1
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Hurst MR, Zakharov LN, Cook AK. The mechanism of oxidative addition of Pd(0) to Si-H bonds: electronic effects, reaction mechanism, and hydrosilylation. Chem Sci 2021; 12:13045-13060. [PMID: 34745535 PMCID: PMC8513848 DOI: 10.1039/d1sc04419b] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 09/03/2021] [Indexed: 12/12/2022] Open
Abstract
The oxidative addition of Pd to Si-H bonds is a crucial step in a variety of catalytic applications, and many aspects of this reaction are poorly understood. One important yet underexplored aspect is the electronic effect of silane substituents on reactivity. Herein we describe a systematic investigation of the formation of silyl palladium hydride complexes as a function of silane identity, focusing on electronic influence of the silanes. Using [(μ-dcpe)Pd]2 (dcpe = dicyclohexyl(phosphino)ethane) and tertiary silanes, data show that equilibrium strongly favours products formed from electron-deficient silanes, and is fully dynamic with respect to both temperature and product distribution. A notable kinetic isotope effect (KIE) of 1.21 is observed with H/DSiPhMe2 at 233 K, and the reaction is shown to be 0.5th order in [(μ-dcpe)Pd]2 and 1st order in silane. Formed complexes exhibit temperature-dependent intramolecular H/Si ligand exchange on the NMR timescale, allowing determination of the energetic barrier to reversible oxidative addition. Taken together, these results give unique insight into the individual steps of oxidative addition and suggest the initial formation of a σ-complex intermediate to be rate-limiting. The insight gained from these mechanistic studies was applied to hydrosilylation of alkynes, which shows parallel trends in the effect of the silanes' substituents. Importantly, this work highlights the relevance of in-depth mechanistic studies of fundamental steps to catalysis.
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Affiliation(s)
- Michael R Hurst
- Department of Chemistry and Biochemistry, University of Oregon Eugene OR 97403 USA
| | - Lev N Zakharov
- Department of Chemistry and Biochemistry, University of Oregon Eugene OR 97403 USA
| | - Amanda K Cook
- Department of Chemistry and Biochemistry, University of Oregon Eugene OR 97403 USA
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2
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Corbin DA, McCarthy BG, van de Lindt Z, Miyake GM. Radical Cations of Phenoxazine and Dihydrophenazine Photoredox Catalysts and Their Role as Deactivators in Organocatalyzed Atom Transfer Radical Polymerization. Macromolecules 2021; 54:4726-4738. [PMID: 34483367 PMCID: PMC8411649 DOI: 10.1021/acs.macromol.1c00640] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Radical cations of photoredox catalysts used in organocatalyzed atom transfer radical polymerization (O-ATRP) have been synthesized and investigated to gain insight into deactivation in O-ATRP. The stability and reactivity of these compounds were studied in two solvents, N,N-dimethylacetamide and ethyl acetate, to identify possible side reactions in O-ATRP and to investigate the ability of these radical cations to deactivate alkyl radicals. A number of other factors that could influence deactivation in O-ATRP were also probed, such as ion pairing with the radical cations, radical cation oxidation potential, and halide oxidation potential. Ultimately, these studies enabled radical cations to be employed as reagents during O-ATRP to demonstrate improvements in polymerization control with increasing radical cation concentrations. In the polymerization of acrylates, this approach enabled superior molecular weight control, a decrease in polymer dispersity from 1.90 to 1.44, and an increase in initiator efficiency from 78 to 102%. This work highlights the importance of understanding the mechanism and side reactions of O-ATRP, as well as the importance of catalyst radical cations for successful O-ATRP.
