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Luo J, Montag M, Milstein D. Metal-Ligand Cooperation with Thiols as Transient Cooperative Ligands: Acceleration and Inhibition Effects in (De)Hydrogenation Reactions. Acc Chem Res 2024; 57:1709-1721. [PMID: 38833580 PMCID: PMC11191399 DOI: 10.1021/acs.accounts.4c00198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/13/2024] [Accepted: 05/15/2024] [Indexed: 06/06/2024]
Abstract
ConspectusOver the past two decades, we have developed a series of pincer-type transition metal complexes capable of activating strong covalent bonds through a mode of reactivity known as metal-ligand cooperation (MLC). In such systems, an incoming substrate molecule simultaneously interacts with both the metal center and ligand backbone, with one part of the molecule reacting at the metal center and another part at the ligand. The majority of these complexes feature pincer ligands with a pyridine core, and undergo MLC through reversible dearomatization/aromatization of this pyridine moiety. This MLC platform has enabled us to perform a variety of catalytic dehydrogenation, hydrogenation, and related reactions, with high efficiency and selectivity under relatively mild conditions.In a typical catalytic complex that operates through MLC, the cooperative ligand remains coordinated to the metal center throughout the entire catalytic process, and this complex is the only catalytic species involved in the reaction. As part of our ongoing efforts to develop new catalytic systems featuring MLC, we have recently introduced the concept of transient cooperative ligand (TCL), i.e., a ligand that is capable of MLC when coordinated to a metal center, but the coordination of which is reversible rather than permanent. We have thus far employed thiol(ate)s as TCLs, in conjunction with an acridanide-based ruthenium(II)-pincer catalyst, and this has resulted in remarkable acceleration and inhibition effects in various hydrogenation and dehydrogenation reactions. A cooperative thiol(ate) ligand can be installed in situ by the simple addition of an appropriate thiol in an amount equivalent to the catalyst, and this has been repeatedly shown to enable efficient bond activation by MLC without the need for other additives, such as base. The use of an ancillary thiol ligand that is not fixed to the pincer backbone allows the catalytic system to benefit from a high degree of tunability, easily implemented by varying the added thiol. Importantly, thiols are coordinatively labile enough under typical catalytic conditions to leave a meaningful portion of the catalyst in its original unsaturated form, thereby allowing it to carry out its own characteristic catalytic activity. This generates two coexisting catalyst populations─one that contains a thiol(ate) ligand and another that does not─and this may lead to different catalytic outcomes, namely, enhancement of the original catalytic activity, inhibition of this activity, or the occurrence of diverging reactivities within the same catalytic reaction mixture. These thiol effects have enabled us to achieve a series of unique transformations, such as thiol-accelerated base-free aqueous methanol reforming, controlled stereodivergent semihydrogenation of alkynes using thiol as a reversible catalyst inhibitor, and hydrogenative perdeuteration of C═C bonds without using D2, enabled by a combination of thiol-induced acceleration and inhibition. We have also successfully realized the unprecedented formation of thioesters through dehydrogenative coupling of alcohols and thiols, as well as the hydrogenation of organosulfur compounds, wherein the cooperative thiol serves as a reactant or product. In this Account, we present an overview of the TCL concept and its various applications using thiols.
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Affiliation(s)
- Jie Luo
- Department of Molecular Chemistry
and Materials Science, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Michael Montag
- Department of Molecular Chemistry
and Materials Science, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - David Milstein
- Department of Molecular Chemistry
and Materials Science, Weizmann Institute
of Science, Rehovot 7610001, Israel
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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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Liang Y, Efremenko I, Diskin-Posner Y, Avram L, Milstein D. Calcium-Ligand Cooperation Promoted Activation of N 2O, Amine, and H 2 as well as Catalytic Hydrogenation of Imines, Quinoline, and Alkenes. Angew Chem Int Ed Engl 2024; 63:e202401702. [PMID: 38533687 DOI: 10.1002/anie.202401702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/20/2024] [Accepted: 03/22/2024] [Indexed: 03/28/2024]
Abstract
Bond activation and catalysis using s-block metals are of great significance. Herein, a series of calcium pincer complexes with deprotonated side arms have been prepared using pyridine-based PNP and PNN ligands. The complexes were characterized by NMR and X-ray crystal diffraction. Utilizing the obtained calcium complexes, unprecedented N2O activation by metal-ligand cooperation (MLC) involving dearomatization-aromatization of the pyridine ligand was achieved, generating aromatized calcium diazotate complexes as products. Additionally, the dearomatized calcium complexes were able to activate the N-H bond as well as reversibly activate H2, offering an opportunity for the catalytic hydrogenation of various unsaturated molecules. DFT calculations were applied to analyze the electronic structures of the synthesized complexes and explore possible reaction mechanisms. This study is an important complement to the area of MLC and main-group metal chemistry.
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Affiliation(s)
- Yaoyu Liang
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Irena Efremenko
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Yael Diskin-Posner
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Liat Avram
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - David Milstein
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
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4
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Saha R, Panda S, Nanda A, Bagh B. Nickel-Catalyzed α-Alkylation of Arylacetonitriles with Challenging Secondary Alcohols. J Org Chem 2024; 89:6664-6676. [PMID: 36595479 DOI: 10.1021/acs.joc.2c02026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Nickel(II) complex 1 was utilized as a sustainable catalyst for α-alkylation of arylacetonitriles with challenging secondary alcohols. Arylacetonitriles with a wide range of functional groups were tolerated, and various cyclic and acyclic secondary alcohols were utilized to yield a large number of α-alkylated products. The plausible mechanism involves the base-promoted activation of precatalyst 1 to an active catalyst 2 (dehydrochlorinated product) which activates the O-H and C-H bonds of the secondary alcohol in a dehydrogenative pathway.
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Affiliation(s)
- Ratnakar Saha
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute, Bhimpur-Padanpur, Via Jatni, District Khurda, Bhubaneswar, Odisha 752050, India
| | - Surajit Panda
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute, Bhimpur-Padanpur, Via Jatni, District Khurda, Bhubaneswar, Odisha 752050, India
| | - Amareshwar Nanda
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute, Bhimpur-Padanpur, Via Jatni, District Khurda, Bhubaneswar, Odisha 752050, India
| | - Bidraha Bagh
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute, Bhimpur-Padanpur, Via Jatni, District Khurda, Bhubaneswar, Odisha 752050, India
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5
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Wu K, Lam N, Strassfeld DA, Fan Z, Qiao JX, Liu T, Stamos D, Yu JQ. Palladium (II)-Catalyzed C-H Activation with Bifunctional Ligands: From Curiosity to Industrialization. Angew Chem Int Ed Engl 2024; 63:e202400509. [PMID: 38419352 PMCID: PMC11216193 DOI: 10.1002/anie.202400509] [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: 01/08/2024] [Revised: 02/23/2024] [Accepted: 02/26/2024] [Indexed: 03/02/2024]
Abstract
In 2001, our curiosity to understand the stereochemistry of C-H metalation with Pd prompted our first studies in Pd(II)-catalyzed asymmetric C-H activation (RSC Research appointment: 020 7451 2545, Grant: RG 36873, Dec. 2002). We identified four central challenges: 1. poor reactivity of simple Pd salts with native substrates; 2. few strategies to control site selectivity for remote C-H bonds; 3. the lack of chiral catalysts to achieve enantioselectivity via asymmetric C-H metalation, and 4. low practicality due to limited coupling partner scope and the use of specialized oxidants. These challenges necessitated new strategies in catalyst and reaction development. For reactivity, we developed approaches to enhance substrate-catalyst affinity together with novel bifunctional ligands which participate in and accelerate the C-H cleavage step. For site-selectivity, we introduced the concept of systematically modulating the distance and geometry between a directing template, catalyst, and substrate to selectively access remote C-H bonds. For enantioselectivity, we devised predictable stereomodels for catalyst-controlled enantioselective C-H activation based on the participation of bifunctional ligands. Finally, for practicality, we have developed varied catalytic manifolds for Pd(II) to accommodate diverse coupling partners while employing practical oxidants such as simple peroxides. These advances have culminated in numerous C-H activation reactions, setting the stage for broad industrial applications.
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Affiliation(s)
- Kevin Wu
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Nelson Lam
- Department of Chemistry, Cambridge University, Cambridge, CB2 1EW, UK
| | - Daniel A Strassfeld
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Zhoulong Fan
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Jennifer X Qiao
- Small Molecule Drug Discovery, Bristol-Myers Squibb Research and Development, 250 Water Street, Cambridge, MA 02141, USA
| | - Tao Liu
- Discovery Chemistry Research & Technology Eli Lilly and Company, Lilly Biotechnology Center, 10290 Campus Point Dr, San Diego, CA 92121, USA
| | - Dean Stamos
- Research & Development, Flagship Pioneering, 55 Cambridge Parkway Suite 800E, Cambridge, MA 02142, USA
| | - Jin-Quan Yu
- Department of Chemistry, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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6
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Tian H, Ding CY, Liao RZ, Li M, Tang C. Cobalt-Catalyzed Acceptorless Dehydrogenation of Primary Amines to Nitriles. J Am Chem Soc 2024; 146:11801-11810. [PMID: 38626455 DOI: 10.1021/jacs.4c00493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2024]
Abstract
The direct double dehydrogenation from primary amines to nitriles without an oxidant or hydrogen acceptor is both intriguing and challenging. In this paper, we describe a non-noble metal catalyst capable of realizing such a transformation with high efficiency. A cobalt-centered N,N-bidentate complex was designed and employed as a metal-ligand cooperative dehydrogenation catalyst. Detailed kinetic studies, control experiments, and DFT calculations revealed the crucial hydride transfer, proton transfer, and hydrogen evolution processes. Finally, a tandem outer-sphere/inner-sphere mechanism was proposed for the dehydrogenation of amines to nitriles through an imine intermediate.
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Affiliation(s)
- Haitao Tian
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, China
| | - Cai-Yun Ding
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, China
| | - Rong-Zhen Liao
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, China
| | - Man Li
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, China
| | - Conghui Tang
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, China
- State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, China
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7
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Srivastava N, Singh AK. Protic- or anionic-NHCs with a classical-NHC in a single [Ru(CNC)(PPh 3) 2Cl]Cl pincer complex: direct comparison of structure & electronic properties and heterolytic H 2 splitting. Dalton Trans 2024; 53:6870-6874. [PMID: 38597195 DOI: 10.1039/d4dt00623b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Herein, we report the first set of pincer complexes 1 and 2 with the general formula [Ru(CNC)(PPh3)2Cl]Cl having a protic- and classical-NHC in the same molecule and nearly identical environments. Deprotonation of the protic-NHC complex 2 with one equivalent of base leads to the formation of anionic-NHC complex 2'. These complexes allow a direct comparison of protic- and anionic-NHCs with the classical-NHC ligand. A comparison of the molecular structure indicated that the metal carbene bond length trend is anionic-NHC > protic-NHC > classical-NHC. The electrochemical investigation revealed the electron donation tendency is classical-NHC > protic-NHC and anionic-NHC > protic-NHC. Cooperation between the metal and the ligand is indicated by the reaction of 2' with H2 gas at 1 atm pressure and 110 °C to give the Ru-hydride complex 3.
