1
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Bienenmann RLM, de Vries MR, Lutz M, Broere DLJ. Understanding the Remarkable Stability of Well-Defined Dinuclear Copper(I) Carbene Complexes. Chemistry 2024; 30:e202400283. [PMID: 38630913 DOI: 10.1002/chem.202400283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 04/16/2024] [Accepted: 04/17/2024] [Indexed: 04/19/2024]
Abstract
The synthesis of a well-defined dicopper carbene complex supported by the PNNP (2,7-bis(di-tert-butylphosphaneyl)methyl-1,8-naphthyridine) expanded pincer ligand is reported. This carbene complex is remarkably stable, even in the presence of air and water. The reactivity of this complex was explored towards typical carbene transfer substrates and its electronic structure was investigated. Using a combination of experiments and DFT calculations, the principles that underly the stability of dinuclear carbene complexes are probed.
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Affiliation(s)
- Roel L M Bienenmann
- Organic Chemistry and Catalysis, Institute for Sustainable and Circular Chemistry, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
| | - Marianne R de Vries
- Organic Chemistry and Catalysis, Institute for Sustainable and Circular Chemistry, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
| | - Martin Lutz
- Structural Biochemistry, Bijvoet Centre for Biomolecular Research, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
| | - Daniël L J Broere
- Organic Chemistry and Catalysis, Institute for Sustainable and Circular Chemistry, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
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2
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See M, Ríos P, Tilley TD. Diborane Reductions of CO 2 and CS 2 Mediated by Dicopper μ-Boryl Complexes of a Robust Bis(phosphino)-1,8-naphthyridine Ligand. Organometallics 2024; 43:1180-1189. [PMID: 38817536 PMCID: PMC11134609 DOI: 10.1021/acs.organomet.4c00122] [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: 03/27/2024] [Revised: 04/12/2024] [Accepted: 04/19/2024] [Indexed: 06/01/2024]
Abstract
A dinucleating 1,8-naphthyridine ligand featuring fluorene-9,9-diyl-linked phosphino side arms (PNNPFlu) was synthesized and used to obtain the cationic dicopper complexes 2, [(PNNPFlu)Cu2(μ-Ph)][NTf2]; [NTf2] = bis(trifluoromethane)sulfonimide, 6, [(PNNPFlu)Cu2(μ-CCPh)][NTf2], and 3, [(PNNPFlu)Cu2(μ-OtBu)][NTf2]. Complex 3 reacted with diboranes to afford dicopper μ-boryl species (4, with μ-Bcat; cat = catecholate and 5, with μ-Bpin; pin = pinacolate) that are more reactive in C(sp)-H bond activations and toward activations of CO2 and CS2, compared to dicopper μ-boryl complexes supported by a 1,8-naphthyridine-based ligand with di(pyridyl) side arms. The solid-state structures and DFT analysis indicate that the higher reactivities of 4 and 5 relate to changes in the coordination sphere of copper, rather than to perturbations on the Cu-B bonding interactions. Addition of xylyl isocyanide (CNXyl) to 4 gave 7, [(PNNPFlu)Cu2(μ-Bcat)(CNXyl)][NTf2], demonstrating that the lower coordination number at copper is chemically significant. Reactions of 4 and 5 with CO2 yielded the corresponding dicopper borate complexes (8, [(PNNPFlu)Cu2(μ-OBcat)][NTf2]; 9, [(PNNPFlu)Cu2(μ-OBpin)][NTf2]), with 4 demonstrating catalytic reduction in the presence of excess diborane. Related reactions of 4 and 5 with CS2 provided insertion products 10, {[(PNNPFlu)Cu2]2[μ-S2C(Bcat)2]}[NTf2]2, and 11, [(PNNPFlu)Cu2(μ,κ2-S2CBpin)][NTf2], respectively. These products feature Cu-S-C-B linkages analogous to those of proposed CO2 insertion intermediate.
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Affiliation(s)
- Matthew
S. See
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Pablo Ríos
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
- Instituto
de Investigaciones Químicas (IIQ), Departamento de Química
Inorgánica, Centro de Innovación en Química Avanzada
(ORFEO−CINQA), CSIC and Universidad
de Sevilla, Sevilla 41092, Spain
| | - T. Don Tilley
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
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3
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Kounalis E, van Tongeren D, Melnikov S, Lutz M, Broere DLJ. Pendulum-like hemilability in a Ti-based frustrated Lewis Trio. Chem Sci 2024; 15:5555-5563. [PMID: 38638227 PMCID: PMC11023062 DOI: 10.1039/d3sc06789k] [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: 12/18/2023] [Accepted: 03/08/2024] [Indexed: 04/20/2024] Open
Abstract
We describe the first experimental example of a theoretically predicted Frustrated Lewis Trio (FLT). A tetradentate PNNP ligand is used to stabilise a highly electrophilic [TiCl3]+ fragment in a way that results in two equally long and frustrated Ti-P bonds. A combined experimental and computational approach revealed a distinct role of each Lewis basic phosphine in the heterolytic activation of chemical bonds. This dual functionality is characterised by a pendulum-like hemilability, where one of the phosphines acts as a nucleophile while the other serves as a hemilabile ligand that dynamically tunes the Ti-P distance as a function of the required electron density at the Ti centre.