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Affiliation(s)
- Daniel A Corbin
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
| | - Blaine G McCarthy
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
| | - Zach van de Lindt
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
| | - Garret M Miyake
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, United States
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3
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Ruiz‐Castañeda M, Santos L, Manzano BR, Espino G, Jalón FA. A Water/Toluene Biphasic Medium Improves Yields and Deuterium Incorporation into Alcohols in the Transfer Hydrogenation of Aldehydes. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Margarita Ruiz‐Castañeda
- Facultad de Ciencias y Tecnologías Químicas-IRICA University of Castilla-La Mancha Avda. C. J. Cela, 10 13071 Ciudad Real Spain
| | - Lucía Santos
- Facultad de Ciencias y Tecnologías Químicas-IRICA University of Castilla-La Mancha Avda. C. J. Cela, 10 13071 Ciudad Real Spain
| | - Blanca R. Manzano
- Facultad de Ciencias y Tecnologías Químicas-IRICA University of Castilla-La Mancha Avda. C. J. Cela, 10 13071 Ciudad Real Spain
| | - Gustavo Espino
- Departamento de Química Facultad de Ciencias University of Burgos Plaza Misael Bañuelos s/n 09001 Burgos Spain
| | - Félix A. Jalón
- Facultad de Ciencias y Tecnologías Químicas-IRICA University of Castilla-La Mancha Avda. C. J. Cela, 10 13071 Ciudad Real Spain
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4
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Garhwal S, Kaushansky A, Fridman N, Shimon LJW, Ruiter GD. Facile H/D Exchange at (Hetero)Aromatic Hydrocarbons Catalyzed by a Stable Trans-Dihydride N-Heterocyclic Carbene (NHC) Iron Complex. J Am Chem Soc 2020; 142:17131-17139. [PMID: 32902969 PMCID: PMC7586338 DOI: 10.1021/jacs.0c07689] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
![]()
Earth-abundant
metal pincer complexes have played an important
role in homogeneous catalysis during the last ten years. Yet, despite
intense research efforts, the synthesis of iron PCcarbeneP pincer complexes has so far remained elusive. Here we report the
synthesis of the first PCNHCP functionalized iron complex
[(PCNHCP)FeCl2] (1) and the reactivity
of the corresponding trans-dihydride iron(II) dinitrogen
complex [(PCNHCP)Fe(H)2N2)] (2). Complex 2 is stable under an atmosphere of
N2 and is highly active for hydrogen isotope exchange at
(hetero)aromatic hydrocarbons under mild conditions (50 °C, N2). With benzene-d6 as the deuterium
source, easily reducible functional groups such as esters and amides
are well tolerated, contributing to the overall wide substrate scope
(e.g., halides, ethers, and amines). DFT studies suggest a complex
assisted σ-bond metathesis pathway for C(sp2)–H
bond activation, which is further discussed in this study.
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Affiliation(s)
- Subhash Garhwal
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, 3200008 Haifa, Israel
| | - Alexander Kaushansky
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, 3200008 Haifa, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, 3200008 Haifa, Israel
| | - Linda J W Shimon
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Graham de Ruiter
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Technion City, 3200008 Haifa, Israel
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5
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Iridium Catalysts for Hydrogen Isotope Exchange. TOP ORGANOMETAL CHEM 2020. [DOI: 10.1007/3418_2020_58] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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6
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7
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Shevchenko VP, Nagaev IY, Myasoedov NF. Effect of Processes Occurring in the Presence of Metal Catalysts on the Main Characteristics of the Hydrogen Isotope Labeled Organic Compounds Obtained. RADIOCHEMISTRY 2019. [DOI: 10.1134/s1066362219030019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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8
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Zhang Y, Karunananda MK, Yu HC, Clark KJ, Williams W, Mankad NP, Ess DH. Dynamically Bifurcating Hydride Transfer Mechanism and Origin of Inverse Isotope Effect for Heterodinuclear AgRu-Catalyzed Alkyne Semihydrogenation. ACS Catal 2019. [DOI: 10.1021/acscatal.8b04130] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Ying Zhang
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
| | - Malkanthi K. Karunananda
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Hsien-Cheng Yu
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Kyle J. Clark
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
| | - Wendy Williams
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
| | - Neal P. Mankad
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Daniel H. Ess
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
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9
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Maduka Ogba O, Liu Z, O'Leary DJ. Vibrational analysis of a rate-slowing conformational kinetic isotope effect. Tetrahedron 2019. [DOI: 10.1016/j.tet.2018.12.051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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10
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Affiliation(s)
- Aaron Sattler
- Corporate Strategic Research, ExxonMobil Research & Engineering Company, 1545 Route 22 East, Annandale, New Jersey 08801, United States
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11
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Atzrodt J, Derdau V, Kerr WJ, Reid M. Methoden der C-H-Funktionalisierung für den Wasserstoffisotopenaustausch. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201708903] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Jens Atzrodt
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry; Industriepark Höchst, G876 65926 Frankfurt Deutschland
| | - Volker Derdau
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry; Industriepark Höchst, G876 65926 Frankfurt Deutschland
| | - William J. Kerr
- Department of Pure and Applied Chemistry, WestCHEM; University of Strathclyde; 295 Cathedral Street Glasgow Scotland G1 1XL Großbritannien
| | - Marc Reid
- Department of Pure and Applied Chemistry, WestCHEM; University of Strathclyde; 295 Cathedral Street Glasgow Scotland G1 1XL Großbritannien
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12
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Atzrodt J, Derdau V, Kerr WJ, Reid M. C-H Functionalisation for Hydrogen Isotope Exchange. Angew Chem Int Ed Engl 2018; 57:3022-3047. [PMID: 29024330 DOI: 10.1002/anie.201708903] [Citation(s) in RCA: 307] [Impact Index Per Article: 51.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Indexed: 11/06/2022]
Abstract
The various applications of hydrogen isotopes (deuterium, D, and tritium, T) in the physical and life sciences demand a range of methods for their installation in an array of molecular architectures. In this Review, we describe recent advances in synthetic C-H functionalisation for hydrogen isotope exchange.
