishi-ku
- Fukuoka 819-0395
- Japan
| | - Shogo Kuriyama
- Department of Systems Innovation
- School of Engineering
- The University of Tokyo
- Hongo
- Bunkyo-ku
| | - Yoshiaki Nishibayashi
- Department of Systems Innovation
- School of Engineering
- The University of Tokyo
- Hongo
- Bunkyo-ku
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11
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Kato T, Kuriyama S, Nakajima K, Nishibayashi Y. Catalytic C-H Borylation Using Iron Complexes Bearing 4,5,6,7-Tetrahydroisoindol-2-ide-Based PNP-Type Pincer Ligand. Chem Asian J 2019; 14:2097-2101. [PMID: 30980480 DOI: 10.1002/asia.201900501] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Indexed: 01/23/2023]
Abstract
Catalytic C-H borylation has been reported using newly designed iron complexes bearing a 4,5,6,7-tetrahydroisoindol-2-ide-based PNP pincer ligand. The reaction tolerated various five-membered heteroarenes, such as pyrrole derivatives, as well as six-membered aromatic compounds, such as toluene. Successful examples of the iron-catalyzed sp3 C-H borylation of anisole derivatives were also presented.
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Affiliation(s)
- Takeru Kato
- Department of Systems Innovation, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Shogo Kuriyama
- Department of Systems Innovation, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Kazunari Nakajima
- Frontier Research Center for Energy and Resources, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Yoshiaki Nishibayashi
- Department of Systems Innovation, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8656, Japan
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12
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Agapova A, Alberico E, Kammer A, Junge H, Beller M. Catalytic Dehydrogenation of Formic Acid with Ruthenium‐PNP‐Pincer Complexes: Comparing N‐Methylated and NH‐Ligands. ChemCatChem 2019. [DOI: 10.1002/cctc.201801897] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Anastasiya Agapova
- Leibniz-Institut für Katalyse e. V. an derUniversität Rostock Albert-Einstein-Straße 29a 18059 Rostock Germany
| | - Elisabetta Alberico
- Leibniz-Institut für Katalyse e. V. an derUniversität Rostock Albert-Einstein-Straße 29a 18059 Rostock Germany
- Istituto di Chimica BiomolecolareConsiglio Nazionale delle Ricerche tr. La Crucca 3 07100 Sassari Italy
| | - Anja Kammer
- Leibniz-Institut für Katalyse e. V. an derUniversität Rostock Albert-Einstein-Straße 29a 18059 Rostock Germany
| | - Henrik Junge
- Leibniz-Institut für Katalyse e. V. an derUniversität Rostock Albert-Einstein-Straße 29a 18059 Rostock Germany
| | - Matthias Beller
- Leibniz-Institut für Katalyse e. V. an derUniversität Rostock Albert-Einstein-Straße 29a 18059 Rostock Germany
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13
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Das S, Subramaniyan V, Mani G. Nickel(II) and Palladium(II) Complexes Bearing an Unsymmetrical Pyrrole-Based PNN Pincer and Their Norbornene Polymerization Behaviors versus the Symmetrical NNN and PNP Pincers. Inorg Chem 2019; 58:3444-3456. [PMID: 30767515 DOI: 10.1021/acs.inorgchem.8b03562] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Unsymmetrical pincers have been shown to be better than the corresponding symmetrical pincers in several catalysis reactions. A new unsymmetrical PNN propincer, 2-(3,5-dimethylpyrazolylmethyl)-5-(diphenylphosphinomethyl)pyrrole (1), was synthesized from pyrrole through Mannich bases in a good yield. In addition, the new byproduct 2-(3,5-dimethylpyrazolylmethyl)-5-(dimethylaminomethyl)- N-(hydroxymethyl)pyrrole was also isolated. The reaction of 1 with [PdCl2(PhCN)2] and Et3N in toluene yielded [PdCl{C4H2N-2-(CH2Me2pz)-5-(CH2PPh2)-κ3 P,N,N}] (2). The analogous reaction between 1 and [NiCl2(DME)] or NiX2 (X = Br, I) in the presence of NEt3 in acetonitrile afforded [NiX{C4H2N-2-(CH2Me2pz)-5-(CH2PPh2)-κ3 P,N,N}] (3; X = Cl, Br, I). All complexes were structurally characterized. The norbornene polymerization behaviors of the unsymmetrical pincer complexes 2 and 3 in the presence of MMAO or EtAlCl2 were compared with those of the symmetrical pincer complexes chloro[2,5-bis(3,5-dimethylpyrazolylmethyl)pyrrolido]palladium(II) (NNN), chloro[2,5-bis(diphenylphosphinomethyl)pyrrolido]palladium(II), and chloro[2,5-bis(diphenylphosphinomethyl)pyrrolido]nickel(II) (PNP) at different temperatures. The PNN and NNN complexes exhibited far greater activity on the order of 107 g of PNB/mol/h, with quantitative yields in some cases, in comparison to the PNP pincer palladium and nickel complexes. This trend was also supported by the iPr group substituted PNP nickel and palladium pincer complexes. These polymerization behaviors are explained using steric crowding around the metal atom with the support of NMR studies and suggested that the activity increases as the Npyrazole donor increases. Polymers were characterized by 1H NMR, IR, TGA, and powder XRD methods.
