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Schratzberger H, Stöger B, Veiros LF, Kirchner K. Selective Transfer Semihydrogenation of Alkynes Catalyzed by an Iron PCP Pincer Alkyl Complex. ACS Catal 2023; 13:14012-14022. [PMID: 37942266 PMCID: PMC10629171 DOI: 10.1021/acscatal.3c04156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 09/28/2023] [Indexed: 11/10/2023]
Abstract
Two bench-stable Fe(II) alkyl complexes [Fe(κ3PCP-PCP-iPr)(CO)2(R)] (R = CH2CH2CH3, CH3) were obtained by the treatment of [Fe(κ3PCP-PCP-iPr)(CO)2(H)] with NaNH2 and subsequent addition of CH3CH2CH2Br and CH3I, respectively. The reaction proceeds via the anionic Fe(0) intermediate Na[Fe(κ3PCP-PCP-iPr)(CO)2]. The catalytic performance of both alkyl complexes was investigated for the transfer hydrogenation of terminal and internal alkynes utilizing PhSiH3 and iPrOH as a hydrogen source. Precatalyst activation is initiated by migration of the alkyl ligand to the carbonyl C atom of an adjacent CO ligand. In agreement with previous findings, the rate of alkyl migration follows the order nPr > Me. Accordingly, [Fe(κ3PCP-PCP-iPr)(CO)2(CH2CH2CH3)] is the more active catalyst. The reaction takes place at 25 °C with a catalyst loading of 0.5 mol%. There was no overhydrogenation, and in the case of internal alkynes, exclusively, Z-alkenes are formed. The implemented protocol tolerates a variety of electron-donating and electron-withdrawing functional groups including halides, nitriles, unprotected amines, and heterocycles. Mechanistic investigations including deuterium labeling studies and DFT calculations were undertaken to provide a reasonable reaction mechanism.
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Affiliation(s)
- Heiko Schratzberger
- 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
| | - Luis F. Veiros
- Centro
de
Química Estrutural, Institute of Molecular Sciences, Departamento
de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049 001 Lisboa, Portugal
| | - Karl Kirchner
- Institute
of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163-AC, A-1060 Wien, Austria
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2
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Glatz M, Gorgas N, Stöger B, Pittenauer E, Ferreira L, Veiros LF, Calhorda MJ, Kirchner K. Structural and Electronic Properties of Iron(0) PNP Pincer Complexes. Z Anorg Allg Chem 2021; 647:1429-1435. [PMID: 34413550 PMCID: PMC8360027 DOI: 10.1002/zaac.202100015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 02/16/2021] [Indexed: 11/06/2022]
Abstract
In the present work we have prepared and fully characterized several Fe(0) complexes of the type [Fe(PNP)(CO)2] treating Fe(II) complexes [Fe(PNP)(Cl)2] with KC8 in the presence of carbon monoxide. While complexes [Fe(PNPNMe-iPr)(CO)2], [Fe(PNPNEt-iPr)(CO)2] adopt a trigonal bipyramidal geometry, the bulkier and more electron rich [Fe(PNPNH-tBu)(CO)2] is closer to a square pyramidal geometry. Mössbauer spectra showed isomer shifts very close to 0 and similar to those reported for Fe(I) systems. Quadrupole splitting values range between 2.2 and 2.7 mm s-1 both in experiments and DFT calculations, while those of Fe(I) complexes are much smaller (∼0.6 mm s-1).