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Affiliation(s)
- Jens Atzrodt
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry, Industriepark Höchst, G876, 65926, Frankfurt, Germany
| | - Volker Derdau
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry, Industriepark Höchst, G876, 65926, Frankfurt, Germany
| | - William J Kerr
- Department of Pure and Applied Chemistry, WestCHEM, University of Strathclyde, 295 Cathedral Street, Glasgow, Scotland, G1 1XL, UK
| | - Marc Reid
- Department of Pure and Applied Chemistry, WestCHEM, University of Strathclyde, 295 Cathedral Street, Glasgow, Scotland, G1 1XL, UK
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13
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Atzrodt J, Derdau V, Kerr WJ, Reid M. Deuterium- und tritiummarkierte Verbindungen: Anwendungen in den modernen Biowissenschaften. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201704146] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Jens Atzrodt
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry; Industriepark Höchst, G876 65926 Frankfurt Deutschland
| | - Volker Derdau
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry; Industriepark Höchst, G876 65926 Frankfurt Deutschland
| | - William J. Kerr
- Department of Pure and Applied Chemistry, WestCHEM; University of Strathclyde; 295 Cathedral Street Glasgow Scotland G1 1XL Großbritannien
| | - Marc Reid
- Department of Pure and Applied Chemistry, WestCHEM; University of Strathclyde; 295 Cathedral Street Glasgow Scotland G1 1XL Großbritannien
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14
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Atzrodt J, Derdau V, Kerr WJ, Reid M. Deuterium- and Tritium-Labelled Compounds: Applications in the Life Sciences. Angew Chem Int Ed Engl 2018; 57:1758-1784. [PMID: 28815899 DOI: 10.1002/anie.201704146] [Citation(s) in RCA: 407] [Impact Index Per Article: 67.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 07/27/2017] [Indexed: 12/19/2022]
Abstract
Hydrogen isotopes are unique tools for identifying and understanding biological and chemical processes. Hydrogen isotope labelling allows for the traceless and direct incorporation of an additional mass or radioactive tag into an organic molecule with almost no changes in its chemical structure, physical properties, or biological activity. Using deuterium-labelled isotopologues to study the unique mass-spectrometric patterns generated from mixtures of biologically relevant molecules drastically simplifies analysis. Such methods are now providing unprecedented levels of insight in a wide and continuously growing range of applications in the life sciences and beyond. Tritium (3 H), in particular, has seen an increase in utilization, especially in pharmaceutical drug discovery. The efforts and costs associated with the synthesis of labelled compounds are more than compensated for by the enhanced molecular sensitivity during analysis and the high reliability of the data obtained. In this Review, advances in the application of hydrogen isotopes in the life sciences are described.
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Affiliation(s)
- Jens Atzrodt
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry, Industriepark Höchst, G876, 65926, Frankfurt, Germany
| | - Volker Derdau
- Isotope Chemistry and Metabolite Synthesis, Integrated Drug Discovery, Medicinal Chemistry, Industriepark Höchst, G876, 65926, Frankfurt, Germany
| | - William J Kerr
- Department of Pure and Applied Chemistry, WestCHEM, University of Strathclyde, 295 Cathedral Street, Glasgow, Scotland, G1 1XL, UK
| | - Marc Reid
- Department of Pure and Applied Chemistry, WestCHEM, University of Strathclyde, 295 Cathedral Street, Glasgow, Scotland, G1 1XL, UK
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15
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Bellows SM, Arnet NA, Gurubasavaraj PM, Brennessel WW, Bill E, Cundari TR, Holland PL. The Mechanism of N-N Double Bond Cleavage by an Iron(II) Hydride Complex. J Am Chem Soc 2016; 138:12112-23. [PMID: 27598037 PMCID: PMC5499983 DOI: 10.1021/jacs.6b04654] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The use of hydride species for substrate reductions avoids strong reductants, and may enable nitrogenase to reduce multiple bonds without unreasonably low redox potentials. In this work, we explore the N═N bond cleaving ability of a high-spin iron(II) hydride dimer with concomitant release of H2. Specifically, this diiron(II) complex reacts with azobenzene (PhN═NPh) to perform a four-electron reduction, where two electrons come from H2 reductive elimination and the other two come from iron oxidation. The rate law of the H2 releasing reaction indicates that diazene binding occurs prior to H2 elimination, and the negative entropy of activation and inverse kinetic isotope effect indicate that H-H bond formation is the rate-limiting step. Thus, substrate binding causes reductive elimination of H2 that formally reduces the metals, and the metals use the additional two electrons to cleave the N-N multiple bond.