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Affiliation(s)
- Errikos Kounalis
- Organic Chemistry and Catalysis, Institute for Sustainable and Circular Chemistry, Faculty of Science, Utrecht University, Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Dylan van Tongeren
- Organic Chemistry and Catalysis, Institute for Sustainable and Circular Chemistry, Faculty of Science, Utrecht University, Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Stanislav Melnikov
- Organic Chemistry and Catalysis, Institute for Sustainable and Circular Chemistry, Faculty of Science, Utrecht University, Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Martin Lutz
- Structural Biochemistry Bijvoet Centre for Biomolecular Research, Faculty of Science, Utrecht University, Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Daniël L J Broere
- Organic Chemistry and Catalysis, Institute for Sustainable and Circular Chemistry, Faculty of Science, Utrecht University, Universiteitsweg 99 3584 CG Utrecht The Netherlands
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4
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Abaeva M, Ieritano C, Hopkins WS, Schipper DJ. Unsymmetrical Imidazopyrimidine-Based Ligand and Bimetallic Complexes. Inorg Chem 2024; 63:1010-1019. [PMID: 38055895 DOI: 10.1021/acs.inorgchem.3c03062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
With bimetallic catalysts becoming increasingly important, the development of electronically and structurally diverse binucleating ligands is desired. This work describes the synthesis of unsymmetric ligand 2,7-di(pyridin-2-yl)imidazo[1,2-a]pyrimidine (dpip) that is achieved in four steps on a multigram scale in an overall 54% yield. The ability of dpip to act as a scaffold for the formation of bimetallic complexes is demonstrated with the one-step syntheses of the dicopper complex [Cu2(dpip)(μ-OH)(CF3COO)3] (4), the dipalladium complex [Pd2(dpip)(μ-OH)(CF3COO)2](CF3COO)·CF3COOH (5), and the dimeric dinickel complex [Ni4(dpip)2(μ-Cl)4Cl2MeOH6][2Cl] (6) in good yields (79-92%). All bimetallic complexes were characterized by spectroscopic methods and X-ray crystallography, which revealed metal-metal distances between 3.4821(9) and 4.106(2) Å. Additionally, quantum chemical calculations were conducted on complex 4 and an analogous 1,8-naphthyridine-based dicopper complex to investigate the differences between the imidazopyrimidine motif reported here and the widely used 1,8-naphthyridine motif. Natural bonding orbital (NBO) and Mayer bond order (MBO) analyses validated the ability of dpip to coordinate metals more strongly. Finally, NBO calculations quantified the differences in the binding energy between the two pockets of the unsymmetrical dpip ligand.
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Affiliation(s)
- Mila Abaeva
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Christian Ieritano
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- Watermine Innovation, Waterloo, Ontario N0B 2T0, Canada
| | - W Scott Hopkins
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- Watermine Innovation, Waterloo, Ontario N0B 2T0, Canada
| | - Derek J Schipper
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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5
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Multem AJH, Delaney AR, Kroeger AA, Coote ML, Colebatch AL. Utilising a Proton-Responsive 1,8-Naphthyridine Ligand for the Synthesis of Bimetallic Palladium and Platinum Complexes. Chem Asian J 2023:e202301071. [PMID: 38161148 DOI: 10.1002/asia.202301071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 12/20/2023] [Accepted: 12/25/2023] [Indexed: 01/03/2024]
Abstract
We present four proton-responsive palladium and platinum complexes, [MCl2 (R PONNHO)] (M=Pd, Pt; R=i Pr, t Bu) synthesised by complexation of PdCl2 or PtCl2 (COD) with the 1,8-naphthyridine ligand R PONNHO. Deprotonation of [MCl2 (tBu PONNHO)] switches ligand coordination from mono- to dinucleating, offering a synthetic pathway to bimetallic PdII and PtII complexes [M2 Cl2 (tBu PONNO)2 ]. Two-electron reduction gives planar MI -MI complexes [M2 (tBu PONNO)2 ] (M=Pd, Pt) containing a metal-metal bond. In contrast to the related nickel system that forms a metallophosphorane [Ni2 (tBu PONNOPONNO)], an unusual phosphinite binding mode is observed in [M2 (tBu PONNO)2 ] containing close phosphinite-naphthyridinone P⋅⋅⋅O interactions, which is investigated spectroscopically, crystallographically and computationally. The presented proton-responsive and structurally-responsive R PONNHO and bimetallic R PONNO complexes offer a novel platform for future explorations of metal-ligand and metal-metal cooperativity with palladium and platinum.
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Affiliation(s)
- Arie J H Multem
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
| | - Andie R Delaney
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
| | - Asja A Kroeger
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
- Institute for Nanoscale Science & Technology, Flinders University, Adelaide, South Australia, 5042, Australia
| | - Michelle L Coote
- Institute for Nanoscale Science & Technology, Flinders University, Adelaide, South Australia, 5042, Australia
| | - Annie L Colebatch
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
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6
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Iwamoto T, Sotome Y, Ishii Y. Binuclear Complexes Supported by a Tetrapyridyl Ligand with a Bending Anthraquinodimethane Linker. ACS ORGANIC & INORGANIC AU 2023; 3:305-311. [PMID: 37810407 PMCID: PMC10557120 DOI: 10.1021/acsorginorgau.3c00021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/28/2023] [Accepted: 07/31/2023] [Indexed: 10/10/2023]
Abstract
A tetrapyridyl ligand with a bending anthraquinodimethane linker has been synthesized, and its complexation with coinage metals has been examined. The treatment of the ligand with Ag(I) and Au(I) cations afforded binuclear complexes, wherein the two metal centers were in close proximity to the inside space of the ligand. X-ray analyses corroborated with theoretical calculations indicated that the ligand has reasonable flexibility toward a bending deformation of the linker moiety to provide a ligand pocket suitable for the proximal binuclear complexes, even though such deformations accompany a non-negligible amount of energetic cost. On the other hand, treatment with 2 equiv of Cu(I) salt afforded a binuclear complex, in which both copper atoms were coordinated at the periphery of the ligand.
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Affiliation(s)
- Takahiro Iwamoto
- Department of Applied Chemistry,
Faculty of Science and Engineering, Chuo
University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
| | - Yuta Sotome
- Department of Applied Chemistry,
Faculty of Science and Engineering, Chuo
University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
| | - Youichi Ishii
- Department of Applied Chemistry,
Faculty of Science and Engineering, Chuo
University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
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7
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Delaney AR, Yu LJ, Doan V, Coote ML, Colebatch AL. Bimetallic Nickel Complexes Supported by a Planar Macrocyclic Diphosphoranide Ligand. Chemistry 2023; 29:e202203940. [PMID: 36545819 DOI: 10.1002/chem.202203940] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 12/20/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022]
Abstract
Metal-metal cooperativity is emerging as an important strategy in catalysis. This requires appropriate ligand scaffolds that can support two metals in close proximity. Here we report nickel-promoted formation of a dinucleating planar macrocyclic ligand that can support bimetallic dinickel(II) and dinickel(I) complexes. Reaction outcomes can be tuned by variation of the substituents and reaction conditions to favour dinucleating macrocyclic, mononucleating macrocyclic or conventional pincer architectures.