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Affiliation(s)
- Sanghamitra Das
- Department of Chemistry , Indian Institute of Technology Kharagpur , Kharagpur , West Bengal , India 721 302
| | - Vasudevan Subramaniyan
- Department of Chemistry , Indian Institute of Technology Kharagpur , Kharagpur , West Bengal , India 721 302
| | - Ganesan Mani
- Department of Chemistry , Indian Institute of Technology Kharagpur , Kharagpur , West Bengal , India 721 302
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14
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Kumar S, Jana O, Subramaniyan V, Mani G. The ‘reverse transmetalation’ reaction of the pyrrole-based PNP pincer Ni(II) complexes: X-ray structures of binuclear silver(I) and thiocyanate nickel(II) complexes. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2018.05.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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15
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Krishnan VM, Davis I, Baker TM, Curran DJ, Arman HD, Neidig ML, Liu A, Tonzetich ZJ. Backbone Dehydrogenation in Pyrrole-Based Pincer Ligands. Inorg Chem 2018; 57:9544-9553. [PMID: 30040391 DOI: 10.1021/acs.inorgchem.8b01643] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Treatment of both [CoCl( tBuPNP)] and [NiCl( tBuPNP)] ( tBuPNP = anion of 2,5-bis((di- tert-butylphosphino)methyl)pyrrole) with one equivalent of benzoquinone affords the corresponding chloride complexes containing a dehydrogenated PNP ligand, tBudPNP ( tBudPNP = anion of 2,5-bis((di- tert-butylphosphino)methylene)-2,5-dihydropyrrole). Dehydrogenation of PNP to dPNP results in minimal change to steric profile of the ligand but has important consequences for the resulting redox potentials of the metal complexes, resulting in the ability to isolate both [CoH( tBudPNP)] and [CoEt( tBudPNP)], which are more challenging (hydride) or not possible (ethyl) to prepare with the parent PNP ligand. Electrochemical measurements with both the Co and Ni dPNP species demonstrate a substantial shift in redox potentials for both the M(II/III) and M(II/I) couples. In the case of the former, oxidation to trivalent Co was found to be reversible, and subsequent reaction with AgSbF6 afforded a rare example of a square-planar Co(III) species. Corresponding reduction of [CoCl( tBudPNP)] with KC8 produced the diamagnetic Co(I) species, [Co(N2)( tBudPNP)]. Further reduction of the Co(I) complex was found to generate a pincer-based π-radical anion that demonstrated well-resolved EPR features to the four hydrogen atoms and lone nitrogen atom of the ligand with minor contributions from cobalt and coordinated N2. Changes in the electronic character of the PNP ligand upon dehydrogenation are proposed to result from loss of aromaticity in the pyrrole ligand, resulting in a more reducing central amido donor. DFT calculations on the Co(II) complexes were performed to shed further insight into the electronic structure of the pincer complexes.