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Affiliation(s)
- Sarina M. Bellows
- Department of Chemistry, University of Rochester, Rochester, NY 14627
| | | | | | | | - Eckhard Bill
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, Mülheim an der Ruhr, Germany
| | - Thomas R. Cundari
- Department of Chemistry and CASCaM, University of North Texas, Denton, TX 76203
| | - Patrick L. Holland
- Department of Chemistry, University of Rochester, Rochester, NY 14627
- Department of Chemistry, Yale University, New Haven, CT 06520
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16
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Lukoyanov D, Khadka N, Yang ZY, Dean DR, Seefeldt LC, Hoffman BM. Reversible Photoinduced Reductive Elimination of H2 from the Nitrogenase Dihydride State, the E(4)(4H) Janus Intermediate. J Am Chem Soc 2016; 138:1320-7. [PMID: 26788586 DOI: 10.1021/jacs.5b11650] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We recently demonstrated that N2 reduction by nitrogenase involves the obligatory release of one H2 per N2 reduced. These studies focus on the E4(4H) "Janus intermediate", which has accumulated four reducing equivalents as two [Fe-H-Fe] bridging hydrides. E4(4H) is poised to bind and reduce N2 through reductive elimination (re) of the two hydrides as H2, coupled to the binding/reduction of N2. To obtain atomic-level details of the re activation process, we carried out in situ 450 nm photolysis of E4(4H) in an EPR cavity at temperatures below 20 K. ENDOR and EPR measurements show that photolysis generates a new FeMo-co state, denoted E4(2H)*, through the photoinduced re of the two bridging hydrides of E4(4H) as H2. During cryoannealing at temperatures above 175 K, E4(2H)* reverts to E4(4H) through the oxidative addition (oa) of the H2. The photolysis quantum yield is temperature invariant at liquid helium temperatures and shows a rather large kinetic isotope effect, KIE = 10. These observations imply that photoinduced release of H2 involves a barrier to the combination of the two nascent H atoms, in contrast to a barrierless process for monometallic inorganic complexes, and further suggest that H2 formation involves nuclear tunneling through that barrier. The oa recombination of E4(2H)* with the liberated H2 offers compelling evidence for the Janus intermediate as the point at which H2 is necessarily lost during N2 reduction; this mechanistically coupled loss must be gated by N2 addition that drives the re/oa equilibrium toward reductive elimination of H2 with N2 binding/reduction.
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Affiliation(s)
- Dmitriy Lukoyanov
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
| | - Nimesh Khadka
- Department of Chemistry and Biochemistry, Utah State University , Logan, Utah 84322, United States
| | - Zhi-Yong Yang
- Department of Chemistry and Biochemistry, Utah State University , Logan, Utah 84322, United States
| | - Dennis R Dean
- Department of Biochemistry, Virginia Tech , Blacksburg, Virginia 24061, United States
| | - Lance C Seefeldt
- Department of Chemistry and Biochemistry, Utah State University , Logan, Utah 84322, United States
| | - Brian M Hoffman
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
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17
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The Covalent Bond Classification Method and Its Application to Compounds That Feature 3-Center 2-Electron Bonds. THE CHEMICAL BOND III 2016. [DOI: 10.1007/430_2015_206] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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18
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Doyle LE, Piers WE, Borau-Garcia J, Sgro MJ, Spasyuk DM. Mechanistic studies on the addition of hydrogen to iridaepoxide complexes with subsequent elimination of water. Chem Sci 2015; 7:921-931. [PMID: 30155011 PMCID: PMC6090529 DOI: 10.1039/c5sc03575a] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 10/26/2015] [Indexed: 02/03/2023] Open
Abstract
Iridium complexes of the PCsp2P ligand in which the donors are linked by 2,3-benzo[b]thiophene groups engage in the cooperative activation of N2O and the resulting iridaepoxides can be treated with dihydrogen to effect elimination of water and regeneration of the starting iridium complex.
Iridium complexes of the PCsp2P ligand in which the donors are linked by 2,3-benzo[b]thiophene groups engage in the cooperative activation of N2O and the resulting iridaepoxides can be treated with dihydrogen to effect elimination of water and regeneration of the starting iridium complex. The mechanism of the steps in this reaction have been investigated using low temperature NMR investigations that reveal H/D exchange processes that point to a highly reactive kinetic product of hydrogen addition to the iridaepoxide. This intermediate is also involved in the water elimination pathway, and model compounds have been synthesized to provide further evidence for the mechanistic proposals for water elimination. The adaptable donor properties of the PCsp2P ligand framework, particularly the anchoring carbene donor, plays a significant role in the ability of these compounds to mediate the transformation of N2O in this way.
