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Acosta-Calle S, Huebsch EZ, Kolmar SS, Whited MT, Chen CH, Miller AJM. Regulating Access to Active Sites via Hydrogen Bonding and Cation-Dipole Interactions: A Dual Cofactor Approach to Switchable Catalysis. J Am Chem Soc 2024. [PMID: 38598724 DOI: 10.1021/jacs.3c10877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
Hydrogen bonding networks are ubiquitous in biological systems and play a key role in controlling the conformational dynamics and allosteric interactions of enzymes. Yet in small organometallic catalysts, hydrogen bonding rarely controls ligand binding to the metal center. In this work, a hydrogen bonding network within a well-defined organometallic catalyst works in concert with cation-dipole interactions to gate substrate access to the active site. An ammine ligand acts as one cofactor, templating a hydrogen bonding network within a pendent crown ether and preventing the binding of strong donor ligands, such as nitriles, to the nickel center. Sodium ions are the second cofactor, disrupting hydrogen bonding to enable switchable ligand substitution reactions. Thermodynamic analyses provide insight into the energetic requirements of the different supramolecular interactions that enable substrate gating. The dual cofactor approach enables switchable catalytic hydroamination of crotononitrile. Systematic comparisons of catalysts with varying structural features provide support for the critical role of the dual cofactors in achieving on/off catalysis with substrates containing strongly donating functional groups that might otherwise interfere with switchable catalysts.
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Affiliation(s)
- Sebastian Acosta-Calle
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Elsa Z Huebsch
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Scott S Kolmar
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Matthew T Whited
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Department of Chemistry, Carleton College, Northfield, Minnesota 55057, United States
| | - Chun-Hsing Chen
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Alexander J M Miller
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
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2
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Pham LD, Smith-Sweetser RO, Krupinsky B, Dewey CE, Lamb JR. Switchable Organocatalysis from N-heterocyclic Carbene-Carbodiimide Adducts with Tunable Release Temperature. Angew Chem Int Ed Engl 2023; 62:e202314376. [PMID: 37824288 DOI: 10.1002/anie.202314376] [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: 09/25/2023] [Revised: 10/10/2023] [Accepted: 10/12/2023] [Indexed: 10/14/2023]
Abstract
N-Heterocyclic carbenes (NHCs) are powerful organocatalysts, but practical applications often require in situ generation from stable precursors that "mask" the NHC reactivity via reversible binding. Previously established "masks" are often simple small molecules, such that the NHC structure is used to control both catalytic activity and activation temperature, leading to undesirable tradeoffs. Herein, we show that NHC-carbodiimide (CDI) adducts can be masked precursors for switchable organocatalysis and that the CDI substituents can control the reaction profile without changing the NHC structure. Large electronic variations on the CDI (e.g., alkyl versus aryl) drastically change the catalytically active temperature, whereas smaller perturbations (e.g., different para-substituted phenyls) tune the catalyst release within a narrower window. This control was demonstrated for three classic NHC-catalyzed reactions, each influencing the NHC-CDI equilibrium in different ways. Our results introduce a new paradigm for controlling NHC organocatalysis as well as present practical considerations for designing appropriate masks for various reactions.
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Affiliation(s)
- Le Dung Pham
- Department of Chemistry, University of Minnesota-Twin Cities, 207 Pleasant Street SE, Minneapolis, MN 55455, USA
| | - Red O Smith-Sweetser
- Department of Chemistry, University of Minnesota-Twin Cities, 207 Pleasant Street SE, Minneapolis, MN 55455, USA
| | - Briana Krupinsky
- Department of Chemistry, University of Minnesota-Twin Cities, 207 Pleasant Street SE, Minneapolis, MN 55455, USA
| | - Carolyn E Dewey
- Department of Chemistry, University of Minnesota-Twin Cities, 207 Pleasant Street SE, Minneapolis, MN 55455, USA
| | - Jessica R Lamb
- Department of Chemistry, University of Minnesota-Twin Cities, 207 Pleasant Street SE, Minneapolis, MN 55455, USA
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3
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Hastings CD, Huffman LSX, Tiwari CK, Betancourth JG, Brennessel WW, Barnett BR. Coordinatively Unsaturated Metallates of Cobalt(II), Nickel(II), and Zinc(II) Guarded by a Rigid and Narrow Void. Inorg Chem 2023; 62:11920-11931. [PMID: 37462947 PMCID: PMC10394664 DOI: 10.1021/acs.inorgchem.3c01335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
Both natural enzymatic systems and synthetic porous material catalysts utilize well-defined and uniform channels to dictate reaction selectivities on the basis of size or shape. Mimicry of this design element in homogeneous systems is generally difficult owing to the flexibility inherent in most small molecular species. Herein, we report the synthesis of a tripodal ligand scaffold that orients a narrow and rigid cavity atop accessible metal coordination space. The permanent void is formed through a macrocyclization reaction whereby the 3,5-dihydroxyphenyl arms are covalently linked through methylene bridges. Deprotonative metallation leads to anionic and coordinatively unsaturated complexes of divalent cobalt, nickel, and zinc. An analogous series of trigonal monopyramidal complexes bearing a nonmacrocyclized variant of the tripodal ligand are also reported. Physical characterization of the coordination complexes has been carried out using multiple spectroscopic techniques (NMR, EPR, and UV-vis), cyclic voltammetry, and X-ray diffraction. Complexes of the macrocyclized [LOCH2O]3- ligand retain a rigid cavity upon metallation, with this cavity guarding the entrance to the open axial coordination site. Through a combination of spectroscopic and computational studies, it is shown that acetonitrile entry into the void is sterically precluded, disrupting anticipated coordination at the intracavity site.