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Affiliation(s)
- Andie R Delaney
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
| | - Li-Juan Yu
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
| | - Vincent Doan
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
| | - Michelle L Coote
- Institute for Nanoscale Science & Technology, Flinders University, Adelaide, South Australia, 5042, Australia
| | - Annie L Colebatch
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
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8
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Killian L, Bienenmann RLM, Broere DLJ. Quantification of the Steric Properties of 1,8-Naphthyridine-Based Ligands in Dinuclear Complexes. Organometallics 2023; 42:27-37. [PMID: 36644418 PMCID: PMC9832537 DOI: 10.1021/acs.organomet.2c00458] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Indexed: 12/03/2022]
Abstract
Steric properties of ligands are an important parameter for tuning the reactivity of the corresponding complexes. For various ligands used in mononuclear complexes, methods have been developed to quantify their steric bulk. In this work, we present an expansion of the buried volume and the G-parameter to quantify the steric properties of 1,8-napthyridine-based dinuclear complexes. Using this methodology, we explored the tunability of the steric properties associated with these ligands and complexes.
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9
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van Beek CB, Killian L, Lutz M, Weingarth M, Asundi AS, Sarangi R, Klein Gebbink RJM, Broere DLJ. E-selective Semi-hydrogenation of Alkynes under Mild Conditions by a Diruthenium Hydride Complex. Chemistry 2022; 28:e202202527. [PMID: 35979748 PMCID: PMC10092327 DOI: 10.1002/chem.202202527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Indexed: 12/14/2022]
Abstract
The synthesis, characterization and catalytic activity of a new class of diruthenium hydrido carbonyl complexes bound to the tBu PNNP expanded pincer ligand is described. Reacting tBu PNNP with two equiv of RuHCl(PPh3 )3 (CO) at 140 °C produces an insoluble air-stable complex, which was structurally characterized as [Ru2 (tBu PNNP)H(μ-H)Cl(μ-Cl)(CO)2 ] (1) using solid-state NMR, IR and X-ray absorption spectroscopies and follow-up reactivity. A reaction with KOtBu results in deprotonation of a methylene linker to produce [Ru2 (tBu PNNP* )H(μ-H)(μ-OtBu)(CO)2 ] (3) featuring a partially dearomatized naphthyridine core. This enables metal-ligand cooperative activation of H2 analogous to the mononuclear analogue, [Ru(tBu PNP*)H(CO)]. In contrast to the mononuclear system, the bimetallic analogue 3 catalyzes the E-selective semi-hydrogenation of alkynes at ambient temperature and atmospheric H2 pressure with good functional group tolerance. Monitoring the semi-hydrogenation of diphenylacetylene by 1 H NMR spectroscopy shows the intermediacy of Z-stilbene, which is subsequently isomerized to the E-isomer. Initial findings into the mode of action of this system are provided, including the spectroscopic characterization of a polyhydride intermediate and the isolation of a deactivated species with a partially hydrogenated naphthyridine backbone.
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Affiliation(s)
- Cody B van Beek
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht (The, Netherlands
| | - Lars Killian
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht (The, Netherlands
| | - Martin Lutz
- Structural Biochemistry, Bijvoet Centre for Biomolecular Research, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht (The, Netherlands
| | - Markus Weingarth
- NMR Spectroscopy, Bijvoet Centre for Biomolecular Research, Department of Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht (The, Netherlands
| | - Arun S Asundi
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, 94025, Menlo Park, California, USA
| | - Ritimukta Sarangi
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, 94025, Menlo Park, California, USA
| | - Robertus J M Klein Gebbink
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht (The, Netherlands
| | - Daniël L J Broere
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht (The, Netherlands
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10
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Govindarajan R, Deolka S, Khusnutdinova JR. Heterometallic bond activation enabled by unsymmetrical ligand scaffolds: bridging the opposites. Chem Sci 2022; 13:14008-14031. [PMID: 36540828 PMCID: PMC9728565 DOI: 10.1039/d2sc04263k] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 10/27/2022] [Indexed: 08/19/2023] Open
Abstract
Heterobi- and multimetallic complexes providing close proximity between several metal centers serve as active species in artificial and enzymatic catalysis, and in model systems, showing unique modes of metal-metal cooperative bond activation. Through the rational design of well-defined, unsymmetrical ligand scaffolds, we create a convenient approach to support the assembly of heterometallic species in a well-defined and site-specific manner, preventing them from scrambling and dissociation. In this perspective, we will outline general strategies for the design of unsymmetrical ligands to support heterobi- and multimetallic complexes that show reactivity in various types of heterometallic cooperative bond activation.
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Affiliation(s)
- R Govindarajan
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
| | - Shubham Deolka
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
| | - Julia R Khusnutdinova
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
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11
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Hall PD, Stevens MA, Wang JYJ, Pham LN, Coote ML, Colebatch AL. Copper and Zinc Complexes of 2,7-Bis(6-methyl-2-pyridyl)-1,8-naphthyridine─A Redox-Active, Dinucleating Bis(bipyridine) Ligand. Inorg Chem 2022; 61:19333-19343. [DOI: 10.1021/acs.inorgchem.2c03126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Peter D. Hall
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory2601, Australia
| | - Michael A. Stevens
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory2601, Australia
| | - Jiao Yu J. Wang
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory2601, Australia
| | - Le Nhan Pham
- Institute for Nanoscale Science & Technology, Flinders University, Adelaide, South Australia5042, Australia
| | - Michelle L. Coote
- Institute for Nanoscale Science & Technology, Flinders University, Adelaide, South Australia5042, Australia
| | - Annie L. Colebatch
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory2601, Australia
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12
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Bienenmann RLM, Schanz AJ, Ooms PL, Lutz M, Broere DLJ. A Well‐Defined Anionic Dicopper(I) Monohydride Complex that Reacts like a Cluster**. Angew Chem Int Ed Engl 2022; 61:e202202318. [PMID: 35412679 PMCID: PMC9400846 DOI: 10.1002/anie.202202318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Indexed: 11/08/2022]
Abstract
Low‐nuclearity copper hydrides are rare and few well‐defined dicopper hydrides have been reported. Herein, we describe the first example of a structurally characterized anionic dicopper hydride complex. This complex does not display typical reactivity associated with low‐nuclearity copper hydrides, such as alcoholysis or insertion reactions. Instead, its stoichiometric and catalytic reactivity is akin to that of copper hydride clusters. The distinct reactivity is ascribed to the robust dinuclear core that is bound tightly within the dinucleating ligand scaffold.