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Affiliation(s)
- Lauren E Doyle
- University of Calgary , Department of Chemistry , 2500 University Drive N.W. , Calgary , Alberta T2N 1N4 , Canada .
| | - Warren E Piers
- University of Calgary , Department of Chemistry , 2500 University Drive N.W. , Calgary , Alberta T2N 1N4 , Canada .
| | - Javier Borau-Garcia
- University of Calgary , Department of Chemistry , 2500 University Drive N.W. , Calgary , Alberta T2N 1N4 , Canada .
| | - Michael J Sgro
- University of Calgary , Department of Chemistry , 2500 University Drive N.W. , Calgary , Alberta T2N 1N4 , Canada .
| | - Denis M Spasyuk
- University of Calgary , Department of Chemistry , 2500 University Drive N.W. , Calgary , Alberta T2N 1N4 , Canada .
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19
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Devlin J, Kerr WJ, Lindsay DM, McCabe TJD, Reid M, Tuttle T. Iridium-Catalysed ortho-Directed Deuterium Labelling of Aromatic Esters--An Experimental and Theoretical Study on Directing Group Chemoselectivity. Molecules 2015; 20:11676-98. [PMID: 26121395 PMCID: PMC6332247 DOI: 10.3390/molecules200711676] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 06/17/2015] [Accepted: 06/19/2015] [Indexed: 01/29/2023] Open
Abstract
Herein we report a combined experimental and theoretical study on the deuterium labelling of benzoate ester derivatives, utilizing our developed iridium N-heterocyclic carbene/phosphine catalysts. A range of benzoate esters were screened, including derivatives with electron-donating and -withdrawing groups in the para- position. The substrate scope, in terms of the alkoxy group, was studied and the nature of the catalyst counter-ion was shown to have a profound effect on the efficiency of isotope exchange. Finally, the observed chemoselectivity was rationalized by rate studies and theoretical calculations, and this insight was applied to the selective labelling of benzoate esters bearing a second directing group.
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Affiliation(s)
- Jennifer Devlin
- Department of Pure & Applied Chemistry, University of Strathclyde, WestCHEM, 295 Cathedral Street, Glasgow G1 1XL, UK.
| | - William J Kerr
- Department of Pure & Applied Chemistry, University of Strathclyde, WestCHEM, 295 Cathedral Street, Glasgow G1 1XL, UK.
| | - David M Lindsay
- Department of Pure & Applied Chemistry, University of Strathclyde, WestCHEM, 295 Cathedral Street, Glasgow G1 1XL, UK.
| | - Timothy J D McCabe
- Department of Pure & Applied Chemistry, University of Strathclyde, WestCHEM, 295 Cathedral Street, Glasgow G1 1XL, UK.
| | - Marc Reid
- Department of Pure & Applied Chemistry, University of Strathclyde, WestCHEM, 295 Cathedral Street, Glasgow G1 1XL, UK.
| | - Tell Tuttle
- Department of Pure & Applied Chemistry, University of Strathclyde, WestCHEM, 295 Cathedral Street, Glasgow G1 1XL, UK.
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20
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Doyle LE, Piers WE, Borau-Garcia J. Ligand Cooperation in the Formal Hydrogenation of N2O Using a PCsp2P Iridium Pincer Complex. J Am Chem Soc 2015; 137:2187-90. [DOI: 10.1021/ja512602m] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Lauren E. Doyle
- Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - Warren E. Piers
- Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
| | - Javier Borau-Garcia
- Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta T2N 1N4, Canada
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21
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Zamorano A, Rendón N, López-Serrano J, Valpuesta JEV, Álvarez E, Carmona E. Dihydrogen Catalysis of the Reversible Formation and Cleavage of CH and NH Bonds of Aminopyridinate Ligands Bound to (η5-C5Me5)IrIII. Chemistry 2014; 21:2576-87. [DOI: 10.1002/chem.201405340] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Indexed: 11/06/2022]
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22
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Scheller S, Goenrich M, Thauer RK, Jaun B. Methyl-coenzyme M reductase from methanogenic archaea: isotope effects on label exchange and ethane formation with the homologous substrate ethyl-coenzyme M. J Am Chem Soc 2013; 135:14985-95. [PMID: 24003767 DOI: 10.1021/ja4064876] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ethyl-coenzyme M (CH3CH2-S-CH2CH2-SO3(-), Et-S-CoM) serves as a homologous substrate for the enzyme methyl-coenzyme M reductase (MCR) resulting in the product ethane instead of methane. The catalytic reaction proceeds via an intermediate that already contains all six C-H bonds of the product. Because product release occurs after a second, rate-limiting step, many cycles of intermediate formation and reconversion to substrate occur before a substantial amount of ethane is released. In deuterated buffer, the intermediate becomes labeled, and C-H activation in the back reaction rapidly leads to labeled Et-S-CoM, which enables intermediate formation to be detected. Here, we present a comprehensive analysis of this pre-equilibrium. (2)H- and (13)C-labeled isotopologues of Et-S-CoM were used as the substrates, and the time course of each isotopologue was followed by NMR spectroscopy. A kinetic simulation including kinetic isotope effects allowed determination of the primary and α- and β-secondary isotope effects for intermediate formation and for the C-H/C-D bond activation in the ethane-containing intermediate. The values obtained are in accordance with those found for the native substrate Me-S-CoM (see preceding publication, Scheller, S.; Goenrich, M.; Thauer, R. K.; Jaun, B. J. Am. Chem. Soc. 2013, 135, DOI: 10.1021/ja406485z) and thus imply the same catalytic mechanism for both substrates. The experiment by Floss and co-workers, demonstrating a net inversion of configuration to chiral ethane with CH3CDT-S-CoM as the substrate, is compatible with the observed rapid isotope exchange if the isotope effects measured here are taken into account.