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Affiliation(s)
- Mathias Glatz
- Institute of Applied Synthetic Chemistry Vienna University of Technology Getreidemarkt 9/163-AC 1060 Vienna Austria
| | - Nikolaus Gorgas
- Institute of Applied Synthetic Chemistry Vienna University of Technology Getreidemarkt 9/163-AC 1060 Vienna Austria
| | - Berthold Stöger
- X-ray Center Vienna University of Technology Getreidemarkt 9/163-OC 1060 Vienna Austria
| | - Ernst Pittenauer
- Institute of Chemical Technologies and Analytics Vienna University of Technology Getreidemarkt 9 A-1060 Vienna Austria
| | - Liliana Ferreira
- Department of Physics University of Coimbra 3004-516 Coimbra Portugal
- BioISI-Biosystems and Integrative Sciences Institute Faculdade de Ciências Universidade de Lisboa 1749-016 Lisboa Portugal
| | - Luis F Veiros
- Centro de Química Estrutural and Departamento de Engenharia Química Instituto Superior Técnico Universidade de Lisboa Av Rovisco Pais 1049-001 Lisboa Portugal
| | - Maria José Calhorda
- BioISI-Biosystems and Integrative Sciences Institute Faculdade de Ciências Universidade de Lisboa 1749-016 Lisboa Portugal
| | - Karl Kirchner
- Institute of Applied Synthetic Chemistry Vienna University of Technology Getreidemarkt 9/163-AC 1060 Vienna Austria
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3
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Lapointe S, Khaskin E, Fayzullin RR, Khusnutdinova JR. Nickel(II) Complexes with Electron-Rich, Sterically Hindered PNP Pincer Ligands Enable Uncommon Modes of Ligand Dearomatization. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00558] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Sébastien Lapointe
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Eugene Khaskin
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Robert R. Fayzullin
- Arbuzov Institute of Organic and Physical Chemistry, FCR Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, Kazan 420088, Russian Federation
| | - Julia R. Khusnutdinova
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
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4
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Lapointe S, Khaskin E, Fayzullin RR, Khusnutdinova JR. Stable Nickel(I) Complexes with Electron-Rich, Sterically-Hindered, Innocent PNP Pincer Ligands. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00026] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Sébastien Lapointe
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Eugene Khaskin
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
| | - Robert R. Fayzullin
- Arbuzov Institute of Organic and Physical Chemistry, FCR Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, Kazan 420088, Russian Federation
| | - Julia R. Khusnutdinova
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
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5
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Alig L, Fritz M, Schneider S. First-Row Transition Metal (De)Hydrogenation Catalysis Based On Functional Pincer Ligands. Chem Rev 2018; 119:2681-2751. [PMID: 30596420 DOI: 10.1021/acs.chemrev.8b00555] [Citation(s) in RCA: 497] [Impact Index Per Article: 82.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The use of 3d metals in de/hydrogenation catalysis has emerged as a competitive field with respect to "traditional" precious metal catalyzed transformations. The introduction of functional pincer ligands that can store protons and/or electrons as expressed by metal-ligand cooperativity and ligand redox-activity strongly stimulated this development as a conceptual starting point for rational catalyst design. This review aims at providing a comprehensive picture of the utilization of functional pincer ligands in first-row transition metal hydrogenation and dehydrogenation catalysis and related synthetic concepts relying on these such as the hydrogen borrowing methodology. Particular emphasis is put on the implementation and relevance of cooperating and redox-active pincer ligands within the mechanistic scenarios.
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Affiliation(s)
- Lukas Alig
- Universität Göttingen , Institut für Anorganische Chemie , Tammannstrasse 4 , D-37077 Göttingen , Germany
| | - Maximilian Fritz
- Universität Göttingen , Institut für Anorganische Chemie , Tammannstrasse 4 , D-37077 Göttingen , Germany
| | - Sven Schneider
- Universität Göttingen , Institut für Anorganische Chemie , Tammannstrasse 4 , D-37077 Göttingen , Germany
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6
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Polezhaev AV, Liss CJ, Telser J, Chen C, Caulton KG. A PNNH Pincer Ligand Allows Access to Monovalent Iron. Chemistry 2017; 24:1330-1341. [DOI: 10.1002/chem.201703795] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Indexed: 12/21/2022]
Affiliation(s)
| | - Cameron J. Liss
- Department of Biological, Chemical, and Physical Sciences Roosevelt University 430 S. Michigan Ave Chicago Illinois 60605 USA
| | - Joshua Telser
- Department of Biological, Chemical, and Physical Sciences Roosevelt University 430 S. Michigan Ave Chicago Illinois 60605 USA
| | - Chun‐Hsing Chen
- Department of Chemistry Indiana University Bloomington 47405 Bloomington IN USA
| | - Kenneth G. Caulton
- Department of Chemistry Indiana University Bloomington 47405 Bloomington IN USA
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Obligacion JV, Zhong H, Chirik PJ. Insights into Activation of Cobalt Pre-Catalysts for C( sp2)-H Functionalization. Isr J Chem 2017; 57:1032-1036. [PMID: 29456261 PMCID: PMC5813819 DOI: 10.1002/ijch.201700072] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The activation of readily prepared, air-stable cobalt (II) bis(carboxylate) pre-catalysts for the functionalization of C(sp2)-H bonds has been systematically studied. With the pyridine bis(phosphine) chelate, iPrPNP, treatment of 1-(O2CtBu)2 with either B2Pin2 or HBPin generated cobalt boryl products. With the former, reduction to (iPrPNP)CoIBPin was observed while with the latter, oxidation to the cobalt(III) dihydride boryl, trans-(iPrPNP)Co(H)2BPin occurred. The catalytically inactive cobalt complex, Co[PinB(O2CtBu)2]2, accompanied formation of the cobalt-boryl products in both cases. These results demonstrate that the pre-catalyst activation from cobalt(II) bis(carboxylates), although effective and utilizes an air-stable precursor, is less efficient than activation of cobalt(I) alkyl or cobalt(III) dihydride boryl complexes, which are quantitatively converted to the catalytically relevant cobalt(I) boryl. Related cobalt(III) dihydride silyl and cobalt(I) silyl complexes were also synthesized from treatment of trans-(iPrPNP)Co(H)2BPin and (iPrPNP)CoPh with HSi(OEt)3, respectively. No catalytic silylation of arenes was observed with either complex likely due to the kinetic preference for reversible C-H reductive elimination rather than product- forming C-Si bond formation from cobalt(III). Syntheses of the cobalt(II) bis(carboxylate) and cobalt(I) alkyl of iPrPONOP, a pincer where the methylene spacers have been replaced by oxygen atoms, were unsuccessful due to deleterious P-O bond cleavage of the pincer. Despite their structural similarity, the rich catalytic chemistry of iPrPNP was not translated to iPrPONOP due to the inability to access stable cobalt precursors as a result of ligand decomposition via P-O bond cleavage.