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Affiliation(s)
- Roel L. M. Bienenmann
- Organic Chemistry and Catalysis Debye Institute for Nanomaterials Science Faculty of Science Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Alexandra J. Schanz
- Organic Chemistry and Catalysis Debye Institute for Nanomaterials Science Faculty of Science Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Pascale L. Ooms
- Organic Chemistry and Catalysis Debye Institute for Nanomaterials Science Faculty of Science Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Martin Lutz
- Structural Biochemistry Bijvoet Centre for Biomolecular Research Faculty of Science Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Daniël L. J. Broere
- Organic Chemistry and Catalysis Debye Institute for Nanomaterials Science Faculty of Science Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
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13
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Ríos P, See MS, Handford RC, Teat SJ, Tilley TD. Robust dicopper(i) μ-boryl complexes supported by a dinucleating naphthyridine-based ligand. Chem Sci 2022; 13:6619-6625. [PMID: 35756530 PMCID: PMC9172574 DOI: 10.1039/d2sc00848c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 05/05/2022] [Indexed: 12/11/2022] Open
Abstract
Copper boryl species have been widely invoked as reactive intermediates in Cu-catalysed C–H borylation reactions, but their isolation and study have been challenging. Use of the robust dinucleating ligand DPFN (2,7-bis(fluoro-di(2-pyridyl)methyl)-1,8-naphthyridine) allowed for the isolation of two very thermally stable dicopper(i) boryl complexes, [(DPFN)Cu2(μ-Bpin)][NTf2] (2) and [(DPFN)Cu2(μ-Bcat)][NTf2] (4) (pin = 2,3-dimethylbutane-2,3-diol; cat = benzene-1,2-diol). These complexes were prepared by cleavage of the corresponding diborane via reaction with the alkoxide [(DPFN)Cu2(μ-OtBu)][NTf2] (3). Reactivity studies illustrated the exceptional stability of these boryl complexes (thermal stability in solution up to 100 °C) and their role in the activation of C(sp)–H bonds. X-ray diffraction and computational studies provide a detailed description of the bonding and electronic structures in these complexes, and suggest that the dinucleating character of the naphthyridine-based ligand is largely responsible for their remarkable stability. Cu(i) boryl species have been widely invoked as reactive intermediates in Cu-catalysed C–H borylations, but their isolation has been challenging. In this work, thermally robust dicopper(I) boryl complexes have been synthesized and studied in detail.![]()
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Affiliation(s)
- Pablo Ríos
- Department of Chemistry, University of California Berkeley USA
| | - Matthew S See
- Department of Chemistry, University of California Berkeley USA
| | - Rex C Handford
- Department of Chemistry, University of California Berkeley USA
| | - Simon J Teat
- Advanced Light Source, Lawrence Berkeley National Laboratory Berkeley CA 94720-1460 USA
| | - T Don Tilley
- Department of Chemistry, University of California Berkeley USA
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14
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van Beek CB, Killian L, Lutz M, Broere D. Persistence of a Ru3( µ ‐CO)3(CO)5 cluster bound to a PNNP ‘expanded pincer’ ligand in different protonation states. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Lars Killian
- Utrecht University: Universiteit Utrecht Chemistry NETHERLANDS
| | - Martin Lutz
- Utrecht University: Universiteit Utrecht Chemistry NETHERLANDS
| | - Daniel Broere
- Universiteit Utrecht Faculteit Betawetenschappen Chemistry Universiteitsweg 99 3584 CG Utrecht NETHERLANDS
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15
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Bienenmann RLM, Schanz AJ, Ooms PL, Lutz M, Broere DLJ. A Well‐Defined Anionic Dicopper(I) Monohydride Complex that Reacts like a Cluster**. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202202318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Roel L. M. Bienenmann
- Organic Chemistry and Catalysis Debye Institute for Nanomaterials Science Faculty of Science Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Alexandra J. Schanz
- Organic Chemistry and Catalysis Debye Institute for Nanomaterials Science Faculty of Science Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Pascale L. Ooms
- Organic Chemistry and Catalysis Debye Institute for Nanomaterials Science Faculty of Science Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Martin Lutz
- Structural Biochemistry Bijvoet Centre for Biomolecular Research Faculty of Science Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Daniël L. J. Broere
- Organic Chemistry and Catalysis Debye Institute for Nanomaterials Science Faculty of Science Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
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16
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Liu CY, Yuan SF, Wang S, Guan ZJ, Jiang DE, Wang QM. Structural transformation and catalytic hydrogenation activity of amidinate-protected copper hydride clusters. Nat Commun 2022; 13:2082. [PMID: 35440582 PMCID: PMC9018778 DOI: 10.1038/s41467-022-29819-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 03/22/2022] [Indexed: 02/06/2023] Open
Abstract
Copper hydrides are important hydrogenation catalysts, but their poor stability hinders the practical applications. Ligand engineering is an effective strategy to tackle this issue. An amidinate ligand, N,N'-Di(5-trifluoromethyl-2-pyridyl)formamidinate (Tf-dpf) with four N-donors has been applied as a protecting agent in the synthesis of stable copper hydride clusters: Cu11H3(Tf-dpf)6(OAc)2 (Cu11) with three interfacial μ5-H and [Cu12H3(Tf-dpf)6(OAc)2]·OAc (Cu12) with three interstitial μ6-H. A solvent-triggered reversible interconversion between Cu11 and Cu12 has been observed thanks to the flexibility of Tf-dpf. Cu11 shows high activity in the reduction of 4-nitrophenol to 4-aminophenol, while Cu12 displays very low activity. Deuteration experiments prove that the type of hydride is the key in dictating the catalytic activity, for the interfacial μ5-H species in Cu11 are involved in the catalytic cycle whereas the interstitial μ6-H species in Cu12 are not. This work highlights the role of hydrides with regard to catalytic hydrogenation activity.