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Affiliation(s)
- Navdeep Srivastava
- Department of Chemistry, Indian Institute of Technology-Indore, Simrol, Khandwa Road, 433552, India.
| | - Amrendra K Singh
- Department of Chemistry, Indian Institute of Technology-Indore, Simrol, Khandwa Road, 433552, India.
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8
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Parsons LW, Berben LA. Expanding the Scope of Aluminum Chemistry with Noninnocent Ligands. Acc Chem Res 2024; 57:1087-1097. [PMID: 38581655 PMCID: PMC11025028 DOI: 10.1021/acs.accounts.3c00714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 03/21/2024] [Accepted: 03/25/2024] [Indexed: 04/08/2024]
Abstract
ConspectusAluminum is the most abundant metal in the earth's crust at 8%, and it is also widely available domestically in many countries worldwide, which ensures a stable supply chain. To further the applications of aluminum (Al), such as in catalysis and electronic and energy storage materials, there has been significant interest in the synthesis and characterization of new Al coordination compounds that can support electron transfer (ET) and proton transfer (PT) chemistry. This has been achieved using redox and chemically noninnocent ligands (NILs) combined with the highly stable M(III) oxidation state of Al and in some cases the heavier group 13 ions, Ga and In.When ligands participate in redox chemistry or facilitate the breaking or making of new bonds, they are often termed redox or chemically noninnocent, respectively. Al(III) in particular supports rich ligand-based redox chemistry because it is so redox inert and will support the ligand across many charge and protonation states without entering into the reaction chemistry. To a lesser extent, we have reported on the heavier group 13 elements Ga and In, and this chemistry will also be included in this Account, where available.This Account is arranged into two technical sections, which are (1) Structures of Al-NIL complexes and (2) Reactivity of Al-NIL complexes. Highlights of the research work include reversible redox chemistry that has been enabled by ligand design to shut down radical coupling pathways and to prevent loss of H2 from unsaturated ligand sites. These reversible redox properties have in turn enabled the characterization of Class III electron delocalization through Al when two NIL are bound to the Al(III) in different charge states. Characterization of the metalloaromatic character of square planar Al and Ga complexes has been achieved, and characterization of the delocalized electronic structures has provided a model within which to understand and predict the ET and PT chemistry of the NIL group 13 compounds. The capacity of Al-NIL complexes to perform ET and PT has been employed in reactions that use ET or PT reactivity only or in reactions where coupled ET/PT affords hydride transfer chemistry. As an example, ligand-based PT reactions initiate metal-ligand cooperative bond activation pathways for catalysis: this includes acceptorless dehydrogenation of formic acid and anilines and transfer hydrogenation chemistry. In a complementary approach, ligand based ET/PT chemistry has been used in the study of dihydropyridinate (DHP-) chemistry where it was shown that N-coordination of group 13 ions lowers kinetic barriers to DHP- formation. Taken together, the discussion presented herein illustrates that the NIL chemistry of Al(III), and also of Ga(III) and In(III) holds promise for further developments in catalysis and energy storage.
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Affiliation(s)
- Leo W.
T. Parsons
- Department of Chemistry, University of California, Davis, California 95616, United States
| | - Louise A. Berben
- Department of Chemistry, University of California, Davis, California 95616, United States
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9
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Ramspoth TF, Kootstra J, Harutyunyan SR. Unlocking the potential of metal ligand cooperation for enantioselective transformations. Chem Soc Rev 2024; 53:3216-3223. [PMID: 38381077 PMCID: PMC10985679 DOI: 10.1039/d3cs00998j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Indexed: 02/22/2024]
Abstract
Metal-ligand cooperation, in which both the metal and the ligand of a transition metal complex actively participate in chemical transformations leading to enhanced reactivity or selectivity in chemical reactions, has emerged as a powerful and versatile concept in catalysis. This Viewpoint discusses the development trajectory of transition metal-based complexes as catalysts in (de)hydrogenative processes, in particular those cases where metal-ligand cooperation has been invoked to rationalise the observed high reactivities and excellent selectivities. The historical context, mechanistic aspects and current applications are discussed with the suggestion to explore the potential of the MLC mode of action of such catalysts in enantioselective transformations beyond (de)hydrogenative processes.
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Affiliation(s)
- Tizian-Frank Ramspoth
- Institute for Chemistry, University of Groningen Institution Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
| | - Johanan Kootstra
- Institute for Chemistry, University of Groningen Institution Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
| | - Syuzanna R Harutyunyan
- Institute for Chemistry, University of Groningen Institution Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
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10
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Khatal SB, Purkayastha SK, Guha AK, Tothadi S, Pratihar S. Enhancing Precatalyst Performance and Robustness through Aromaticity: Insights from Iridaheteroaromatics. J Org Chem 2024; 89:2480-2493. [PMID: 38308648 DOI: 10.1021/acs.joc.3c02504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2024]
Abstract
Despite the inherent stability-enhancing benefits of dπ-pπ conjugation-induced aromaticity, metallaaromatic catalysts remain underutilized in this context, despite their reactivity with organic functionalities in stoichiometric reactions. We present a strategy for synthesizing a diverse range of iridaheteroaromatics, (L^L)IrIII(Cp*)I, including iridapyridylidene-indole, iridapyridene-indole, and iridaimidazole, via in situ deprotonation/metalation reactions utilizing [Cp*IrCl2]2 and the respective ligands. These catalysts exhibit enhanced σ-donor and π-acceptor properties, intrinsic σ-π continuum attributes, and versatile binding sites, contributing to stability through enhanced dπ-pπ conjugation-induced aromaticity. Spectroscopic data, X-ray crystallographic data, and density functional theory calculations confirm their aromaticity. These iridaheteroaromatics exhibit formidable catalytic ability across a spectrum of transformations under industrially viable conditions, notably excelling in highly selective cross alkylation and β-alkylation of alcohols and an eco-friendly avenue for quinolone synthesis, achieving remarkably high turnover frequencies (TOFs). Additionally, this method extends to the self-condensation of bioalcohols like ethanol, n-butanol, and n-hexanol in water, replicating conditions frequently encountered in primary fermentation solutions. These iridaheteroaromatics exhibit strong catalytic activity with fast reaction rates, high TOFs, broad substrate compatibility, and remarkable selectivity, displaying their potential as robust catalysts in large-scale applications and emphasizing their practical significance beyond their structural and theoretical importance.
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Affiliation(s)
- Sandip Bapu Khatal
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
- Inorganic Materials and Catalysis Division, CSIR-Central Salt & Marine Chemicals Research Institute, G. B. Marg, Bhavnagar 364002, Gujarat, India
| | | | - Ankur K Guha
- Advanced Computational Chemistry Centre, Cotton University, Panbazar, Guwahati, Assam 781001, India
| | - Srinu Tothadi
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
- Analytical and Environmental Sciences Division and Centralized Instrumentation Facility, CSIR-Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar 364002, India
| | - Sanjay Pratihar
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
- Inorganic Materials and Catalysis Division, CSIR-Central Salt & Marine Chemicals Research Institute, G. B. Marg, Bhavnagar 364002, Gujarat, India
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11
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Thiyagarajan S, Diskin-Posner Y, Montag M, Milstein D. Manganese-catalyzed base-free addition of saturated nitriles to unsaturated nitriles by template catalysis. Chem Sci 2024; 15:2571-2577. [PMID: 38362414 PMCID: PMC10866344 DOI: 10.1039/d3sc04935c] [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: 09/19/2023] [Accepted: 01/08/2024] [Indexed: 02/17/2024] Open
Abstract
The coupling of mononitriles into dinitriles is a desirable strategy, given the prevalence of nitrile compounds and the synthetic and industrial utility of dinitriles. Herein, we present an atom-economical approach for the heteroaddition of saturated nitriles to α,β- and β,γ-unsaturated mononitriles to generate glutaronitrile derivatives using a catalyst based on earth-abundant manganese. A broad range of such saturated and unsaturated nitriles were found to undergo facile heteroaddition with excellent functional group tolerance, in a reaction that proceeds under mild and base-free conditions using low catalyst loading. Mechanistic studies showed that this unique transformation takes place through a template-type pathway involving an enamido complex intermediate, which is generated by addition of a saturated nitrile to the catalyst, and acts as a nucleophile for Michael addition to unsaturated nitriles. This work represents a new application of template catalysis for C-C bond formation.
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Affiliation(s)
- Subramanian Thiyagarajan
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science Rehovot 7610001 Israel
| | - Yael Diskin-Posner
- Department of Chemical Research Support, Weizmann Institute of Science Rehovot 7610001 Israel
| | - Michael Montag
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science Rehovot 7610001 Israel
| | - David Milstein
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science Rehovot 7610001 Israel
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12
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Jalwal S, Regina A, Atreya V, Paranjothy M, Chakraborty S. NNN manganese complex-catalyzed α-alkylation of methyl ketones using alcohols: an experimental and computational study. Dalton Trans 2024. [PMID: 38251673 DOI: 10.1039/d3dt04321e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2024]
Abstract
We present here a phosphine-free, quinoline-based pincer Mn catalyst for α-alkylation of methyl ketones using primary alcohols as alkyl surrogates. The C-C bond formation reaction proceeds via a hydrogen auto-transfer methodology. The sole by-product formed is water, rendering the protocol atom efficient. Electronic structure theory studies corroborated the proposed mechanism.
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Affiliation(s)
- Sachin Jalwal
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342030, Rajasthan, India.
| | - Anitta Regina
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342030, Rajasthan, India.
| | - Vaishnavi Atreya
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342030, Rajasthan, India.
| | - Manikandan Paranjothy
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342030, Rajasthan, India.
| | - Subrata Chakraborty
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342030, Rajasthan, India.
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13
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Jena S, Frenzen L, Chugh V, Wu J, Weyhermüller T, Auer AA, Werlé C. A Cooperative Cobalt-Driven System for One-Carbon Extension in the Synthesis of ( Z)-Silyl Enol Ethers from Aldehydes: Unlocking Regio- and Stereoselectivity. J Am Chem Soc 2023; 145:27922-27932. [PMID: 38086018 PMCID: PMC10755702 DOI: 10.1021/jacs.3c10491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/30/2023] [Accepted: 12/01/2023] [Indexed: 12/28/2023]
Abstract
The research presented herein explores a cobalt-based catalytic system, distinctively featuring a cooperative boron-centric element within its intricate ligand architecture. This system is strategically engineered to enable the integration of a singular carbon atom into aldehydes, a process culminating in the production of (Z)-silyl enol ethers. Beyond offering an efficient one-pot synthesis route, this method adeptly overcomes challenges inherent to conventional techniques, such as the need for large amounts of additives, restrictive functional group tolerance, and extreme reaction temperatures. Initial mechanistic studies suggest the potential role of a cobalt-carbene complex as a catalytically significant species and underscore the importance of the borane segment. Collectively, these observations highlight the potential of this system in advancing complex bond activation pursuits.