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Affiliation(s)
| | - Hongyu Zhong
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
| | - Paul J Chirik
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
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8
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Anderson NH, Boncella JM, Tondreau AM. Reactivity of Silanes with (
t
Bu
PONOP)Ruthenium Dichloride: Facile Synthesis of Chloro-Silyl Ruthenium Compounds and Formic Acid Decomposition. Chemistry 2017; 23:13617-13622. [DOI: 10.1002/chem.201703722] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Nickolas H. Anderson
- Los Alamos National Laboratory; MPA Division; MS J514 Los Alamos New Mexico 87545 United States
| | - James M. Boncella
- Los Alamos National Laboratory; MPA Division; MS J514 Los Alamos New Mexico 87545 United States
| | - Aaron M. Tondreau
- Los Alamos National Laboratory; MPA Division; MS J514 Los Alamos New Mexico 87545 United States
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9
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Dehydrogenative coupling of alcohols to esters on a silica polyamine composite by immobilized PNN and PONOP pincer complexes of ruthenium. J Organomet Chem 2017. [DOI: 10.1016/j.jorganchem.2017.05.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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10
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Synthesis, characterization and reactivity of vanadium, chromium, and manganese PNP pincer complexes. Inorganica Chim Acta 2017. [DOI: 10.1016/j.ica.2016.02.064] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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11
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Tondreau AM, Boncella JM. The synthesis of PNP-supported low-spin nitro manganese(I) carbonyl complexes. Polyhedron 2016. [DOI: 10.1016/j.poly.2016.04.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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13
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Tondreau AM, Boncella JM. 1,2-Addition of Formic or Oxalic Acid to –N{CH2CH2(PiPr2)}2-Supported Mn(I) Dicarbonyl Complexes and the Manganese-Mediated Decomposition of Formic Acid. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00274] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Aaron M. Tondreau
- Chemistry Division, Los Alamos National Laboratory, MS J514, Los Alamos, New Mexico 87545, United States
| | - James M. Boncella
- Chemistry Division, Los Alamos National Laboratory, MS J514, Los Alamos, New Mexico 87545, United States
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14
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Bauer G, Hu X. Recent developments of iron pincer complexes for catalytic applications. Inorg Chem Front 2016. [DOI: 10.1039/c5qi00262a] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Iron pincer complexes exhibit excellent activity in homogeneous catalysis.
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Affiliation(s)
- Gerald Bauer
- Laboratory of Inorganic Synthesis and Catalysis
- Institute of Chemical Sciences and Engineering
- École Polytechnique Fédérale de Lausanne (EPFL)
- 1015 Lausanne
- Switzerland
| | - Xile Hu
- Laboratory of Inorganic Synthesis and Catalysis
- Institute of Chemical Sciences and Engineering
- École Polytechnique Fédérale de Lausanne (EPFL)
- 1015 Lausanne
- Switzerland
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15
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Holzhacker C, Stöger B, Carvalho MD, Ferreira LP, Pittenauer E, Allmaier G, Veiros LF, Realista S, Gil A, Calhorda MJ, Müller D, Kirchner K. Synthesis and reactivity of TADDOL-based chiral Fe(II) PNP pincer complexes-solution equilibria between κ(2)P,N- and κ(3)P,N,P-bound PNP pincer ligands. Dalton Trans 2015; 44:13071-86. [PMID: 26104487 DOI: 10.1039/c5dt00832h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Treatment of anhydrous FeX2 (X = Cl, Br) with 1 equiv. of the asymmetric chiral PNP pincer ligands PNP-R,TAD (R = iPr, tBu) with an R,R-TADDOL (TAD) moiety afforded complexes of the general formula [Fe(PNP)X2]. In the solid state these complexes adopt a tetrahedral geometry with the PNP ligand coordinated in κ(2)P,N-fashion, as shown by X-ray crystallography and Mössbauer spectroscopy. Magnetization studies led to a magnetic moment very close to 4.9μB reflecting the expected four unpaired