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Affiliation(s)
- Chun-Yu Liu
- Department of Chemistry, Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Tsinghua University, 10084, Beijing, PR China
| | - Shang-Fu Yuan
- Department of Chemistry, Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Tsinghua University, 10084, Beijing, PR China
| | - Song Wang
- Department of Chemistry, University of California, Riverside, CA, 92521, USA
| | - Zong-Jie Guan
- Department of Chemistry, Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Tsinghua University, 10084, Beijing, PR China
| | - De-En Jiang
- Department of Chemistry, University of California, Riverside, CA, 92521, USA
| | - Quan-Ming Wang
- Department of Chemistry, Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Tsinghua University, 10084, Beijing, PR China.
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17
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Stevens MA, Colebatch AL. Cooperative approaches in catalytic hydrogenation and dehydrogenation. Chem Soc Rev 2022; 51:1881-1898. [PMID: 35230366 DOI: 10.1039/d1cs01171e] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Metal-ligand cooperativity (MLC) is an established strategy for developing effective hydrogenation and dehydrogenation catalysts. Metal-metal cooperativity (MMC) in bimetallic complexes is not as well understood, and to date has had limited implementation in (de)hydrogenation. Herein we use (de)hydrogenation processes as a platform to examine modes of cooperativity, with a particular focus on catalytic mechanisms. We investigate how lessons learnt from the extensive development of metal-ligand cooperative catalysts can aid the ongoing development of metal-metal cooperative catalysts.
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Affiliation(s)
- Michael A Stevens
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia.
| | - Annie L Colebatch
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia.
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18
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van Beek CB, van Leest NP, Lutz M, de Vos SD, Klein Gebbink RJM, de Bruin B, Broere DLJ. Combining metal-metal cooperativity, metal-ligand cooperativity and chemical non-innocence in diiron carbonyl complexes. Chem Sci 2022; 13:2094-2104. [PMID: 35308864 PMCID: PMC8849050 DOI: 10.1039/d1sc05473b] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 01/11/2022] [Indexed: 02/06/2023] Open
Abstract
Several metalloenzymes, including [FeFe]-hydrogenase, employ cofactors wherein multiple metal atoms work together with surrounding ligands that mediate heterolytic and concerted proton-electron transfer (CPET) bond activation steps. Herein, we report a new dinucleating PNNP expanded pincer ligand, which can bind two low-valent iron atoms in close proximity to enable metal-metal cooperativity (MMC). In addition, reversible partial dearomatization of the ligand's naphthyridine core enables both heterolytic metal-ligand cooperativity (MLC) and chemical non-innocence through CPET steps. Thermochemical and computational studies show how a change in ligand binding mode can lower the bond dissociation free energy of ligand C(sp3)-H bonds by ∼25 kcal mol-1. H-atom abstraction enabled trapping of an unstable intermediate, which undergoes facile loss of two carbonyl ligands to form an unusual paramagnetic (S = ) complex containing a mixed-valent iron(0)-iron(i) core bound within a partially dearomatized PNNP ligand. Finally, cyclic voltammetry experiments showed that these diiron complexes show catalytic activity for the electrochemical hydrogen evolution reaction. This work presents the first example of a ligand system that enables MMC, heterolytic MLC and chemical non-innocence, thereby providing important insights and opportunities for the development of bimetallic systems that exploit these features to enable new (catalytic) reactivity.
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Affiliation(s)
- Cody B van Beek
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Nicolaas P van Leest
- Homogeneous, Supramolecular and Bio-Inspired Catalysis Group, Van 't Hoff Institute for Molecular Sciences, University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
| | - Martin Lutz
- Structural Biochemistry, Bijvoet Centre for Biomolecular Research, Faculty of Science, Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Sander D de Vos
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Robertus J M Klein Gebbink
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
| | - Bas de Bruin
- Homogeneous, Supramolecular and Bio-Inspired Catalysis Group, Van 't Hoff Institute for Molecular Sciences, University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands
| | - Daniël L J Broere
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University Universiteitsweg 99 3584 CG Utrecht The Netherlands
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19
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Isegawa M, Matsumoto T, Ogo S. Hydrogen evolution, electron-transfer, and hydride-transfer reactions in a nickel-iron hydrogenase model complex: a theoretical study of the distinctive reactivities for the conformational isomers of nickel-iron hydride. Dalton Trans 2021; 51:312-323. [PMID: 34897337 DOI: 10.1039/d1dt03582g] [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
Hydrogen fuel is a promising alternative to fossil fuel. Therefore, efficient hydrogen production is crucial to elucidate the distinctive reactivities of metal hydride species, the intermediates formed during hydrogen activation/evolution in the presence of organometallic catalysts. This study uses density functional theory (DFT) to investigate the isomerizations and reactivities of three nickel-iron (NiFe) hydride isomers synthesized by mimicking the active center of NiFe hydrogenase. Hydride transfer within these complexes, rather than a chemical reaction between the complexes, converts the three hydrides internally. Their reactivities, including their electron-transfer, hydride-transfer and proton-transfer reactions, are investigated. The bridging hydride complex exhibits a higher energy level for the highest occupied molecular orbital (HOMO) than the terminal hydride during the electron-transfer reaction. This energy level indicates that the bridging hydride is more easily oxidized and is more susceptible to electron transfer than the terminal hydride. Regarding the hydride-transfer reaction between the NiFe hydride complex and methylene blue, the terminal hydrides exhibit larger hydricity and lower reaction barriers than the bridging hydride complexes. The results of energy decomposition analysis indicate that the structural deformation energy of the terminal hydride in the transition state is smaller than that of the bridging hydride complex, which lowers the reaction barrier of hydride transfer in the terminal hydride. To produce hydrogen, the rate-determining step is represented by the protonation of the hydride, and the terminal hydrides are thermodynamically and kinetically superior to the bridging ones. The differences in the reactivities of the hydride isomers ensure the precise control of hydrogen, and the theoretical calculations can be applied to design catalysts for hydrogen activation/production.
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Affiliation(s)
- Miho Isegawa
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan.
| | - Takahiro Matsumoto
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan.
| | - Seiji Ogo
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan.