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Affiliation(s)
- Soumyashree Jena
- Max
Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
- Ruhr
University Bochum, Universitätsstr.
150, 44801 Bochum, Germany
| | - Lars Frenzen
- Max
Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
| | - Vishal Chugh
- Max
Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
- Ruhr
University Bochum, Universitätsstr.
150, 44801 Bochum, Germany
| | - Jiajun Wu
- Max
Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
| | - Thomas Weyhermüller
- Max
Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
| | - Alexander A. Auer
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Christophe Werlé
- Max
Planck Institute for Chemical Energy Conversion, Stiftstr. 34−36, 45470 Mülheim an der Ruhr, Germany
- Ruhr
University Bochum, Universitätsstr.
150, 44801 Bochum, Germany
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14
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Moon HW, Wang F, Bhattacharyya K, Planas O, Leutzsch M, Nöthling N, Auer AA, Cornella J. Mechanistic Studies on the Bismuth-Catalyzed Transfer Hydrogenation of Azoarenes. Angew Chem Int Ed Engl 2023; 62:e202313578. [PMID: 37769154 DOI: 10.1002/anie.202313578] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 09/28/2023] [Accepted: 09/28/2023] [Indexed: 09/30/2023]
Abstract
Organobismuth-catalyzed transfer hydrogenation has recently been disclosed as an example of low-valent Bi redox catalysis. However, its mechanistic details have remained speculative. Herein, we report experimental and computational studies that provide mechanistic insights into a Bi-catalyzed transfer hydrogenation of azoarenes using p-trifluoromethylphenol (4) and pinacolborane (5) as hydrogen sources. A kinetic analysis elucidated the rate orders in all components in the catalytic reaction and determined that 1 a (2,6-bis[N-(tert-butyl)iminomethyl]phenylbismuth) is the resting state. In the transfer hydrogenation of azobenzene using 1 a and 4, an equilibrium between 1 a and 1 a ⋅ [OAr]2 (Ar=p-CF3 -C6 H4 ) is observed, and its thermodynamic parameters are established through variable-temperature NMR studies. Additionally, pKa -gated reactivity is observed, validating the proton-coupled nature of the transformation. The ensuing 1 a ⋅ [OAr]2 is crystallographically characterized, and shown to be rapidly reduced to 1 a in the presence of 5. DFT calculations indicate a rate-limiting transition state in which the initial N-H bond is formed via concerted proton transfer upon nucleophilic addition of 1 a to a hydrogen-bonded adduct of azobenzene and 4. These studies guided the discovery of a second-generation Bi catalyst, the rate-limiting transition state of which is lower in energy, leading to catalytic transfer hydrogenation at lower catalyst loadings and at cryogenic temperature.
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Affiliation(s)
- Hye Won Moon
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Feng Wang
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Kalishankar Bhattacharyya
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Oriol Planas
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Markus Leutzsch
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Nils Nöthling
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Alexander A Auer
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Josep Cornella
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
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15
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Singh T, Atreya V, Jalwal S, Anand A, Chakraborty S. Advances in Group VI Metal-Catalyzed Homogeneous Hydrogenation and Dehydrogenation Reactions. Chem Asian J 2023; 18:e202300758. [PMID: 37815164 DOI: 10.1002/asia.202300758] [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: 08/29/2023] [Revised: 10/10/2023] [Accepted: 10/10/2023] [Indexed: 10/11/2023]
Abstract
Transition metal-catalyzed homogeneous hydrogenation and dehydrogenation reactions for attaining plethora of organic scaffolds have evolved as a key domain of research in academia and industry. These protocols are atom-economic, greener, in line with the goal of sustainability, eventually pave the way for numerous novel environmentally benign methodologies. Appealing progress has been achieved in the realm of homogeneous catalysis utilizing noble metals. Owing to their high cost, less abundance along with toxicity issues led the scientific community to search for sustainable alternatives. In this context, earth- abundant base metals have gained substantial attention culminating enormous progress in recent years, predominantly with pincer-type complexes of nickel, cobalt, iron, and manganese. In this regard, group VI chromium, molybdenum and tungsten complexes have been overlooked and remain underdeveloped despite their earth-abundance and bio-compatibility. This review delineates a comprehensive overview in the arena of homogeneously catalysed (de)hydrogenation reactions using group VI base metals chromium, molybdenum, and tungsten till date. Various reactions have been described; hydrogenation, transfer hydrogenation, dehydrogenation, acceptorless dehydrogenative coupling, hydrogen auto transfer, along with their scope and brief mechanistic insights.
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Affiliation(s)
- Tushar Singh
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342037, Rajasthan
| | - Vaishnavi Atreya
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342037, Rajasthan
| | - Sachin Jalwal
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342037, Rajasthan
| | - Aman Anand
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342037, Rajasthan
| | - Subrata Chakraborty
- Department of Chemistry, Indian Institute of Technology Jodhpur, Karwar, Jodhpur, 342037, Rajasthan
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16
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Singh A, Kemper G, Weyhermüller T, Kaeffer N, Leitner W. Activated Mn-MACHO Complexes Form Stable CO 2 Adducts. Chemistry 2023:e202303438. [PMID: 38032321 DOI: 10.1002/chem.202303438] [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: 10/18/2023] [Revised: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 12/01/2023]
Abstract
Manganese(I) carbonyl complexes bearing a MACHO-type ligand (HN(CH2 CH2 PR2 )2 ) readily react in their amido form with CO2 to generate 4-membered {Mn-N-C-O} metallacycles. The stability of the adducts decreases with the steric demand of the R groups at phosphorous (R=isopropyl>adamantyl). The CO2 -adducts display generally a lower reactivity as compared to the parent amido complexes. These adducts can thus be interpretated as masked forms of the active amido catalysts and potentially play important roles as off-loop species or branching points in catalytic transformations of carbon dioxide.
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Affiliation(s)
- Ajeet Singh
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Gregor Kemper
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Thomas Weyhermüller
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Nicolas Kaeffer
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Walter Leitner
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Worringerweg 2, 52074, Aachen, Germany
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17
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Singh V, Jain H, Nath S, Adhikari D. Multielectron Redox Afforded by a Pincer Ligand Promoting Kumada Cross-Coupling Reactions. Chemistry 2023:e202303189. [PMID: 37988192 DOI: 10.1002/chem.202303189] [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: 09/29/2023] [Revised: 11/21/2023] [Accepted: 11/21/2023] [Indexed: 11/23/2023]
Abstract
The redox-active nature of a pincer has been exploited to conduct C-C cross-coupling reactions under mild conditions. A nickel complex with a NNN pincer was dimeric in the solid state, and the structure displayed a Ni2 N2 diamond core. In the dimeric structure, both ligand backbones house an electron, in the iminosemiquinonate form, to keep the metal's oxidation state at +2. In the presence of an aryl Grignard reagent, only 3 mol % loading the nickel complex generates a Kumada cross-coupled product in good yield from a wide variety of aryl-X (X= I, Br, Cl) substrates. That the ligand-based radical remains responsible for promoting such a coupling reaction following a radical pathway is suggested by TEMPO quenching. Furthermore, a radical-clock experiment along with tracing product distribution unambiguously supported the radical's involvement through the catalytic cycle. A series of thorough mechanistic probation, including computational DFT analysis, disclosed the cooperative action of both redox-active pincer ligand and the metal centre to drive the reaction.
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Affiliation(s)
- Vikramjeet Singh
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, SAS Nagar, 140306, India
| | - Harshit Jain
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, SAS Nagar, 140306, India
| | - Shounak Nath
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, United States
| | - Debashis Adhikari
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, SAS Nagar, 140306, India
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18
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Luo J, Lu L, Montag M, Liang Y, Milstein D. Hydrogenative alkene perdeuteration aided by a transient cooperative ligand. Nat Chem 2023; 15:1384-1390. [PMID: 37667011 DOI: 10.1038/s41557-023-01313-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 08/03/2023] [Indexed: 09/06/2023]
Abstract
Deuterogenation of unsaturated organic compounds is an attractive route for installing C(sp3)-D bonds, but the existing methods typically use expensive D2 and introduce only two deuterium atoms per unsaturation. Herein we report the hydrogenative perdeuteration of alkenes using readily available H2 and D2O instead of D2, catalysed by an acridanide-based ruthenium pincer complex and resulting in the incorporation of up to 4.9 D atoms per C=C double bond in a single synthetic step. Importantly, adding a catalytic amount of thiol, which serves as a transient cooperative ligand, ensures the incorporation of deuterium rather than protium by balancing the rates of two sequential deuteration processes. The current method opens an avenue for installing perdeuteroalkyl groups at specific sites from widely available alkenes under mild conditions.
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Affiliation(s)
- Jie Luo
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, Israel
| | - Lijun Lu
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, Israel
| | - Michael Montag
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, Israel
| | - Yaoyu Liang
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, Israel
| | - David Milstein
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, Israel.
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19
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Beard S, Grasa A, Viguri F, Rodríguez R, López JA, Lahoz FJ, García-Orduña P, Lamata P, Carmona D. Molecular hydrogen and water activation by transition metal frustrated Lewis pairs containing ruthenium or osmium components: catalytic hydrogenation assays. Dalton Trans 2023; 52:13216-13228. [PMID: 37665066 DOI: 10.1039/d3dt02339g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
The transition metal frustrated Lewis pair compounds [(Cym)M(κ3S,P,N-HL1)][SbF6] (Cym = η6-p-MeC6H4iPr; H2L1 = N-(p-tolyl)-N'-(2-diphenylphosphanoethyl)thiourea; M = Ru (5), Os (6)) have been prepared from the corresponding dimer [{(Cym)MCl}2(μ-Cl)2] and H2L1 by successive chloride abstraction with NaSbF6 and AgSbF6 and NH deprotonation with NaHCO3. Complexes 5 and 6 and the previously reported phosphano-guanidino compounds [(Cym)M(κ3P,N,N'-HL2)][SbF6] [H2L2 = N,N'-bis(p-tolyl)-N''-(2-diphenylphosphanoethyl) guanidine; M = Ru (7), Os (8)] and pyridinyl-guanidino compounds [(Cym)M(κ3N,N',N''-HL3)][SbF6] [H2L3 = N,N'-bis(p-tolyl)-N''-(2-pyridinylmethyl) guanidine; M = Ru (9), Os (10)] heterolytically activate H2 in a reversible manner affording the hydrido complexes [(Cym)MH(H2L)][SbF6] (H2L = H2L1; M = Ru (11), Os (12); H2L = H2L2; M = Ru (13), Os (14); H2L = H2L3; M = Ru (15), Os (16)). DFT calculations carried out on the hydrogenation of complex 7 support an FLP mechanism for the process. Heating 9 and 10 in methanol yields the orthometalated complexes [(Cym)M(κ3N,N',C-H2L3-H)][SbF6] (M = Ru (17), Os (18)). The phosphano-guanidino complex 7 activates deuterated water in a reversible fashion, resulting in the gradual deuteration of the three cymene methyl protons through sequential C(sp3)-H bond activation. From DFT calculations, a metal-ligand cooperative reversible mechanism that involves the O-H bond activation and the formation of an intermediate methylene cyclohexenyl complex has been proposed. Complexes 5-10 catalyse the hydrogenation of the CC double bond of styrene and a range of acrylates, the CO bond of acetophenone and the CN bond of N-benzylideneaniline and quinoline. The CC double bond of methyl acrylate adds to catalyst 9, affording complex 19 in which a new ligand exhibiting a fac κ3N,N',C coordination mode has been incorporated.