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Affiliation(s)
- Silvan Scheller
- Laboratory of Organic Chemistry, ETH Zurich , Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland
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Fong A, Meyer MP, O’Leary DJ. Enthalpy/entropy contributions to conformational KIEs: theoretical predictions and comparison with experiment. Molecules 2013; 18:2281-96. [PMID: 23429344 PMCID: PMC6269852 DOI: 10.3390/molecules18022281] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/22/2013] [Accepted: 02/01/2013] [Indexed: 11/16/2022] Open
Abstract
Previous theoretical studies of Mislow’s doubly-bridged biphenyl ketone 1 and dihydrodimethylphenanthrene 2 have determined significant entropic contributions to their normal (1) and inverse (2) conformational kinetic isotope effects (CKIEs). To broaden our investigation, we have used density functional methods to characterize the potential energy surfaces and vibrational frequencies for ground and transition structures of additional systems with measured CKIEs, including [2.2]-metaparacyclophane-d (3), 1,1'-binaphthyl (4), 2,2'-dibromo-[1,1'-biphenyl]-4,4'-dicarboxylic acid (5), and the 2-(N,N,N-trimethyl)-2'-(N,N-dimethyl)-diaminobiphenyl cation (6). We have also computed CKIEs in a number of systems whose experimental CKIEs are unknown. These include analogs of 1 in which the C=O groups have been replaced with CH2 (7), O (8), and S (9) atoms and ring-expanded variants of 2 containing CH2 (10), O (11), S (12), or C=O (13) groups. Vibrational entropy contributes to the CKIEs in all of these systems with the exception of cyclophane 3, whose isotope effect is predicted to be purely enthalpic in origin and whose Bigeleisen-Mayer ZPE term is equivalent to ΔΔH‡. There is variable correspondence between these terms in the other molecules studied, thus identifying additional examples of systems in which the Bigeleisen-Mayer formalism does not correlate with ΔH/ΔS dissections.
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Affiliation(s)
- Aaron Fong
- Department of Chemistry, Pomona College, 645 North College Avenue, Claremont, CA 91711, USA; E-Mail:
| | - Matthew P. Meyer
- Department of Chemistry, University of California, Merced, Atwater, CA 95301, USA
- Authors to whom correspondence should be addressed; E-Mails: (M.P.M.); (D.J.O.); Tel.: +1-209-228-2982 (M.P.M.); Fax: +1-209-228-4646 (M.P.M.); Tel.: +1-909-621-8444 (D.J.O.); Fax: +1-909-607-7726 (D.J.O.)
| | - Daniel J. O’Leary
- Department of Chemistry, Pomona College, 645 North College Avenue, Claremont, CA 91711, USA; E-Mail:
- Authors to whom correspondence should be addressed; E-Mails: (M.P.M.); (D.J.O.); Tel.: +1-209-228-2982 (M.P.M.); Fax: +1-209-228-4646 (M.P.M.); Tel.: +1-909-621-8444 (D.J.O.); Fax: +1-909-607-7726 (D.J.O.)