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20
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Lee K, Thomas CM. Nickel-Templated Replacement of Phosphine Substituents in a Tetradentate Bis(amido)bis(phosphine) Ligand. Inorg Chem 2021; 60:17348-17356. [PMID: 34709799 DOI: 10.1021/acs.inorgchem.1c02750] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The replacement of phosphine substituents in nickel-bound PNNP ligands is reported as an alternative method for preparing multidentate phosphine ligands with alkyl substituents. Treatment of the previously reported bis(phosphide) complex {K(THF)x}22Ph[PNNP]Ni (2) with 2 equiv of MeI, iPrI, and 1,3-dibromoethane formed alkyl-substituted complexes 2Ph,2Me[PNNP]Ni (3), 2Ph,2iPr[PNNP]Ni (4), and 2Ph,propylene[PNNP]Ni (5), respectively. The stereoselectivity (racemic vs meso) of these reactions can be controlled by varying the reaction temperature. The racemic mixtures of products with the new alkyl substituents in an anti configuration were favored at lower temperatures, whereas a larger proportion of meso compounds was acquired at higher temperatures. Further treatment of 3 with KH resulted in selective elimination of the remaining phenyl groups rather than the methyl substituents, affording bis(methylphosphide) complex {K(THF)x}22Me[PNNP]Ni (6). Subsequent treatment of 6 with additional MeI formed 4Me[PNNP]Ni (7), in which all four phenyl groups were replaced with methyl substituents. As a proof of concept, demetalation of the ligand from 7 was achieved using aqueous KCN to form a free dimethylphosphine-substituted ligand H24Me[PNNP] (8), and 8 was subsequently coordinated to a different metal, using PdCl2 to form 4Me[PNNP]Pd (9). Unlike the clean elimination of phenyl substituents from 3, the reactions of KH with 4 and 5 exhibited competitive elimination of both alkyl and phenyl substituents and/or attenuated reactivity.
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Affiliation(s)
- Kyounghoon Lee
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Christine M Thomas
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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21
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Cui J, Dietz M, Härterich M, Fantuzzi F, Lu W, Dewhurst RD, Braunschweig H. Diphosphino-Functionalized 1,8-Naphthyridines: a Multifaceted Ligand Platform for Boranes and Diboranes. Chemistry 2021; 27:15751-15756. [PMID: 34545966 PMCID: PMC9292315 DOI: 10.1002/chem.202102721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Indexed: 12/25/2022]
Abstract
A 1,8‐naphthyridine diphosphine (NDP) reacts with boron‐containing Lewis acids to generate complexes featuring a number of different naphthyridine bonding modes. When exposed to diborane B2Br4, NDP underwent self‐deprotonation to afford [NDP‐B2Br3]Br, an unsymmetrical diborane comprised of four fused rings. The reaction of two equivalents of monoborane BBr3 and NDP in a non‐polar solvent provided the simple phosphine‐borane adduct [NDP(BBr3)2], which then underwent intramolecular halide abstraction to furnish the salt [NDP‐BBr2][BBr4], featuring a different coordination mode from that of [NDP‐B2Br3]Br. Direct deprotonation of NDP by KHMDS or PhCH2K generates mono‐ and dipotassium reagents, respectively. The monopotassium reagent reacts with one or half an equivalent of B2(NMe2)2Cl2 to afford NDP‐based diboranes with three or four amino substituents.
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Affiliation(s)
- Jingjing Cui
- School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan, 430205, P. R. China.,Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Maximilian Dietz
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Marcel Härterich
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Felipe Fantuzzi
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Physical and Theoretical Chemistry, Julius-Maximilians-Universität Würzburg, Emil-Fischer-Str. 42, 97074, Würzburg, Germany
| | - Wei Lu
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Rian D Dewhurst
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
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22
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Rivada-Wheelaghan O, Deolka S, Govindarajan R, Khaskin E, Fayzullin RR, Pal S, Khusnutdinova JR. Construction of modular Pd/Cu multimetallic chains via ligand- and anion-controlled metal-metal interactions. Chem Commun (Camb) 2021; 57:10206-10209. [PMID: 34523650 DOI: 10.1039/d1cc04212b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The presence of Pd⋯Cu and Pd⋯Pd interactions as well as the order of metal atoms in a chain held by a modular polynucleating ligand is controlled by the coordinating ability of the anions, leading to selective formation of bi- and tetranuclear Pd/Cu and Pd4 chains. Metal-metal cooperative reactivity in these complexes was tested in Ar-O bond formation and alkyne activation.
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Affiliation(s)
- Orestes Rivada-Wheelaghan
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| | - Shubham Deolka
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| | - Ramadoss Govindarajan
- 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, FRC Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, Kazan 420088, Russian Federation
| | - Shrinwantu Pal
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - 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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23
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Stevens MA, Hall PD, Colebatch AL. Monometallic and Multimetallic Zinc Complexes of 2,7-Bis(2-pyridyl)-1,8-naphthyridine. Aust J Chem 2021. [DOI: 10.1071/ch21129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A series of zinc complexes of 2,7-bis(2-pyridyl)-1,8-naphthyridine (BPNP) has been synthesised and characterised by single crystal X-ray diffraction and solution state NMR spectroscopic studies. Reactions of BPNP with zinc acetate and zinc chloride were found to give mononuclear complexes of the form [Zn(BPNP)X2] (X = OAc, Cl), whereas reactions with zinc triflate led to a mixture of products. Several of these were identified crystallographically as [Zn(BPNP-H)(H2O)4](OTf)3 and [Zn(BPNP-H)(NCMe)(OTf)2]OTf, in which protonation of one pyridyl group occurred, and the dimeric species [Zn2(BPNP)4(μ-H2O)2](OTf)4. A trimetallic complex [Zn3(μ2-BPNP)(μ2-OAc)3(OAc)2(μ3-OH)] was also isolated from reactions involving zinc acetate, and demonstrates the ability of BPNP to coordinate two zinc atoms in the adjacent binding pockets.
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24
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Delaney AR, Yu LJ, Coote ML, Colebatch AL. Synthesis of an expanded pincer ligand and its bimetallic coinage metal complexes. Dalton Trans 2021; 50:11909-11917. [PMID: 34374394 DOI: 10.1039/d1dt01741a] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An expanded pincer ligand tBu-PONNOP (2,7-bis(di-tert-butylphosphinito)-1,8-naphthyridine) has been synthesised and its coordination to coinage metals has been studied. Bimetallic complexes were produced with metal halide salts of the type [M2X2(tBu-PONNOP)] (X = Cl, M = Au, Ag, Cu; X = I, M = Cu) with a varying degree of interaction with the naphthyridyl backbone in the order Au < Ag < Cu. The salts [Ag2(tBu-PONNOP)2][BArF4]2 (ArF = 3,5-C6H3(CF3)2) and [Ag2(NCMe)2(tBu-PONNOP)]X2 (X = BArF4, PF6) were prepared, which may serve as a source of tBu-PONNOP via transmetallation.