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Affiliation(s)
- Sophie Beard
- Departamento de Catálisis y Procesos Catalíticos. Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Alejandro Grasa
- Departamento de Catálisis y Procesos Catalíticos. Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Fernando Viguri
- Departamento de Catálisis y Procesos Catalíticos. Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Ricardo Rodríguez
- Departamento de Catálisis y Procesos Catalíticos. Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - José A López
- Departamento de Catálisis y Procesos Catalíticos. Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Fernando J Lahoz
- Departamento de Catálisis y Procesos Catalíticos. Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Pilar García-Orduña
- Departamento de Catálisis y Procesos Catalíticos. Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Pilar Lamata
- Departamento de Catálisis y Procesos Catalíticos. Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Daniel Carmona
- Departamento de Catálisis y Procesos Catalíticos. Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
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20
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Nath S, Yadav E, Raghuvanshi A, Singh AK. Ru(II) Complexes with Protic- and Anionic-Naked-NHC Ligands for Cooperative Activation of Small Molecules. Chemistry 2023; 29:e202301971. [PMID: 37377294 DOI: 10.1002/chem.202301971] [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: 06/21/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 06/29/2023]
Abstract
A set of ruthenium(II)-protic-N-heterocyclic carbene complexes, [Ru(NNCH )(PPh3 )2 (X)]Cl (1, X=Cl and 2, X=H) and their deprotonated forms [Ru(NNC)(PPh3 )2 (X)] (1', X=Cl and 2', X=H), in which NNC is a new unsymmetrical pincer ligand, are reported. The four complexes are interconvertible by simple acid-base chemistry. The combined theoretical and spectroscopic investigations indicate charge segregation in anionic-NHC complexes (1' and 2') and can be described from a Lewis pair perspective. The chemical reactivity of deprotonated complex 1' shows cooperative small molecule activation. Complex 1' activates H-H bond of hydrogen, C(sp3 )-I bond of iodomethane, and C(sp)-H bond of phenylacetylene. The activation of CO2 using anionic NHC complex 1' at moderate temperature and ambient pressure and subsequent conversion to formate is also described. All the new compounds have been characterized using ESI-MS, 1 H, 13 C, and 31 P NMR spectroscopy. Molecular structures of 1, 2, and 2' have also been determined with single-crystal X-ray diffraction. The cooperative small molecule activation perspective broadens the scope of potential applications of anionic-NHC complexes in small molecule activation, including the conversion of carbon dioxide to formate, a much sought after reaction in the renewable energy and sustainable development domains.
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Affiliation(s)
- Shambhu Nath
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India
| | - Ekta Yadav
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India
| | - Abhinav Raghuvanshi
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India
| | - Amrendra K Singh
- Department of Chemistry, Indian Institute of Technology Indore, Simrol, Indore, 453552, India
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21
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Parsons LWT, Berben LA. Metallated dihydropyridinates: prospects in hydride transfer and (electro)catalysis. Chem Sci 2023; 14:8234-8248. [PMID: 37564402 PMCID: PMC10411630 DOI: 10.1039/d3sc02080k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 07/14/2023] [Indexed: 08/12/2023] Open
Abstract
Hydride transfer (HT) is a fundamental step in a wide range of reaction pathways, including those mediated by dihydropyridinates (DHP-s). Coordination of ions directly to the pyridine ring or functional groups stemming therefrom, provides a powerful approach for influencing the electronic structure and in turn HT chemistry. Much of the work in this area is inspired by the chemistry of bioinorganic systems including NADH. Coordination of metal ions to pyridines lowers the electron density in the pyridine ring and lowers the reduction potential: lower-energy reactions and enhanced selectivity are two outcomes from these modifications. Herein, we discuss approaches for the preparation of DHP-metal complexes and selected examples of their reactivity. We suggest further areas in which these metallated DHP-s could be developed and applied in synthesis and catalysis.
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Affiliation(s)
- Leo W T Parsons
- Department of Chemistry, University of California Davis CA 95616 USA
| | - Louise A Berben
- Department of Chemistry, University of California Davis CA 95616 USA
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22
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Austen BJH, Clapson ML, Drover MW. Reactions of nickel boranyl compounds with pnictogen-carbon triple bonds. RSC Adv 2023; 13:19158-19163. [PMID: 37362339 PMCID: PMC10288830 DOI: 10.1039/d3ra02797j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 06/14/2023] [Indexed: 06/28/2023] Open
Abstract
The catalytic conversion of unsaturated small molecules such as nitriles into reduced products is of interest for the production of fine chemicals. In this vein, metal-ligand cooperativity has been leveraged to promote such reactivity, often conferring stability to bound substrate - a balancing act that may offer activation at the cost of turnover efficiency. This report describes the reactivity of a [(diphosphine)Ni] compound with pnictogen carbon triple bonds (R-C[triple bond, length as m-dash]E; E = N, P), where the diphosphine contains two pendant borane groups. For E = N, cooperative nitrile coordination is observed to afford {Ni}2 complexes displaying B-N interactions, whereas for E = P, B-P interactions are absent. This work additionally outlines a structure-activity relationship that uses nitrile dihydroboration as a model reaction to unveil the effect of SCS stabilization, employing [(diphosphine)Ni] where the diphosphine contains 0, 1, or 2 pendant Lewis acid groups.
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Affiliation(s)
- Brady J H Austen
- Department of Chemistry and Biochemistry, The University of Windsor 401 Sunset Avenue Windsor ON N9B 3P4 Canada
| | - Marissa L Clapson
- Department of Chemistry and Biochemistry, The University of Windsor 401 Sunset Avenue Windsor ON N9B 3P4 Canada
| | - Marcus W Drover
- Department of Chemistry and Biochemistry, The University of Windsor 401 Sunset Avenue Windsor ON N9B 3P4 Canada
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23
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Lin J, Li Y, Ke Z. Feature Analysis in High-Dimensional Data: Structure-Activity Relationships of Lewis Acid-Transition-Metal Complex-Catalyzed H 2 Activation. J Phys Chem A 2023; 127:4375-4387. [PMID: 37183362 DOI: 10.1021/acs.jpca.2c08987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Lewis acid-transition metal (LA-TM) catalysts have been proven to have an advantage in catalyzing hydrogen activation. Herein, a high-dimensional structure-activity relationship study is performed for LA-TM-catalyzed hydrogen activation by density functional theory calculations. The DPB-Ni complex is taken as the representative catalyst, and the explored Lewis acid sites and transition-metal centers include B, Al, Ga and Ni, Pd, Pt, respectively. Totally, four general hydrogen activation mechanisms are systematically studied among the nine catalytic systems. The Ga-Ni system undergoes the lowest free energy of activation (11.0 kcal/mol), which is considered to be the optimal combination of the Lewis acid site and transition-metal center. Furthermore, more than 100 parameters are used to analyze the structure-activity relationship, including the physical structure, the bond order, the atom charge, and many other properties. Key parameters of important structures are dug out to show a high correlation with the activity of the LA-TM systems, including the M-H2 distance, the H-H bond length, the second-order perturbation stabilization energy of M-H2, the bond order of the LA-TM, and so on. The multivariable analysis indicates that the feature related to the basic elemental properties and the global feature codetermine the activity of the catalyst. In the LA-TM system, the combination of IpLA/IpTM (Ip, the first ionization energy, the feature related to basic elemental properties) and the chemical hardness (the global feature) can better explain the activity of the catalyst. The IpLA/IpTM reflects the difficulty of breaking the LA-TM bond, affecting the reaction site of activating hydrogen. The hardness reflects the stability and reactivity of LA-TM-RC complexes. The above two features with the addition of the LA-TM bond length (the local feature) can better reflect the activity of the LA-TM system-catalyzed H2 activation. The feature combinations and the method of multidimensional data analysis should be informative guidance for the rational design of efficient LA-TM catalysts for H2 activation.
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Affiliation(s)
- Jiaxin Lin
- School of Materials Science and Engineering, PCFM Lab, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Yinwu Li
- School of Materials Science and Engineering, PCFM Lab, Sun Yat-sen University, Guangzhou 510006, P. R. China
| | - Zhuofeng Ke
- School of Materials Science and Engineering, PCFM Lab, Sun Yat-sen University, Guangzhou 510006, P. R. China
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24
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Wang B, Rong C, Lei M, Liu S, De Proft F. Mechanistic Study and Conceptual Chemical Reactivity Analysis of Hydroboration of Carbon Dioxide Catalyzed by a Manganese(I)-PNP-Pincer Complex. Inorg Chem 2023; 62:7366-7375. [PMID: 37129648 DOI: 10.1021/acs.inorgchem.3c00553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Designing efficient and selective catalysts for carbon dioxide reduction is an intensive research area in the recent literature on homogeneous catalysis. In this work, we study the catalytic activity of a newly reported Mn(I)-PNP-pincer catalyst with an embedded aromatic ring. First, we systematically examine its capability to yield different products and highlight the importance of ligand aromaticity and steric effects on metal-ligand cooperativity. We then further conceptually probe its reactivity with descriptors from both conceptual density functional theory and an information-theoretic approach, thereby proposing a novel partitioning of the reaction coordinate into three relevant regions. Our results show that the reactivity in these different regions is governed by different properties such as steric effects, electrophilicity/nucleophilicity, or aromaticity. We anticipate that this methodology, with the analytical tools employed in this study, can be generalized and extended to other catalytic systems and find applications in designing better catalysts.