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24
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Pelton EJ, Blank DA, McNeill K. Dechlorination of chlorinated ethylenes by a photochemically generated iron(0) complex. Dalton Trans 2013; 42:10121-8. [DOI: 10.1039/c3dt50693b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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Ahmadi Z, McIndoe JS. A mechanistic investigation of hydrodehalogenation using ESI-MS. Chem Commun (Camb) 2013; 49:11488-90. [DOI: 10.1039/c3cc46271d] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Grellier M, Mason SA, Albinati A, Capelli SC, Rizzato S, Bijani C, Coppel Y, Sabo-Etienne S. Probing Highly Selective H/D Exchange Processes with a Ruthenium Complex through Neutron Diffraction and Multinuclear NMR Studies. Inorg Chem 2012; 52:7329-37. [DOI: 10.1021/ic302307m] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Mary Grellier
- CNRS, LCC (Laboratoire de Chimie de Coordination),
205 route de Narbonne, BP 44099, F-31077 Toulouse Cedex 4, France
- Université de Toulouse, UPS, INPT, F-31077 Toulouse Cedex 4, France
| | - Sax A. Mason
- Institut Laue-Langevin, 6 rue Jules Horowitz, BP 156, 38042 Grenoble Cedex 9, France
| | - Alberto Albinati
- Dipartimento di Chimica, Università di Milano, Via C. Golgi, 19, 20133
Milan, Italy
| | - Silvia C. Capelli
- Institut Laue-Langevin, 6 rue Jules Horowitz, BP 156, 38042 Grenoble Cedex 9, France
| | - Silvia Rizzato
- Dipartimento di Chimica, Università di Milano, Via C. Golgi, 19, 20133
Milan, Italy
| | - Christian Bijani
- CNRS, LCC (Laboratoire de Chimie de Coordination),
205 route de Narbonne, BP 44099, F-31077 Toulouse Cedex 4, France
- Université de Toulouse, UPS, INPT, F-31077 Toulouse Cedex 4, France
| | - Yannick Coppel
- CNRS, LCC (Laboratoire de Chimie de Coordination),
205 route de Narbonne, BP 44099, F-31077 Toulouse Cedex 4, France
- Université de Toulouse, UPS, INPT, F-31077 Toulouse Cedex 4, France
| | - Sylviane Sabo-Etienne
- CNRS, LCC (Laboratoire de Chimie de Coordination),
205 route de Narbonne, BP 44099, F-31077 Toulouse Cedex 4, France
- Université de Toulouse, UPS, INPT, F-31077 Toulouse Cedex 4, France
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Valpuesta JEV, Rendón N, López-Serrano J, Poveda ML, Sánchez L, Álvarez E, Carmona E. Dihydrogen-Catalyzed Reversible Carbon-Hydrogen and Nitrogen-Hydrogen Bond Formation in Organometallic Iridium Complexes. Angew Chem Int Ed Engl 2012; 51:7555-7. [DOI: 10.1002/anie.201201811] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 05/02/2012] [Indexed: 11/06/2022]
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28
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Valpuesta JEV, Rendón N, López-Serrano J, Poveda ML, Sánchez L, Álvarez E, Carmona E. Dihydrogen-Catalyzed Reversible Carbon-Hydrogen and Nitrogen-Hydrogen Bond Formation in Organometallic Iridium Complexes. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201201811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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29
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Dudle B, Blacque O, Berke H. Ethylene Reactions of a [ReH(η2-BH4)(NO)(PPh3)2] Complex: Reductive Elimination of Ethane and Oxidative Coupling to Butadiene. Organometallics 2012. [DOI: 10.1021/om201187w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Balz Dudle
- Institute of Inorganic
Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich
| | - Olivier Blacque
- Institute of Inorganic
Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich
| | - Heinz Berke
- Institute of Inorganic
Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich
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30
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Green JC, Green MLH, Parkin G. The occurrence and representation of three-centre two-electron bonds in covalent inorganic compounds. Chem Commun (Camb) 2012; 48:11481-503. [DOI: 10.1039/c2cc35304k] [Citation(s) in RCA: 222] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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31
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Rudakov ES, Lobachev VL, Volkova LK. Cage effect and inverse temperature dependence of the kinetic isotope effect in the c-C6H12/c-C6D12 reaction with OH radicals in fenton and HOONOH2O systems. INT J CHEM KINET 2011. [DOI: 10.1002/kin.20588] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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32
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Dudle B, Rajesh K, Blacque O, Berke H. Rhenium in Homogeneous Catalysis: [ReBrH(NO)(labile ligand)(large-bite-angle diphosphine)] Complexes as Highly Active Catalysts in Olefin Hydrogenations. J Am Chem Soc 2011; 133:8168-78. [DOI: 10.1021/ja107245k] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Balz Dudle
- Institute of Inorganic Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich
| | - Kunjanpillai Rajesh
- Institute of Inorganic Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich
| | - Olivier Blacque
- Institute of Inorganic Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich
| | - Heinz Berke
- Institute of Inorganic Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich
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Gómez-Gallego M, Sierra MA. Kinetic isotope effects in the study of organometallic reaction mechanisms. Chem Rev 2011; 111:4857-963. [PMID: 21545118 DOI: 10.1021/cr100436k] [Citation(s) in RCA: 521] [Impact Index Per Article: 40.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Mar Gómez-Gallego
- Departamento de Química Orgánica I, Facultad de Química, Universidad Complutense, 28040 Madrid, Spain.