d-electrons (quintet ground state). In solution there are equilibria between [Fe(κ(3)P,N,P-PNP-R,TAD)X2] and [Fe(κ(2)P,N-PNP-R,TAD)X2] complexes, i.e., the PNP-R,TAD ligand is hemilabile. At -50 °C these equilibria are slow and signals of the non-coordinated P-TAD arm of the κ(2)P,N-PNP-R,TAD ligand can be detected by (31)P{(1)H} NMR spectroscopy. Addition of BH3 to a solution of [Fe(PNP-iPr,TAD)Cl2] leads to selective boronation of the pendant P-TAD arm shifting the equilibrium towards the four-coordinate complex [Fe(κ(2)P,N-PNP-iPr,TAD(BH3))Cl2]. DFT calculations corroborate the existence of equilibria between four- and five-coordinated complexes. Addition of CO to [Fe(PNP-iPr,TAD)X2] in solution yields the diamagnetic octahedral complexes trans-[Fe(κ(3)P,N,P-PNP-iPr,TAD)(CO)X2], which react further with Ag(+) salts in the presence of CO to give the cationic complexes trans-[Fe(κ(3)P,N,P-PNP-iPr,TAD)(CO)2X](+). CO addition most likely takes place at the five coordinate complex [Fe(κ(3)P,N,P-PNP-iPr,TAD)X2]. The mechanism for the CO addition was also investigated by DFT and the most favorable path obtained corresponds to the rearrangement of the pincer ligand first from a κ(2)P,N- to a κ(3)P,N,P-coordination mode followed by CO coordination to [Fe(κ(3)P,N,P-PNP-iPr,TAD)X2]. Complexes bearing tBu substituents do not react with CO. Moreover, in the solid state none of the tetrahedral complexes are able to bind CO.
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Affiliation(s)
- Christian Holzhacker
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9, A-1060 Vienna, Austria.
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16
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Mazza S, Scopelliti R, Hu X. Chemoselective Hydrogenation and Transfer Hydrogenation of Aldehydes Catalyzed by Iron(II) PONOP Pincer Complexes. Organometallics 2015. [DOI: 10.1021/acs.organomet.5b00105] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Simona Mazza
- Laboratory of Inorganic
Synthesis
and Catalysis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), ISCI-LSCI, BCH 3305, 1015 Lausanne, Switzerland
| | - Rosario Scopelliti
- Laboratory of Inorganic
Synthesis
and Catalysis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), ISCI-LSCI, BCH 3305, 1015 Lausanne, Switzerland
| | - Xile Hu
- Laboratory of Inorganic
Synthesis
and Catalysis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), ISCI-LSCI, BCH 3305, 1015 Lausanne, Switzerland
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Glatz M, Bichler B, Mastalir M, Stöger B, Weil M, Mereiter K, Pittenauer E, Allmaier G, Veiros LF, Kirchner K. Iron(ii) complexes featuring κ3- and κ2-bound PNP pincer ligands – the significance of sterics. Dalton Trans 2015; 44:281-94. [PMID: 25376759 DOI: 10.1039/c4dt02866j] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of octahedral Fe(ii) complexes of the type [Fe(κ3-P,N,P-PNP)(κ2-P,N-PNP)X]+ (X = Cl, Br) where PNP pincer ligands are coordinated both in a κ3-P,N,P- and κ2-P,N-fashion was prepared and characterized.
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Affiliation(s)
- Mathias Glatz
- Institute of Applied Synthetic Chemistry
- Vienna University of Technology
- A-1060 Vienna
- Austria
| | - Bernhard Bichler
- Institute of Applied Synthetic Chemistry
- Vienna University of Technology
- A-1060 Vienna
- Austria
| | - Matthias Mastalir
- Institute of Applied Synthetic Chemistry
- Vienna University of Technology
- A-1060 Vienna
- Austria
| | - Berthold Stöger
- Institute of Chemical Technologies and Analytics
- Vienna University of Technology
- A-1060 Vienna
- Austria
| | - Matthias Weil
- Institute of Chemical Technologies and Analytics
- Vienna University of Technology
- A-1060 Vienna
- Austria
| | - Kurt Mereiter
- Institute of Chemical Technologies and Analytics
- Vienna University of Technology
- A-1060 Vienna
- Austria
| | - Ernst Pittenauer
- Institute of Chemical Technologies and Analytics
- Vienna University of Technology
- A-1060 Vienna
- Austria
| | - Günter Allmaier
- Institute of Chemical Technologies and Analytics
- Vienna University of Technology
- A-1060 Vienna
- Austria
| | - Luis F. Veiros
- Centro de Química Estrutural
- Instituto Superior Técnico
- Universidade de Lisboa
- 1049-001 Lisboa
- Portugal
| | - Karl Kirchner
- Institute of Applied Synthetic Chemistry
- Vienna University of Technology
- A-1060 Vienna
- Austria
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