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Affiliation(s)
- Bin Wang
- Research Group of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081, Hunan, P. R. China
| | - Chunying Rong
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081, Hunan, P. R. China
| | - Ming Lei
- State Key Laboratory of Chemical Resource Engineering, Institute of Computational Chemistry, College of Chemistry, Beijing University of Chemical Technology, Beijing 100029, China
| | - Shubin Liu
- Research Computing Center, University of North Carolina, Chapel Hill, North Carolina 27599-3420, United States
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, United States
| | - Frank De Proft
- Research Group of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
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Liang Y, Luo J, Diskin-Posner Y, Milstein D. Designing New Magnesium Pincer Complexes for Catalytic Hydrogenation of Imines and N-Heteroarenes: H 2 and N-H Activation by Metal-Ligand Cooperation as Key Steps. J Am Chem Soc 2023; 145:9164-9175. [PMID: 37068165 PMCID: PMC10141328 DOI: 10.1021/jacs.3c01091] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
Utilization of main-group metals as alternatives to transition metals in homogeneous catalysis has become a hot research area in recent years. However, their application in catalytic hydrogenation is less common due to the difficulty in heterolytic cleavage of the H-H bond. Employing aromatization/de-aromatization metal-ligand cooperation (MLC) highly enhances the H2 activation process, offering an efficient approach for the hydrogenation of unsaturated molecules catalyzed by main-group metals. Herein, we report a series of new magnesium pincer complexes prepared using PNNH-type pincer ligands. The complexes were characterized by NMR and X-ray single-crystal diffraction. Reversible activation of H2 and N-H bonds by MLC employing these pincer complexes was developed. Using the new magnesium complexes, homogeneously catalyzed hydrogenation of aldimines and ketimines was achieved, affording secondary amines in excellent yields. Control experiments and DFT studies reveal that a pathway involving MLC is favorable for the hydrogenation reactions. Moreover, the efficient catalysis was extended to the selective hydrogenation of quinolines and other N-heteroarenes, presenting the first example of hydrogenation of N-heteroarenes homogeneously catalyzed by early main-group metal complexes. This study provides a new strategy for hydrogenation of C═N bonds catalyzed by magnesium compounds and enriches the research of main-group metal catalysis.
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Affiliation(s)
- Yaoyu Liang
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Jie Luo
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Yael Diskin-Posner
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - David Milstein
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
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Pal S, Das S, Chakraborty S, Khanra S, Paul ND. Zn(II)-Catalyzed Multicomponent Sustainable Synthesis of Pyridines in Air. J Org Chem 2023; 88:3650-3665. [PMID: 36854027 DOI: 10.1021/acs.joc.2c02867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Herein, we report a Zn(II)-catalyzed solvent-free sustainable synthesis of tri- and tetra-substituted pyridines using alcohols as the primary feedstock and NH4OAc as the nitrogen source. Using a well-defined air-stable Zn(II)-catalyst, 1a, featuring a redox-active tridentate azo-aromatic pincer, 2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline (La), a wide variety of unsymmetrical 2,4,6-substituted pyridines were prepared by three-component coupling of primary and secondary alcohols with NH4OAc. Catalyst 1a is equally compatible with the four-component coupling. Unsymmetrical 2,4,6-substituted pyridines were also prepared via a four-component coupling of a primary alcohol with two different secondary alcohols and NH4OAc. A series of tetra-substituted pyridines were prepared up to 67% yield by coupling primary and secondary alcohols with 1-phenylpropan-1-one or 1,2-diphenylethan-1-one and NH4OAc. The 1a-catalyzed reactions also proceeded efficiently upon replacing the secondary alcohols with the corresponding ketones, producing the desired tri- and tetra-substituted pyridines in higher yields in a shorter reaction time. A few control experiments were performed to unveil the mechanistic aspects, which indicates that the active participation of the aryl-azo ligand during catalysis enables the Zn(II)-complex to act as an efficient catalyst for the present multicomponent reactions. Aerial oxygen acts as an oxidant during the Zn(II)-catalyzed dehydrogenation of alcohols, producing H2O and H2O2 as byproducts.
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Affiliation(s)
- Subhasree Pal
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Siuli Das
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Subhajit Chakraborty
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Subhankar Khanra
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
| | - Nanda D Paul
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Botanic Garden, Howrah 711103, India
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Elsby MR, Baker RT. Through the Looking Glass: Using the Lens of [SNS]-Pincer Ligands to Examine First-Row Metal Bifunctional Catalysts. Acc Chem Res 2023; 56:798-809. [PMID: 36921212 DOI: 10.1021/acs.accounts.2c00798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
Abstract
ConspectusHomogeneous catalysis is at the forefront of global efforts to innovate the synthesis of fine chemicals and achieve carbon-neutrality in energy applications. For decades, the push toward sustainable catalysis has focused on the development of first-row transition metal catalysts to supplant widespread use of precious metals. Metal-ligand cooperativity is an effective strategy to yield high-performing first-row metal molecular catalysts. Despite remarkable progress, state of the art catalysts often employ phosphorus-based ligands which are air-sensitive, potentially toxic, and on occasion offset the cost-savings of the metal. Thus, the development of simple and economical ligands composed of biomimetic donors should be a key focus that cannot be overlooked in the pursuit of sustainable catalyst candidates. This is an Account of our group's efforts to develop first-row transition metal complexes which use [SNS]-pincer ligands for bifunctional catalysis. We have synthesized two potentially tridentate ligands, one bearing an amido and two thioether donors [(SMeNSMe), L1] and one which includes thiolate, imine, and thioether donors [(SNSMe), L2], and used them as platforms upon which to explore the reaction pathways of first-row metals. The [SNS] ligand, L1, leads to formation of high-spin paramagnetic metal complexes of the type M(L1)2 in which the 6-membered ring thioether donor is hemilabile (M = Mn, Fe, Co). This allows Mn(L1)2 to function as a carbonyl hydroboration catalyst that operates by a novel hydride-free, inner-sphere reaction pathway. Exploring the reactivity of L2 with Fe and Ni revealed unique coordination chemistry and a variety of mono-, di-, tri-, and tetranuclear complexes enabled by bridging thiolates. Further studies showed L2 undergoes selective Caryl-S bond cleavage upon coordination to a metal with electron-rich phosphine donors, yielding a new (CNS)2- pincer ligand. The analogous reaction with L1 afforded a new (CNSMe)- pincer ligand via both Caryl-S and benzylic C-H bond cleavage. In an attempt to prepare Fe(L2)2, we obtained instead an Fe(N2S3) complex in which imine C-C bond formation affords a potentially hexadentate redox-active ligand. The Fe(N2S3) complex is a selective catalyst for hydroboration of aldehydes and appears to operate through a complicated mechanism. In contrast, a mechanistic study of Mn(L2)(CO)3-photocatalyzed dihydroboration of nitriles indicated that both the flexibility of the κ3-SNSMe ligand (fac- vs mer-coordination) and ability of Mn to undergo a spin-state change are required to access low energy barriers for this transformation. To effectively compare the reactivity of the thiolate vs amido donor, we prepared two Cu complexes, Cu(L1)(IPr) and Cu(L2)(IPr) [IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene], showing that, while both served as carbonyl hydroboration catalysts, only the amido complex was an effective catalyst for carbonyl hydrosilylation. In addition, complexes of the type Zn(L1)2, Zn(L2)2, and Zn(L1)(L2), were also effective for catalytic carbonyl hydroboration. While Zn(L1)(L2) was most active, catalyst speciation studies showed that each undergoes bifunctional catalyst activation to form a Zn bis(alkoxide) catalyst. Overall, our observations using [SNS] ligands with first-row transition metals show how the absence of traditional phosphine donors leads to different fundamental reactivity. Furthermore, this Account demonstrates the gap of knowledge which exists in understanding the reactivity of sulfur-based ligands to promote more widespread adoption of sustainable ligands.
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Affiliation(s)
- Matthew R Elsby
- Department of Chemistry, Yale University, 225 Prospect St, New Haven, Connecticut 06520 United States
| | - R Tom Baker
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, 30 Marie Curie, University of Ottawa, Ottawa, ON K1N 6N5 Canada
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Nickel-catalyzed cooperative B-H bond activation for hydroboration of N‑heteroarenes, ketones and imines. CHINESE CHEM LETT 2023. [DOI: 10.1016/j.cclet.2023.108293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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Kanti Guha A. Inter-Alkali-Metal Dative Bond in the MMN 3 - (M=Alkali Metal) Cluster. Chemphyschem 2023; 24:e202200935. [PMID: 36717761 DOI: 10.1002/cphc.202200935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/24/2023] [Accepted: 01/30/2023] [Indexed: 02/01/2023]
Abstract
Alkali metals are generally Lewis acids. On the contrary, Lewis basic character of alkali metals forming donor - acceptor complexes is a very rare phenomenon. In this contribution, I have theoretically designed an anionic cluster MMN3 - (M=alkali metals) on the basis of experimentally known reagent, alkali salt of azide ion MN3 , which shows unprecedented M:- →M donor-acceptor interaction. To the best of author's knowledge, the characterization of such donor-acceptor interaction among alkali metals is unprecedented. Formation of the 2c-2e donor-acceptor bonds have been confirmed by quantum theory of atoms in molecules and electron localization function analyses. The calculated bond dissociation energies are significant suggesting their possible spectroscopic identification.
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Affiliation(s)
- Ankur Kanti Guha
- Advanced Computational Chemistry Centre, Cotton University, Panbazar, Guwahati, Assam, 781001, India
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Luo M, Chen D, Li Q, Xia H. Unique Properties and Emerging Applications of Carbolong Metallaaromatics. Acc Chem Res 2023; 56:924-937. [PMID: 36718118 DOI: 10.1021/acs.accounts.2c00750] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
ConspectusAromatic compounds are important in synthetic chemistry, biomedicines, and materials science. As a special type of aromatic complex, transition-metal-based metallaaromatics contain at least one transition metal in an aromatic framework. The chemistry of metallaaromatics has seen much progress in computational studies and synthetic methods, but their properties and applications are still emerging. In recent years, we have disclosed a series of metal-centered conjugated polycyclic metallacycles in which a carbon chain is chelated to a metal center through at least three metal-carbon bonds. These are termed carbolong complexes and exhibit good stability to water, oxygen, light, and heat on account of their polydentate chelation and aromaticity, making them easy to handle. Carbolong complexes are not only special π-conjugated aromatics but also organometallics; therefore, they have the properties of both species. In this Account, we showcase the recent advances in their applications based on their different properties.First, carbolong complexes are a special kind of π-conjugated aromatic, with the ability to transmit electrons, allowing them to function as single-molecule conductors and candidates for electron transporting layer materials (ETLs) in solar cells. A series of carbolong complexes have been proved to be useful as achievable ETLs which enhance device performance in both organic solar cells and perovskite solar cells.Second, due to the involvement of d orbitals in the conjugation, carbolong complexes normally exhibit strong and broad absorption, even in some cases extending to the near-infrared region (NIR). The absorbed optical energy can be converted into light, heat, and ultrasound; consequently, carbolong compounds can be used as core moieties in smart materials. For example, 7C carbolong complexes were found to exhibit aggregation-enhanced near-infrared emission (AIEE). Some 12C carbolong complexes have been designed into the core moieties of NIR-responsive polymers, such as cylindrical NIR-responsive materials, self-healing materials, and shape memory materials. In contrast to the stereotypically toxic osmium compounds such as the highly toxic OsO4, some osmium carbolong complexes exhibit low cell cytotoxicity and good biocompatibility; consequently, they also have potential applications in the biomedical area. For example, benefiting from broad absorption in the NIR, 9C and 12C carbolong complexes have been used in photoacoustic imaging and photothermal therapy, respectively. In addition, photodynamic therapeutic applications which take advantage of a carbolong peroxo complex are discussed.Third, as special transition-metal complexes chelated by carbon-based ligands, a carbolong peroxo complex has displayed catalytic activity in the dehydrogenation of alcohols and a bimetallic carbolong complex has been used to catalyze difunctionalization reactions of unactivated alkenes.Overall, aromatic carbolong complexes have been applied to photovoltaics, smart materials, phototherapy, and catalytic reactions. Moving forward, we hope that this Account will shed light on future studies and theoretical research and encourage more discoveries of the properties of other metallaaromatics.