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34
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O'Leary DJ, Rablen PR, Meyer MP. On the Origin of Conformational Kinetic Isotope Effects. Angew Chem Int Ed Engl 2011; 50:2564-7. [DOI: 10.1002/anie.201007322] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Indexed: 11/06/2022]
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35
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O'Leary DJ, Rablen PR, Meyer MP. On the Origin of Conformational Kinetic Isotope Effects. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201007322] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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36
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Perrin CL. Secondary equilibrium isotope effects on acidity. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2010. [DOI: 10.1016/s0065-3160(08)44003-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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37
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Zimmer-De Iuliis M, Morris RH. Kinetic Hydrogen/Deuterium Effects in the Direct Hydrogenation of Ketones Catalyzed by a Well-Defined Ruthenium Diphosphine Diamine Complex. J Am Chem Soc 2009; 131:11263-9. [DOI: 10.1021/ja9043104] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marco Zimmer-De Iuliis
- Davenport Laboratory, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Robert H. Morris
- Davenport Laboratory, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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38
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Parkin G. Temperature-dependent transitions between normal and inverse isotope effects pertaining to the interaction of H-H and C-H bonds with transition metal centers. Acc Chem Res 2009; 42:315-25. [PMID: 19133745 DOI: 10.1021/ar800156h] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Deuterium kinetic isotope effects (KIEs) serve as versatile tools to infer details about reaction mechanisms and the nature of transition states, while equilibrium isotope effects (EIEs) associated with the site preferences of hydrogen and deuterium enable researchers to study aspects of molecular structure. Researchers typically interpret primary deuterium isotope effects based on two simple guidelines: (i) the KIE for an elementary reaction is normal (k(H)/k(D) > 1) and (ii) the EIE is dictated by deuterium preferring to be located in the site corresponding to the highest frequency oscillator. In this Account, we evaluate the applicability of these rules to the interactions of H-H and C-H bonds with a transition metal center. Significantly, experimental and computational studies question the predictability of primary EIEs in these systems based on the notion that deuterium prefers to occupy the highest frequency oscillator. In particular, the EIEs for (i) formation of sigma-complexes by coordination of H-H and C-H bonds and (ii) oxidative addition of dihydrogen exhibit unusual temperature dependencies, such that the same system may demonstrate both normal (i.e., K(H)/K(D) > 1) and inverse (i.e., K(H)/K(D) < 1) values. The transition between a normal and inverse EIE indicates that these systems do not demonstrate the typical monotonic variation predicted by the van't Hoff relationship. Instead, the calculated EIEs in these systems are 0 at 0 K, increase to a value greater than 1, and then decrease to unity at infinite temperature. This unusual behavior may be rationalized by considering the individual factors that contribute to the EIE. Specifically, the EIE may be expressed in the form EIE = SYM x MMI x EXC x ZPE (where SYM is the symmetry factor, MMI is the mass-moment of inertia term, EXC is the excitation term, and ZPE is the zero-point energy term), and the distinctive temperature profile results from the inverse ZPE (enthalpy) and normal [SYM x MMI x EXC] (entropy) components opposing each other and having different temperature dependencies. At low temperatures, the ZPE component dominates and the EIE is inverse, while at high temperatures, the [SYM x MMI x EXC] component dominates and the EIE is normal. The inverse nature of the ZPE term is a consequence of the rotational and translational degrees of freedom of RH (R = H, CH(3)) becoming low-energy isotopically sensitive vibrations in the product, while the normal nature of the [SYM x MMI x EXC] component results from deuterium substitution having a larger impact on the moment of inertia of the smaller molecule.
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Affiliation(s)
- Gerard Parkin
- Department of Chemistry, Columbia University, New York, New York 10027
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Parkin G. Applications of Tripodal [S(3)] and [Se(3)] L(2)X Donor Ligands to Zinc, Cadmium and Mercury Chemistry: Organometallic and Bioinorganic Perspectives. NEW J CHEM 2007; 31:1996-2014. [PMID: 19484137 PMCID: PMC2688380 DOI: 10.1039/b712012e] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The tripodal tris(2-mercapto-1-R-imidazolyl)hydroborato ligand system, [Tm(R)], and its selenium counterpart, [Tse(R)], provide useful platforms for investigating organometallic and bioinorganic aspects of the chemistry of zinc, cadmium and mercury in sulfur-rich and selenium-rich coordination environments. For example, the tridentate [Tm(R)] ligand provides an [S(3)] donor array that is of use for mimicking aspects of zinc enzymes and proteins that have sulfur-rich active sites, such as the Ada DNA repair protein. With respect to mercury, an interesting application of the [Tm(Bu(t) )] ligand is the synthesis of the mercury alkyl compounds [Tm(Bu(t) )]HgR (R = Me, Et) that react with PhSH to yield [Tm(Bu(t) )]HgSPh and RH, a reaction that emulates mercury detoxification by the organomercurial lyase, MerB. In addition to the tridentate [Tm(R)] and [Tse(R)] ligands, applications of the bidentate counterparts, [Bm(R)] and [Bse(R)] are also described.
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Affiliation(s)
- Gerard Parkin
- Department of Chemistry, Columbia University, New York, New York 10027, USA
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