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Affiliation(s)
- V Mahesh Krishnan
- Department of Chemistry , University of Texas at San Antonio (UTSA) , San Antonio , Texas 78249 , United States
| | - Ian Davis
- Department of Chemistry , University of Texas at San Antonio (UTSA) , San Antonio , Texas 78249 , United States
| | - Tessa M Baker
- Department of Chemistry , University of Rochester , Rochester , New York 14627 , United States
| | - Daniel J Curran
- Department of Chemistry , University of Rochester , Rochester , New York 14627 , United States
| | - Hadi D Arman
- Department of Chemistry , University of Texas at San Antonio (UTSA) , San Antonio , Texas 78249 , United States
| | - Michael L Neidig
- Department of Chemistry , University of Rochester , Rochester , New York 14627 , United States
| | - Aimin Liu
- Department of Chemistry , University of Texas at San Antonio (UTSA) , San Antonio , Texas 78249 , United States
| | - Zachary J Tonzetich
- Department of Chemistry , University of Texas at San Antonio (UTSA) , San Antonio , Texas 78249 , United States
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16
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Nakayama S, Morisako S, Yamashita M. Synthesis and Application of Pyrrole-Based PNP–Ir Complexes to Catalytic Transfer Dehydrogenation of Cyclooctane. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00072] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Shin Nakayama
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27, Kasuga, Bunkyo-ku, 112-8551 Tokyo, Japan
| | - Shogo Morisako
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Makoto Yamashita
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
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17
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18
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Kessler JA, Iluc VM. NI(ii) phosphine and phosphide complexes supported by a PNP-pyrrole pincer ligand. Dalton Trans 2017; 46:12125-12131. [PMID: 28869266 DOI: 10.1039/c7dt02784b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction between [(PNpyrP)NiCl] (1, PNpyrP = 2,5-bis((di-iso-propylphosphino)-methyl)-1H-pyrrolide) and TlPF6 in the presence of a monodentate phosphine ligand led to cationic nickel phosphine and phosphite complexes, [(PNpyrP)Ni(PHPh2)][PF6] (2), [(PNpyrP)Ni(PMe3)][PF6] (3), and [(PNpyrP)Ni{P(OMe)3}][PF6] (4). Compound 2 can be deprotonated resulting in the generation of a terminal phosphido complex, [(PNpyrP)Ni(PPh2)] (5). When 3 is subjected to a base, a methyl proton of PMe3 is abstracted to afford [(PNpyrP)Ni(CH2PMe2)] (6), containing a methylene bridge between Ni and the external phosphine. Compounds 2-6 were characterized by single crystal X-ray diffraction in addition to multi-nuclear NMR spectroscopy and elemental analysis.
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Affiliation(s)
- Julie A Kessler
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
| | - Vlad M Iluc
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
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19
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Nakajima K, Kato T, Nishibayashi Y. Hydroboration of Alkynes Catalyzed by Pyrrolide-Based PNP Pincer–Iron Complexes. Org Lett 2017; 19:4323-4326. [DOI: 10.1021/acs.orglett.7b01995] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Kazunari Nakajima
- Department of Systems Innovation,
School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takeru Kato
- Department of Systems Innovation,
School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yoshiaki Nishibayashi
- Department of Systems Innovation,
School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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20
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Ehrlich N, Kreye M, Baabe D, Schweyen P, Freytag M, Jones PG, Walter MD. Synthesis and Electronic Ground-State Properties of Pyrrolyl-Based Iron Pincer Complexes: Revisited. Inorg Chem 2017; 56:8415-8422. [DOI: 10.1021/acs.inorgchem.7b01078] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nico Ehrlich
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Markus Kreye
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Dirk Baabe
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Peter Schweyen
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Matthias Freytag
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Peter G. Jones
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Marc D. Walter
- Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
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21
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Holland AM, Oliver AG, Iluc VM. Iron pyrrole-based PNP pincer ligand complexes as catalyst precursors. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2017; 73:569-574. [DOI: 10.1107/s2053229617009287] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 06/20/2017] [Indexed: 11/10/2022]
Abstract
The structure of a pincer ligand consists of a backbone and two `arms' which typically contain a P or N atom. They are tridentate ligands that coordinate to a metal center in a meridional configuration. A series of three iron complexes containing the pyrrole-based PNP pincer ligand 2,5-bis[(diisopropylphosphanyl)methyl]pyrrolide (PNpyrP) has been synthesized. These complexes are possible precursors to new iron catalysts. {2,5-Bis[(diisopropylphosphanyl)methyl]pyrrolido-κ3
P,N,P′}carbonylchlorido(trimethylphosphane-κP)iron(II), [Fe(C18H34NP2)Cl(C3H9P)(CO)] or [Fe(PNpyrP)Cl(PMe3)(CO)], (I), has a slightly distorted octahedral geometry, with the Cl and CO ligands occupying the apical positions. {2,5-Bis[(diisopropylphosphanyl)methyl]pyrrolido-κ3
P,N,P′}chlorido(pyridine-κN)iron(II), [Fe(C18H34NP2)Cl(C5H5N)] or [Fe(PNpyrP)Cl(py)] (py is pyridine), (II), is a five-coordinate square-pyramidal complex, with the pyridine ligand in the apical position. {2,5-Bis[(diisopropylphosphanyl)methyl]pyrrolido-κ3
P,N,P′}dicarbonylchloridoiron(II), [Fe(C18H34NP2)Cl(CO)2] or [Fe(PNpyrP)Cl(CO)2], (III), is structurally similar to (I), but with the PMe3 ligand replaced by a second carbonyl ligand from the reaction of (II) with CO. The two carbonyl ligands are in a cis configuration, and there is positional disorder of the chloride and trans carbonyl ligands.