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Affiliation(s)
- Ming Luo
- Shenzhen Grubbs Institute, Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Dafa Chen
- Shenzhen Grubbs Institute, Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Qian Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Haiping Xia
- Shenzhen Grubbs Institute, Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China.,State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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Sustainable amidation through acceptorless dehydrogenative coupling by pincer-type catalysts: recent advances. PURE APPL CHEM 2023. [DOI: 10.1515/pac-2022-1101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Abstract
The amide functional group is ubiquitous in living organisms, and is of particular importance in bioactive compounds and pharmaceuticals. Because of the prevalence and significance of the amide bond, considerable efforts have been invested throughout the years in developing new synthetic methodologies for its formation. Nevertheless, amide synthesis still largely relies on variants of the traditional condensation of carboxylic acids and amines, mediated by stoichiometric coupling reagents. This poses a sustainability challenge, since such reactions suffer from unfavorable atom and step economies, involve harmful chemicals and produce chemical waste. Hence, establishing sustainable approaches to amide synthesis is of great importance. Over the last two decades, we have developed homogeneous catalytic reactions for sustainable synthetic transformations, primarily based on transition metal complexes of pincer ligands. A considerable portion of these efforts has been devoted to acceptorless dehydrogenative coupling, including that of alcohols and amines through ruthenium-catalyzed reactions. These latter processes generate amides without resorting to coupling reagents and typically produce no waste, with their only byproduct being H2 gas, which is itself a valuable resource. In the present review, we chronicle our progress in this area of research since 2014. This includes the use of water and ammonia as amidation reagents, expanding the scope of amidation substrates and target amides, achieving milder reaction conditions, development of amidation-based liquid organic hydrogen carrier systems, and introduction of manganese-based catalysts.
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Auer M, Bolten J, Eichele K, Schubert H, Sindlinger CP, Wesemann L. Heavy metalla vinyl-cations show metal-Lewis acid cooperativity in reaction with small molecules (NH 3, N 2H 4, H 2O, H 2). Chem Sci 2023; 14:514-524. [PMID: 36741530 PMCID: PMC9847682 DOI: 10.1039/d2sc05620h] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 11/24/2022] [Indexed: 11/25/2022] Open
Abstract
Halide abstraction from tetrylidene complexes [TbbE(Br)IrH(PMe3)3] [E = Ge (1), Sn (2)] and [Ar*E(Cl)IrH(PMe3)3] gives the salts [TbbEIrH(PMe3)3][BArF 4] [E = Ge (3), Sn (4)] and [Ar*EIrH(PMe3)3][BArF 4] [E = Ge (3'), E = Sn (4')] (Tbb = 2,6-[CH(SiMe3)2]2-4-(t-Bu)C6H2, Ar* = 2,6-Trip2C6H3, Trip = 2,4,6-triisopropylphenyl). Bonding analysis suggests their most suitable description as metalla-tetrela vinyl cations with an Ir[double bond, length as m-dash]E double bond and a near linear coordination at the Ge/Sn atoms. Cationic complexes 3 and 4 oxidatively add NH3, N2H4, H2O, HCl, and H2 selectively to give: [TbbGe(NH2)IrH2(PMe3)3][BArF 4] (5), [TbbE(NHNH2)IrH2(PMe3)3][BArF 4] [E = Ge (7), Sn (8)], [TbbE(OH)IrH2(PMe3)3][BArF 4] [E = Ge (9), Sn (10)], [TbbE(Cl)IrH2(PMe3)3][BArF 4] [E = Ge (11a), Sn (12a)], [TbbGe(H)IrH2(PMe3)3][BArF 4] (13), [TbbSn(μ-H3)Ir(PMe3)3][BArF 4] (14), and [TbbSn(H)IrH2(PMe3)3][BArF 4] (15). 14 isomerizes to give 15via an 1,2-H shift reaction. Hydride addition to cation 3 gives a mixture of products [TbbGeHIrH(PMe3)3] (16) and [TbbGeIrH2(PMe3)3] (17) and a reversible 1,2-H shift between 16 and 17 was studied. In the tin case 4 the dihydride [TbbSnIrH2(PMe3)3] (18) was isolated exclusively. The PMe3 and PEt3 derivatives, 18 and [TbbSnIrH2(PEt3)3] (19), respectively, could also be synthesized in reaction of [TbbSnH2]- with the respective chloride [(R3P) n IrCl] (R = Me, n = 4; R = Et, n = 3). Reaction of complex 19 with CO gives the substitution product [TbbSnIrH2(CO)(PEt3)2] (20). Further reaction with CO results in hydrogen transfer from the iridium to the tin atom to give [TbbSnH2Ir(CO)2(PEt3)2] (21). The reversibility of this ligand induced reductive elimination transferring 20 to 21 is shown.
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Affiliation(s)
- Maximilian Auer
- Institut für Anorganische ChemieAuf der Morgenstelle 1872076 TübingenGermany
| | - Janina Bolten
- Institut für Anorganische ChemieAuf der Morgenstelle 1872076 TübingenGermany
| | - Klaus Eichele
- Institut für Anorganische ChemieAuf der Morgenstelle 1872076 TübingenGermany
| | - Hartmut Schubert
- Institut für Anorganische ChemieAuf der Morgenstelle 1872076 TübingenGermany
| | - Christian P. Sindlinger
- Institut für Anorganische Chemie, Universität StuttgartPfaffenwaldring 5570569 StuttgartGermany
| | - Lars Wesemann
- Institut für Anorganische ChemieAuf der Morgenstelle 1872076 TübingenGermany
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Papa V, Fessler J, Zaccaria F, Hervochon J, Dam P, Kubis C, Spannenberg A, Wei Z, Jiao H, Zuccaccia C, Macchioni A, Junge K, Beller M. Efficient Hydrogenation of N-Heterocycles Catalyzed by NNP-Manganese(I) Pincer Complexes at Ambient Temperature. Chemistry 2023; 29:e202202774. [PMID: 36193859 PMCID: PMC10100126 DOI: 10.1002/chem.202202774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Indexed: 11/06/2022]
Abstract
Manganese-catalyzed hydrogenation reactions have aroused widespread interest in recent years. Among the catalytic systems described, especially PNP- and NNP-Mn pincer catalysts have been reported for the hydrogenation of aldehydes, ketones, nitriles, aldimines and esters. Furthermore, NNP-Mn pincer compounds are efficient catalysts for the hydrogenolysis of less reactive amides, ureas, carbonates, and carbamates. Herein, the synthesis and application of specific imidazolylaminophosphine ligands and the corresponding Mn pincer complexes are described. These new catalysts have been characterized and studied by a combination of experimental and theoretical investigations, and their catalytic activities have been tested in several hydrogenation reactions with good to excellent performance. Especially, the reduction of N-heterocycles can be performed under very mild conditions.
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Affiliation(s)
- Veronica Papa
- Leibniz-Institut für Katalyse e. V.Albert-Einstein-Straße 29A18059RostockGermany
- Istituto italiano di tecnologiaVia Morego 3016163GenovaItaly
| | - Johannes Fessler
- Leibniz-Institut für Katalyse e. V.Albert-Einstein-Straße 29A18059RostockGermany
| | - Francesco Zaccaria
- Dipartimento di Chimica, Biologia e Biotecnologie and CIRCCUniversità degli Studi di Perugia06123PerugiaItaly
| | - Julien Hervochon
- Leibniz-Institut für Katalyse e. V.Albert-Einstein-Straße 29A18059RostockGermany
| | - Phong Dam
- Leibniz-Institut für Katalyse e. V.Albert-Einstein-Straße 29A18059RostockGermany
| | - Christoph Kubis
- Leibniz-Institut für Katalyse e. V.Albert-Einstein-Straße 29A18059RostockGermany
| | - Anke Spannenberg
- Leibniz-Institut für Katalyse e. V.Albert-Einstein-Straße 29A18059RostockGermany
| | - Zhihong Wei
- Leibniz-Institut für Katalyse e. V.Albert-Einstein-Straße 29A18059RostockGermany
- Institute of Molecular ScienceKey Laboratory of Materials for Energy Conversion and Storage of Shanxi ProvinceShanxi University030006TaiyuanP. R. China
| | - Haijun Jiao
- Leibniz-Institut für Katalyse e. V.Albert-Einstein-Straße 29A18059RostockGermany
| | - Cristiano Zuccaccia
- Dipartimento di Chimica, Biologia e Biotecnologie and CIRCCUniversità degli Studi di Perugia06123PerugiaItaly
| | - Alceo Macchioni
- Dipartimento di Chimica, Biologia e Biotecnologie and CIRCCUniversità degli Studi di Perugia06123PerugiaItaly
| | - Kathrin Junge
- Leibniz-Institut für Katalyse e. V.Albert-Einstein-Straße 29A18059RostockGermany
| | - Matthias Beller
- Leibniz-Institut für Katalyse e. V.Albert-Einstein-Straße 29A18059RostockGermany
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Antico E, Leutzsch M, Wessel N, Weyhermüller T, Werlé C, Leitner W. Selective oxidation of silanes into silanols with water using [MnBr(CO) 5] as a precatalyst. Chem Sci 2022; 14:54-60. [PMID: 36605749 PMCID: PMC9769106 DOI: 10.1039/d2sc05959b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 11/18/2022] [Indexed: 12/03/2022] Open
Abstract
The development of earth-abundant catalysts for the selective conversion of silanes to silanols with water as an oxidant generating valuable hydrogen as the only by-product continues to be a challenge. Here, we demonstrate that [MnBr(CO)5] is a highly active precatalyst for this reaction, operating under neutral conditions and avoiding the undesired formation of siloxanes. As a result, a broad substrate scope, including primary and secondary silanes, could be converted to the desired products. The turnover performances of the catalyst were also examined, yielding a maximum TOF of 4088 h-1. New light was shed on the debated mechanism of the interaction between [MnBr(CO)5] and Si-H bonds based on the reaction kinetics (including KIEs of PhMe2SiD and D2O) and spectroscopic techniques (FT-IR, GC-TCD, 1H-, 29Si-, and 13C-NMR). The initial activation of [MnBr(CO)5] was found to result from the formation of a manganese(i) hydride species and R3SiBr, and the experimental data are most consistent with a catalytic cycle comprising a cationic tricarbonyl Mn(i) unit as the active framework.