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Affiliation(s)
- Andie R Delaney
- Research School of Chemistry, The Australian National University, Canberra, ACT 2601, Australia.
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25
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Aloisi A, Crochet É, Nicolas E, Berthet JC, Lescot C, Thuéry P, Cantat T. Copper–Ligand Cooperativity in H2 Activation Enables the Synthesis of Copper Hydride Complexes. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00212] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alicia Aloisi
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette, France
| | - Étienne Crochet
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette, France
| | - Emmanuel Nicolas
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette, France
| | | | - Camille Lescot
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette, France
| | - Pierre Thuéry
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette, France
| | - Thibault Cantat
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette, France
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26
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Nicolay A, Héron J, Shin C, Kuramarohit S, Ziegler MS, Balcells D, Tilley TD. Unsymmetrical Naphthyridine-Based Dicopper(I) Complexes: Synthesis, Stability, and Carbon–Hydrogen Bond Activations. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00188] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Amélie Nicolay
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Julie Héron
- Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway
| | - Chungkeun Shin
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
| | - Serene Kuramarohit
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
| | - Micah S. Ziegler
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - David Balcells
- Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway
| | - T. Don Tilley
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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27
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Wang Q, Brooks SH, Liu T, Tomson NC. Tuning metal-metal interactions for cooperative small molecule activation. Chem Commun (Camb) 2021; 57:2839-2853. [PMID: 33624638 PMCID: PMC8274379 DOI: 10.1039/d0cc07721f] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cluster complexes have attracted interest for decades due to their promise of drawing analogies to metallic surfaces and metalloenzyme active sites, but only recently have chemists started to develop ligand scaffolds that are specifically designed to support multinuclear transition metal cores. Such ligands not only hold multiple metal centers in close proximity but also allow for fine-tuning of their electronic structures and surrounding steric environments. This Feature Article highlights ligand designs that allow for cooperative small molecule activation at cluster complexes, with a particular focus on complexes that contain metal-metal bonds. Two useful ligand-design elements have emerged from this work: a degree of geometric flexibility, which allows for novel small molecule activation modes, and the use of redox-active ligands to provide electronic flexibility to the cluster core. The authors have incorporated these factors into a unique class of dinucleating macrocycles (nPDI2). Redox-active fragments in nPDI2 mimic the weak-overlap covalent bonding that is characteristic of M-M interactions, and aliphatic linkers in the ligand backbone provide geometric flexibility, allowing for interconversion between a range of geometries as the dinuclear core responds to the requirements of various small molecule substrates. The union of these design elements appears to be a powerful combination for analogizing critical aspects of heterogeneous and metalloenzyme catalysts.
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Affiliation(s)
- Qiuran Wang
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104, USA.
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28
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Desnoyer AN, Nicolay A, Rios P, Ziegler MS, Tilley TD. Bimetallics in a Nutshell: Complexes Supported by Chelating Naphthyridine-Based Ligands. Acc Chem Res 2020; 53:1944-1956. [PMID: 32878429 DOI: 10.1021/acs.accounts.0c00382] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Bimetallic motifs are a structural feature common to some of the most effective and synthetically useful catalysts known, including in the active sites of many metalloenzymes and on the surfaces of industrially relevant heterogeneous materials. However, the complexity of these systems often hampers detailed studies of their fundamental properties. To glean valuable mechanistic insight into how these catalysts function, this research group has prepared a family of dinucleating 1,8-naphthyridine ligands that bind two first-row transition metals in close proximity, originally designed to help mimic the proposed active site of metal oxide surfaces. Of the various bimetallic combinations examined, dicopper(I) is particularly versatile, as neutral bridging ligands adopt a variety of different binding modes depending on the configuration of frontier orbitals available to interact with the Cu centers. Organodicopper complexes are readily accessible, either through the traditional route of salt metathesis or via the activation of tetraarylborate anions through aryl group abstraction by a dicopper(I) unit. The resulting bridging aryl complexes engage in C-H bond activations, notably with terminal alkynes to afford bridging alkynyl species. The μ-hydrocarbyl complexes are surprisingly tolerant of water and elevated temperatures. This stability was leveraged to isolate a species that typically represents a fleeting intermediate in Cu-catalyzed azide-alkyne coupling (CuAAC); reaction of a bridging alkynyl complex with an organic azide afforded the first example of a well-defined, symmetrically bridged dicopper triazolide. This complex was shown to be an intermediate during CuAAC, providing support for a proposed bimetallic mechanism. These platforms are not limited to formally low oxidation states; chemical oxidation of the hydrocarbyl complexes cleanly results in formation of mixed valence CuICuII complexes with varying degrees of distortion in both the bridging moiety and the dicopper core. Higher oxidation states, e.g., dicopper(II), are easily accessed via oxidation of a dicopper(I) compound with air to give a CuII2(μ-OH)2 complex. Reduction of this compound with silanes resulted in the unexpected formation of pentametallic copper(I) dihydride clusters or trimetallic monohydride complexes, depending on the nature of the silane. Finally, development of an unsymmetrical naphthyridine ligand with mixed donor side-arms enables selective synthesis of an isostructural series of six heterobimetallic complexes, demonstrating the power of ligand design in the preparation of heterometallic assemblies.