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22
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Thompson CV, Arman HD, Tonzetich ZJ. A Pyrrole-Based Pincer Ligand Permits Access to Three Oxidation States of Iron in Organometallic Complexes. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00144] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- C. Vance Thompson
- Department of Chemistry, University of Texas at San Antonio (UTSA), San Antonio, Texas 78249, United States
| | - Hadi D. Arman
- Department of Chemistry, University of Texas at San Antonio (UTSA), San Antonio, Texas 78249, United States
| | - Zachary J. Tonzetich
- Department of Chemistry, University of Texas at San Antonio (UTSA), San Antonio, Texas 78249, United States
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23
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Jana A, Bhowmick S, Kaur S, Kashyap HK, Das N. Design of a flexible organometallic tecton: host–guest chemistry with picric acid and self-assembly of platinum macrocycles. Dalton Trans 2017; 46:1986-1995. [DOI: 10.1039/c6dt03498e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new “flexible” and ditopic Pt(ii) organometallic compound is a tecton for the self-assembly of neutral metallacycles. It also exhibits significant binding affinity for picric acid.
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Affiliation(s)
- Achintya Jana
- Department of Chemistry
- Indian Institute of Technology Patna
- Patna 801103
- India
| | - Sourav Bhowmick
- Department of Chemistry
- Indian Institute of Technology Patna
- Patna 801103
- India
| | - Supreet Kaur
- Department of Chemistry
- Indian Institute of Technology Delhi
- Hauz Khas, New Delhi 110016
- India
| | - Hemant K. Kashyap
- Department of Chemistry
- Indian Institute of Technology Delhi
- Hauz Khas, New Delhi 110016
- India
| | - Neeladri Das
- Department of Chemistry
- Indian Institute of Technology Patna
- Patna 801103
- India
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24
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Small molecule binding and activation on a cationic ruthenium center of a pincer complex. J Organomet Chem 2016. [DOI: 10.1016/j.jorganchem.2016.10.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Affiliation(s)
- Sean P. Vilanova
- Department
of Chemistry and
Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Vlad M. Iluc
- Department
of Chemistry and
Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
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26
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Kreye M, Freytag M, Jones PG, Williard PG, Bernskoetter WH, Walter MD. Homolytic H2 cleavage by a mercury-bridged Ni(i) pincer complex [{(PNP)Ni}2{μ-Hg}]. Chem Commun (Camb) 2015; 51:2946-9. [DOI: 10.1039/c4cc09743b] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The Hg-bridged (PNP)Ni-complex acts as a synthon for Ni(i) and homolytically cleaves H2 to yield [(PNP)NiH].
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Affiliation(s)
- Markus Kreye
- Institut für Anorganische und Analytische Chemie
- Technische Universität
- 38106 Braunschweig
- Germany
| | - Matthias Freytag
- Institut für Anorganische und Analytische Chemie
- Technische Universität
- 38106 Braunschweig
- Germany
| | - Peter G. Jones
- Institut für Anorganische und Analytische Chemie
- Technische Universität
- 38106 Braunschweig
- Germany
| | | | | | - Marc D. Walter
- Institut für Anorganische und Analytische Chemie
- Technische Universität
- 38106 Braunschweig
- Germany
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