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Affiliation(s)
- Emanuele Antico
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645470 Mülheim an der RuhrGermany,Institut für Technische und Makromolekulare Chemie (ITMC), RWTH Aachen UniversityWorringer Weg 252074 AachenGermany
| | - Markus Leutzsch
- Max-Planck-Institut für KohlenforschungKaiser-Wilhelm-Platz 145470 Mülheim an der RuhrGermany
| | - Niklas Wessel
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645470 Mülheim an der RuhrGermany,Institut für Technische und Makromolekulare Chemie (ITMC), RWTH Aachen UniversityWorringer Weg 252074 AachenGermany
| | - Thomas Weyhermüller
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645470 Mülheim an der RuhrGermany
| | - Christophe Werlé
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645470 Mülheim an der RuhrGermany,Ruhr University BochumUniversitätsstr. 15044801 BochumGermany
| | - Walter Leitner
- Max Planck Institute for Chemical Energy ConversionStiftstr. 34–3645470 Mülheim an der RuhrGermany,Institut für Technische und Makromolekulare Chemie (ITMC), RWTH Aachen UniversityWorringer Weg 252074 AachenGermany
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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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36
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Do VK, Vargas NA, Chavez AJ, Zhang L, Cherepakhin V, Lu Z, Currier RP, Dub PA, Gordon JC, Williams TJ. Pressurized Formic Acid Dehydrogenation: An Entropic Spring Replaces Hydrogen Compression Cost. Catal Sci Technol 2022; 12:7182-7189. [PMID: 37192930 PMCID: PMC10168027 DOI: 10.1039/d2cy00676f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Formic acid is unique among liquid organic hydrogen carriers (LOHCs), because its dehydrogenation is highly entropically driven. This enables the evolution of high-pressure hydrogen at mild temperatures that is difficult to achieve with other LOHCs, conceptually by releasing the "spring" of energy stored entropically in the liquid carrier. Applications calling for hydrogen-on-demand, such as vehicle filling, require pressurized H2. Hydrogen compression dominates the cost for such applications, yet there are very few reports of selective, catalytic dehydrogenation of formic acid at elevated pressure. Herein, we show that homogenous catalysts with various ligand frameworks, including Noyori-type tridentate (PNP, SNS, SNP, SNPO), bidentate chelates (pyridyl)NHC, (pyridyl)phosphine, (pyridyl)sulfonamide, and their metallic precursors, are suitable catalysts for the dehydrogenation of neat formic acid under self-pressurizing conditions. Quite surprisingly, we discovered that their structural differences can be related to performance differences in their respective structural families, with some tolerant or intolerant of pressure and others that are significantly advantaged by pressurized conditions. We further find important roles for H2 and CO in catalyst activation and speciation. In fact, for certain systems, CO behaves as a healing reagent when trapped in a pressurizing reactor system, enabling extended life from systems that would be otherwise deactivated.
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Affiliation(s)
- Van K Do
- Loker Hydrocarbon Research Institute, Wrigley Institute for Environmental Studies, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089, United States
| | - Nicolas Alfonso Vargas
- Loker Hydrocarbon Research Institute, Wrigley Institute for Environmental Studies, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089, United States
| | - Anthony J Chavez
- Loker Hydrocarbon Research Institute, Wrigley Institute for Environmental Studies, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089, United States
| | - Long Zhang
- Loker Hydrocarbon Research Institute, Wrigley Institute for Environmental Studies, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089, United States
| | - Valeriy Cherepakhin
- Loker Hydrocarbon Research Institute, Wrigley Institute for Environmental Studies, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089, United States
| | - Zhiyao Lu
- Loker Hydrocarbon Research Institute, Wrigley Institute for Environmental Studies, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089, United States
| | - Robert P Currier
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Pavel A Dub
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - John C Gordon
- National Security Education Center (NSEC), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Travis J Williams
- Loker Hydrocarbon Research Institute, Wrigley Institute for Environmental Studies, and Department of Chemistry, University of Southern California, Los Angeles, California, 90089, United States
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37
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Redox-active ligands for chemical, electrochemical, and photochemical molecular conversions. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214804] [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]
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38
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Padilla R, Ni Z, Mihrin D, Wugt Larsen R, Nielsen M. Catalytic Base‐Free Transfer Hydrogenation of Biomass Derived Furanic Aldehydes with Bioalcohols and PNP Pincer Complexes. ChemCatChem 2022. [DOI: 10.1002/cctc.202200819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Affiliation(s)
- Rosa Padilla
- Department of Chemistry Technical University of Denmark Kemitorvet 207 Building 206 Denmark
| | - Zhenwei Ni
- Department of Chemistry Technical University of Denmark Kemitorvet 207 Building 206 Denmark
| | - Dmytro Mihrin
- Department of Chemistry Technical University of Denmark Kemitorvet 207 Building 206 Denmark
| | - René Wugt Larsen
- Department of Chemistry Technical University of Denmark Kemitorvet 207 Building 206 Denmark
| | - Martin Nielsen
- Department of Chemistry Technical University of Denmark Kemitorvet 207 Building 206 Denmark
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39
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Skaria M, Culpepper JD, Daly SR. Leveraging Metal and Ligand Reactive Sites for One Pot Reactions: Ligand-Centered Borenium Ions for Tandem Catalysis with Palladium. Chemistry 2022; 28:e202201791. [PMID: 35997655 PMCID: PMC9828003 DOI: 10.1002/chem.202201791] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Indexed: 01/12/2023]
Abstract
Tandem catalysts that perform two different organic transformations in a single pot are highly desirable because they enable rapid and efficient assembly of simple organic building blocks into more complex molecules. Many examples of tandem catalysis rely on metal-catalyzed reactions involving one or more metal complexes. Remarkably, despite surging interest in the development of chemically reactive (i. e., non-innocent) ligands, there are few examples of metal complexes that leverage ligand-centered reactivity to perform catalytic reactions in tandem with separate catalytic reactions at the metal. Here we report how multifunctional Pd complexes with triaminoborane-derived diphosphorus ligands, called TBDPhos, appear to facilitate borenium-catalyzed cycloaddition reactions at the ligand, and Pd-catalyzed Stille and Suzuki cross-coupling reactions at the metal. Both transformations can be accessed in one pot to afford rare examples of tandem catalysis using separate metal and ligand catalysis sites in a single complex.
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Affiliation(s)
- Manisha Skaria
- Department of ChemistryThe University of IowaIowa CityIowa52242USA
| | | | - Scott R. Daly
- Department of ChemistryThe University of IowaIowa CityIowa52242USA
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40
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Yaacoub L, Dutta I, Werghi B, Chen BWJ, Zhang J, Hamad EA, Ling Ang EP, Pump E, Sedjerari AB, Huang KW, Basset JM. Formic Acid Dehydrogenation via an Active Ruthenium Pincer Catalyst Immobilized on Tetra-Coordinated Aluminum Hydride Species Supported on Fibrous Silica Nanospheres. ACS Catal 2022. [DOI: 10.1021/acscatal.2c04137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Layal Yaacoub
- Division of Physical Science and Engineering and KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Indranil Dutta
- Division of Physical Science and Engineering and KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Baraa Werghi
- Division of Physical Science and Engineering and KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Benjamin W. J. Chen
- Agency for Science, Technology, and Research, Institute of High Performance Computing, 1 Fusionopolis Way, #16−16 Connexis, Singapore 138632, Singapore
| | - Jia Zhang
- Agency for Science, Technology, and Research, Institute of High Performance Computing, 1 Fusionopolis Way, #16−16 Connexis, Singapore 138632, Singapore
| | - Edy Abou Hamad
- Imaging and Characterization Department, KAUST Core Labs, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia
| | - Eleanor Pei Ling Ang
- Division of Physical Science and Engineering and KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Eva Pump
- Division of Physical Science and Engineering and KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Anissa Bendjeriou Sedjerari
- Division of Physical Science and Engineering and KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Kuo-Wei Huang
- Division of Physical Science and Engineering and KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
- Agency for Science, Technology, and Research, Institute of Materials Research and Engineering and Institute of Sustainability for Chemicals, Energy and Environment, Singapore 138634, Singapore
| | - Jean-Marie Basset
- Division of Physical Science and Engineering and KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
- Institut de Recherche de Chimie Paris, 11 Rue Pierre et Marie Curie, Cedex 05 75231, Paris
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41
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Liang Y, Das UK, Luo J, Diskin-Posner Y, Avram L, Milstein D. Magnesium Pincer Complexes and Their Applications in Catalytic Semihydrogenation of Alkynes and Hydrogenation of Alkenes: Evidence for Metal-Ligand Cooperation. J Am Chem Soc 2022; 144:19115-19126. [PMID: 36194894 PMCID: PMC9585592 DOI: 10.1021/jacs.2c08491] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The development of catalysts for environmentally benign organic transformations is a very active area of research. Most of the catalysts reported so far are based on transition-metal complexes. In recent years, examples of catalysis by main-group metal compounds have been reported. Herein, we report a series of magnesium pincer complexes, which were characterized by NMR and X-ray single-crystal diffraction. Reversible activation of H2 via aromatization/dearomatization metal-ligand cooperation was studied. Utilizing the obtained complexes, the unprecedented homogeneous main-group metal catalyzed semihydrogenation of alkynes and hydrogenation of alkenes were demonstrated under base-free conditions, affording Z-alkenes and alkanes as products, respectively, with excellent yields and selectivities. Control experiments and DFT studies reveal the involvement of metal-ligand cooperation in the hydrogenation reactions. This study not only provides a new approach for the semihydrogenation of alkynes and hydrogenation of alkenes catalyzed by magnesium but also offers opportunities for the hydrogenation of other compounds catalyzed by main-group metal complexes.