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Affiliation(s)
- Addison N. Desnoyer
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Amélie Nicolay
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Pablo Rios
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States
| | - Micah S. Ziegler
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - T. Don Tilley
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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Ekanayake DA, Chakraborty A, Krause JA, Guan H. Steric Effects of HN(CH2CH2PR2)2 on the Nuclearity of Copper Hydrides. Inorg Chem 2020; 59:12817-12828. [DOI: 10.1021/acs.inorgchem.0c01865] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Dewmi A. Ekanayake
- Department of Chemistry, University of Cincinnati, P.O. Box 210172, Cincinnati, Ohio 45221-0172, United States
| | - Arundhoti Chakraborty
- 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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30
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Scheerder AR, Lutz M, Broere DLJ. Unexpected reactivity of a PONNOP 'expanded pincer' ligand. Chem Commun (Camb) 2020; 56:8198-8201. [PMID: 32395727 DOI: 10.1039/d0cc02166k] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the synthesis, characterization and coordination chemistry of a new naphthyridine-derived phosphinite PONNOP expanded pincer ligand. As envisioned, the dinucleating ligand readily binds two copper(i) centers in close proximity, but undergoes an unexpected rearrangement in the presence of nickel(ii) salts to form an interesting PONNP pincer platform.
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Affiliation(s)
- Arthur R Scheerder
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands.
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Desnoyer AN, Nicolay A, Ziegler MS, Torquato NA, Tilley TD. A Dicopper Platform that Stabilizes the Formation of Pentanuclear Coinage Metal Hydride Complexes. Angew Chem Int Ed Engl 2020; 59:12769-12773. [DOI: 10.1002/anie.202004346] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Indexed: 11/05/2022]
Affiliation(s)
- Addison N. Desnoyer
- Department of Chemistry University of California, Berkeley Berkeley CA 94720-1460 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Amélie Nicolay
- Department of Chemistry University of California, Berkeley Berkeley CA 94720-1460 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Micah S. Ziegler
- Department of Chemistry University of California, Berkeley Berkeley CA 94720-1460 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Nicole A. Torquato
- Department of Chemistry University of California, Berkeley Berkeley CA 94720-1460 USA
| | - T. Don Tilley
- Department of Chemistry University of California, Berkeley Berkeley CA 94720-1460 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
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32
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Desnoyer AN, Nicolay A, Ziegler MS, Torquato NA, Tilley TD. A Dicopper Platform that Stabilizes the Formation of Pentanuclear Coinage Metal Hydride Complexes. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202004346] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Addison N. Desnoyer
- Department of Chemistry University of California, Berkeley Berkeley CA 94720-1460 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Amélie Nicolay
- Department of Chemistry University of California, Berkeley Berkeley CA 94720-1460 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Micah S. Ziegler
- Department of Chemistry University of California, Berkeley Berkeley CA 94720-1460 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Nicole A. Torquato
- Department of Chemistry University of California, Berkeley Berkeley CA 94720-1460 USA
| | - T. Don Tilley
- Department of Chemistry University of California, Berkeley Berkeley CA 94720-1460 USA
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
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33
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Deolka S, Rivada-Wheelaghan O, Aristizábal SL, Fayzullin RR, Pal S, Nozaki K, Khaskin E, Khusnutdinova JR. Metal-metal cooperative bond activation by heterobimetallic alkyl, aryl, and acetylide Pt II/Cu I complexes. Chem Sci 2020; 11:5494-5502. [PMID: 34094076 PMCID: PMC8159365 DOI: 10.1039/d0sc00646g] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
We report the selective formation of heterobimetallic PtII/CuI complexes that demonstrate how facile bond activation processes can be achieved by altering the reactivity of common organoplatinum compounds through their interaction with another metal center. The interaction of the Cu center with the Pt center and with a Pt-bound alkyl group increases the stability of PtMe2 towards undesired rollover cyclometalation. The presence of the CuI center also enables facile transmetalation from an electron-deficient tetraarylborate [B(ArF)4]− anion and mild C–H bond cleavage of a terminal alkyne, which was not observed in the absence of an electrophilic Cu center. The DFT study indicates that the Cu center acts as a binding site for the alkyne substrate, while activating its terminal C–H bond. The selective formation of heterobimetallic PtII/CuI complexes demonstrates how facile bond activation processes can be achieved by altering the reactivity of common organoplatinum compounds through their interaction with another metal center.![]()
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Affiliation(s)
- Shubham Deolka
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
| | - Orestes Rivada-Wheelaghan
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
| | - Sandra L Aristizábal
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
| | - Robert R Fayzullin
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences 8 Arbuzov Street Kazan 420088 Russian Federation
| | - Shrinwantu Pal
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo 7-3-1 Hongo, Bunkyo-ku Tokyo 113-8656 Japan
| | - Kyoko Nozaki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo 7-3-1 Hongo, Bunkyo-ku Tokyo 113-8656 Japan
| | - Eugene Khaskin
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
| | - Julia R Khusnutdinova
- Coordination Chemistry and Catalysis Unit, Okinawa Institute of Science and Technology Graduate University 1919-1 Tancha, Onna-son 904-0495 Okinawa Japan
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34
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Kounalis E, Lutz M, Broere DLJ. Tuning the Bonding of a μ-Mesityl Ligand on Dicopper(I) through a Proton-Responsive Expanded PNNP Pincer Ligand. Organometallics 2020. [DOI: 10.1021/acs.organomet.9b00829] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Errikos Kounalis
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science Faculty of Science, Utrecht University Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Martin Lutz
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research Faculty of Science, Utrecht University Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Daniël L. J. Broere
- Organic Chemistry and Catalysis, Debye Institute for Nanomaterials Science Faculty of Science, Utrecht University Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
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Kounalis E, Lutz M, Broere DLJ. Cooperative H 2 Activation on Dicopper(I) Facilitated by Reversible Dearomatization of an "Expanded PNNP Pincer" Ligand. Chemistry 2019; 25:13280-13284. [PMID: 31424132 PMCID: PMC6856846 DOI: 10.1002/chem.201903724] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Indexed: 02/06/2023]
Abstract
A naphthyridine-derived expanded pincer ligand is described that can host two copper(I) centers. The proton-responsive ligand can undergo reversible partial and full dearomatization of the naphthyridine core, which enables cooperative activation of H2 giving an unusual butterfly-shaped Cu4 H2 complex.
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Affiliation(s)
- Errikos Kounalis
- Organic Chemistry and CatalysisDebye Institute for Nanomaterials ScienceFaculty of ScienceUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| | - Martin Lutz
- Crystal and Structural ChemistryBijvoet Center for Biomolecular ResearchFaculty of ScienceUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
| | - Daniël L. J. Broere
- Organic Chemistry and CatalysisDebye Institute for Nanomaterials ScienceFaculty of ScienceUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
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