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Affiliation(s)
- Yaoyu Liang
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Uttam Kumar Das
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Jie Luo
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Yael Diskin-Posner
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Liat Avram
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - David Milstein
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
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42
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Metal free activation of water and ammonia by neutral tricoordinate pyramidal boron: a computational study. Struct Chem 2022. [DOI: 10.1007/s11224-022-02060-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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43
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Ribeiro Gouveia L, Ison EA. Well-Defined ENENES Re and Mn Complexes and Their Application in Catalysis: The Role of Potassium tert-Butoxide. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Liana Ribeiro Gouveia
- Department of Chemistry, North Carolina State University, 2620 Yarbrough Drive, Raleigh, North Carolina 27695-8204, United States
| | - Elon A. Ison
- Department of Chemistry, North Carolina State University, 2620 Yarbrough Drive, Raleigh, North Carolina 27695-8204, United States
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44
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Hollingsworth WM, Hill EA. Exploring the potential role of heavy pnictogen elements in ligand design for new metal-ligand cooperative chemistry. J COORD CHEM 2022. [DOI: 10.1080/00958972.2022.2124863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Affiliation(s)
- W. M. Hollingsworth
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL, USA
| | - E. A. Hill
- Department of Chemistry and Biochemistry, Auburn University, Auburn, AL, USA
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45
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Dinh HM, Gridneva T, Karimata A, Garcia-Roca A, Pruchyathamkorn J, Patil PH, Petrov A, Sarbajna A, Lapointe S, Khaskin E, Fayzullin RR, Khusnutdinova JR. Single and double deprotonation/dearomatization of the N,S-donor pyridinophane ligand in ruthenium complexes. Dalton Trans 2022; 51:14734-14746. [PMID: 36106442 DOI: 10.1039/d2dt02219b] [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
We report a series of ruthenium complexes with a tetradentate N,S-donor ligand, 2,11-dithia[3.3](2,6)pyridinophane (N2S2), that undergo single and double deprotonation in the presence of a base leading to the deprotonation of one or both pyridine rings. Both singly and doubly deprotonated complexes were structurally characterized by single-crystal X-ray diffraction. The NMR spectra are indicative of the dearomatization of one or both pyridine rings upon the deprotonation of the CH2-S arm, similar to the dearomatization of phosphine-containing pincer ligands. The deprotonated (N2S2)Ru complexes did not show appreciable catalytic or stoichiometric reactivity in transfer hydrogenation, hydrogenation and dehydrogenation of alcohols, and attempted activation of H2, CO2, and other substrates. Such a lack of reactivity is likely due to the low stability of the deprotonated species as evident from the structural characterization of one of the decomposition products in which shrinkage of the macrocyclic ring occurs via picolyl arm migration.
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Affiliation(s)
- Hoan Minh Dinh
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| | - Tatiana Gridneva
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| | - Ayumu Karimata
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| | - Alèria Garcia-Roca
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| | - Jiratheep Pruchyathamkorn
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| | - Pradnya H Patil
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| | - Andrey Petrov
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| | - Abir Sarbajna
- Okinawa Institute of Science and Technology Graduate University, Coordination Chemistry and Catalysis Unit, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
| | - 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, FRC 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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46
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Chugh V, Chatterjee B, Chang W, Cramer HH, Hindemith C, Randel H, Weyhermüller T, Farès C, Werlé C. An Adaptive Rhodium Catalyst to Control the Hydrogenation Network of Nitroarenes. Angew Chem Int Ed Engl 2022; 61:e202205515. [PMID: 35759682 PMCID: PMC9544374 DOI: 10.1002/anie.202205515] [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: 04/14/2022] [Indexed: 11/10/2022]
Abstract
An adaptive catalytic system that provides control over the nitroarene hydrogenation network to prepare a wide range of aniline and hydroxylamine derivatives is presented. This system takes advantage of a delicate interplay between a rhodium(III) center and a Lewis acidic borane introduced in the secondary coordination sphere of the metal. The high chemoselectivity of the catalyst in the presence of various potentially vulnerable functional groups and its readiness to be deployed at a preparative scale illustrate its practicality. Mechanistic studies and density functional theory (DFT) methods were used to shed light on the mode of functioning of the catalyst and elucidate the origin of adaptivity. The competition for interaction with boron between a solvent molecule and a substrate was found crucial for adaptivity. When operating in THF, the reduction network stops at the hydroxylamine platform, whereas the reaction can be directed to the aniline platform in toluene.
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Affiliation(s)
- Vishal Chugh
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
| | - Basujit Chatterjee
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
| | - Wei‐Chieh Chang
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
| | - Hanna H. Cramer
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
| | - Carsten Hindemith
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
| | - Helena Randel
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
| | - Thomas Weyhermüller
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
| | - Christophe Farès
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Germany
| | - Christophe Werlé
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34–36 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum Universitätsstr. 150 44801 Bochum Germany
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47
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Hafeez J, Bilal M, Rasool N, Hafeez U, Adnan Ali Shah S, Imran S, Amiruddin Zakaria Z. Synthesis of Ruthenium complexes and their catalytic applications: A review. ARAB J CHEM 2022. [DOI: 10.1016/j.arabjc.2022.104165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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48
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Fan Q, Zhang H, Ren H, He Y, Gu Y, Wu G, Zhu H, Xie Z, Le Z. Photocatalyst-free light driven dehydrogenation of alcohols into carbonyl compounds under mild conditions. Chem Asian J 2022; 17:e202200468. [PMID: 35833628 DOI: 10.1002/asia.202200468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 07/03/2022] [Indexed: 11/08/2022]
Abstract
Herein, we reported a photocatalyst-free, facile and eco-friendly method for conducting dehydrogenation of alcohols to corresponding aldehydes or ketones with high selectivity under mild conditions. The methodology exhibited outstanding tolerance with electron-donating and electron-withdrawing groups and afforded series of aldehydes or ketones in considerable yields. Furthermore, the plausible mechanism was investigated by control experiments and DFT calculations. The advantages of readily accessible, atomic economy and green reaction conditions for the present method will endow it with prospective application in chemical synthesis.
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Affiliation(s)
- Qiangwen Fan
- East China University of Technology, Jiangxi Province Key laboratory of Synthetic Chemistry, Guanglan Street No.418, Nanchang, Jiangxi Province, 330013, NanChang, CHINA
| | - Honglei Zhang
- East China University of Technology, Jiangxi Province Key Laboratory of Synthetic Chemistry, CHINA
| | - Huijun Ren
- East China University of Technology, Jiangxi Province Key Laboratory of Synthetic Chemistry, CHINA
| | - Yanling He
- East China University of Technology, Jiangxi Province Key Laboratory of Synthetic Chemistry, CHINA
| | - Yuhang Gu
- East China University of Technology, Jiangxi Province Key Laboratory of Synthetic Chemistry, CHINA
| | - Guorong Wu
- East China University of Technology, Jiangxi Province Key Laboratory of Synthetic Chemistry, CHINA
| | - Haibo Zhu
- East China University of Technology, Jiangxi Province Key Laboratory of Synthetic Chemistry, CHINA
| | - Zongbo Xie
- East China University of Technology, Jiangxi Province Key Laboratory of Synthetic Chemistry, CHINA
| | - Zhanggao Le
- East China University of Technology, Jiangxi Province Key Laboratory of Synthetic Chemistry, CHINA
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49
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Roque JB, Pabst TP, Chirik PJ. C(sp 2)–H Activation with Bis(silylene)pyridine Cobalt(III) Complexes: Catalytic Hydrogen Isotope Exchange of Sterically Hindered C–H Bonds. ACS Catal 2022; 12:8877-8885. [PMID: 36032506 PMCID: PMC9401092 DOI: 10.1021/acscatal.2c02429] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The bis(silylene)pyridine cobalt(III) dihydride boryl, trans-[ ptol SiNSi]Co(H)2BPin (ptolSiNSi = 2,6-[EtNSi(NtBu)2CAr]2 C5H3N, where Ar = C6H5CH3, and Pin =pinacolato) has been used as a precatalyst for the hydrogen isotope exchange (HIE) of arenes and heteroarenes using benzene-d 6 as the deuterium source. Use of D2 as the source of the isotope produced modest levels of deuterium incorporation and stoichiometric studies established modification of the pincer ligand through irreversible addition of H2 across the silylene leading to catalyst deactivation. High levels of deuterium incorporation were observed with benzene-d 6 as the isotope source and enabled low (0.5 - 5 mol%) loadings of the cobalt precursor. The resulting high activity for C-H activation enabled deuterium incorporation at sterically encumbered sites previously inaccessible with first-row metal HIE catalysts. The cobalt-catalyzed method was also compatible with aryl halides, demonstrating a kinetic preference for chemoselective C(sp2)-H activation over C(sp2)-X (X = Cl, Br) bonds. Monitoring the catalytic reaction by NMR spectroscopy established cobalt(III) resting states at both low and high conversions of substrate and the overall performance was inhibited by the addition of HBPin. Studies on precatalyst activation with cis-[ ptol SiNSi]Co(Bf)2H and cis-[ ptol SiNSi]Co(H)2Bf (where Bf = 2-benzofuranyl), support the intermediacy of bis(hydride)aryl cobalt intermediates as opposed to bis(aryl)hydride cobalt complexes in the catalytic HIE method. Mechanistic insights resulted in an improved protocol using [ ptol SiNSi]Co(H)3 NaBHEt3 as the precatalyst, ultimately translating onto higher levels of isotopic incorporation.
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Affiliation(s)
- Jose B. Roque
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Tyler P. Pabst
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Paul J. Chirik
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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Chugh V, Chatterjee B, Chang WC, Cramer HH, Hindemith C, Randel H, Weyhermüller T, Farès C, Werlé C. An Adaptive Rhodium Catalyst to Control the Hydrogenation Network of Nitroarenes. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202205515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Vishal Chugh
- Max-Planck-Institute for Chemical Energy Conversion: Max-Planck-Institut fur chemische Energiekonversion Synergistic Organometallic Catalysis GERMANY
| | - Basujit Chatterjee
- Max-Planck-Institute for Chemical Energy Conversion: Max-Planck-Institut fur chemische Energiekonversion Synergistic Organometallic Catalysis GERMANY
| | - Wei-Chieh Chang
- Max-Planck-Institute for Chemical Energy Conversion: Max-Planck-Institut fur chemische Energiekonversion Synergistic Organometallic Catalysis GERMANY
| | - Hanna H. Cramer
- Max-Planck-Institute for Chemical Energy Conversion: Max-Planck-Institut fur chemische Energiekonversion Synergistic Organometallic Catalysis GERMANY
| | - Carsten Hindemith
- Max-Planck-Institute for Chemical Energy Conversion: Max-Planck-Institut fur chemische Energiekonversion Synergistic Organometallic Catalysis GERMANY
| | - Helena Randel
- Max-Planck-Institute for Chemical Energy Conversion: Max-Planck-Institut fur chemische Energiekonversion Synergistic Organometallic Catalysis GERMANY
| | - Thomas Weyhermüller
- Max-Planck-Institute for Chemical Energy Conversion: Max-Planck-Institut fur chemische Energiekonversion Anorganische Spektroskopie GERMANY
| | - Christophe Farès
- Max-Planck-Institute für Kohlenforschung: Max-Planck-Institut fur Kohlenforschung Nuclear Magnetic Resonance Spectroscopy GERMANY
| | - Christophe Werlé
- Max-Planck-Institut fur chemische Energiekonversion Synergistic Organometallic Catalysis Stiftstrasse 34 - 36 D - 45470 Mülheim an der Ruhr GERMANY
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