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Affiliation(s)
- Christopher D Hastings
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Lucy S X Huffman
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Chandan Kumar Tiwari
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | | | - William W Brennessel
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Brandon R Barnett
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
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4
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Acosta-Calle S, Miller AJM. Tunable and Switchable Catalysis Enabled by Cation-Controlled Gating with Crown Ether Ligands. Acc Chem Res 2023; 56:971-981. [PMID: 36977400 DOI: 10.1021/acs.accounts.3c00056] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
ConspectusCatalysis has become an essential tool in science and technology, impacting the discovery of pharmaceuticals, the manufacture of commodity chemicals and plastics, the production of fuels, and much more. In most cases, a particular catalyst is optimized to mediate a particular reaction, continually producing a desired product at a given rate. There is enormous opportunity in developing catalysts that are dynamic, capable of responding to a change in the environment to alter structure and function. Controlled catalysis, in which the activity or selectivity of a catalytic reaction can be adjusted through an external stimulus, offers opportunities for innovation in catalysis. Catalyst discovery could be simplified if a single thoughtfully designed complex could work synergistically with additives to optimize performance rather than trying a multitude of different metal/ligand combinations. Temporal control could be gained to facilitate the execution of multiple reactions in the same flask, for example, by activating one catalyst and deactivating another to avoid incompatibilities. Selectivity switching could enable copolymer synthesis with well-defined chemical and material properties. These applications might sound futuristic for synthetic catalysts, but in nature, such a degree of controlled catalysis is commonplace. For example, allosteric interactions and/or feedback loops modulate enzymatic activity to enable complex small-molecule synthesis and sequence-defined polymerization reactions in complex mixtures containing many catalytic sites. In many cases, regulation is achieved by "gating" substrate access to the active site. Fundamental advances in catalyst design are needed to better understand the factors that enable controlled catalysis in the arena of synthetic chemistry, particularly in achieving substrate gating outside of macromolecular environments. In this Account, the development of design principles for achieving cation-controlled catalysis is described. The guiding hypothesis was that gating substrate access to a catalyst site could be achieved by controlling the dynamics of a hemilabile ligand through secondary Lewis acid/base and/or cation-dipole interactions. To enforce such interactions, catalysts sitting at the interface of organometallic catalysis and supramolecular chemistry were designed. A macrocyclic crown ether was incorporated into a robust organometallic pincer ligand, and these "pincer-crown ether" ligands have been explored in catalysis. Complementary studies of controlled catalysis and detailed mechanistic analysis guided the development of iridium, nickel, and palladium pincer-crown ether catalysts capable of substrate gating. Toggling the gate between open and closed states leads to switchable catalysis, where cation addition/removal changes the turnover frequency or the product selectivity. Varying the degree of gating leads to tunable catalysis, where the activity can be tuned based on the identity and amount of salt added. Research has focused on reactions of alkenes, particularly isomerization reactions, which has in turn led to design principles for cation-controlled catalysts.
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Affiliation(s)
- Sebastian Acosta-Calle
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Alexander J M Miller
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
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5
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Malakar S, Gordon BM, Mandal S, Emge TJ, Goldman AS. Ruthenium Complexes of a Triphosphorus-Coordinating Pincer Ligand: Ru-P Ligand-Substituent Exchange Reactions Driven by Large Variations of Bond Energies. Inorg Chem 2023; 62:4525-4532. [PMID: 36881741 DOI: 10.1021/acs.inorgchem.2c04416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
Abstract
The reaction of [(p-cymene)RuCl2]2 with the triphosphine ligand bis(2-di-tert-butylphosphinophenyl)phosphine (tBuPHPP) results in an unusual exchange reaction in which a chloride ligand and a phosphorus-bound H atom are exchanged ("H-P/Ru-Cl exchange") to give the (chlorophosphine)ruthenium hydride complex (tBuPClPP)RuHCl [1Cl-HCl; tBuPClPP = bis(2-di-tert-butylphosphinophenyl)chlorophosphine]. Density functional theory calculations indicate that the presumed initial product of metalation, (tBuPHPP)RuCl2 (1H-Cl2), undergoes an H-P/Ru-Cl exchange via sequential P-to-Ru α-H migration to give the intermediate (tBuPPP)RuHCl2, followed by Ru-to-P α-Cl migration to give the observed product 1Cl-HCl (crystallographically characterized). Dehydrochlorination of 1Cl-HCl under a H2 atmosphere gives (tBuPClPP)RuH4 (1Cl-H4), which then can undergo a second dehydrochlorination and addition of H2 to give (tBuPHPP)RuH4 (1H-H4). This reaction may proceed via the reverse of the intramolecular exchange by 1H-Cl2, i.e., loss of H2 from 1Cl-H4 to give 1Cl-H2, which could undergo Cl-P/Ru-H exchange to give (tBuPHPP)RuHCl (1H-HCl). Accordingly, the thermodynamics of Cl-P/Ru-H exchange are found to be highly dependent on the nature of the ancillary anionic ligand (H or Cl), which is not directly involved in the exchange. The origin of this thermodynamic dependence can be explained in terms of the high stability of complexes (RPXPP)RuHCl (X = H, Cl; R = Me, tBu), in which the hydride is approximately trans to a vacant coordination site and the central phosphine group is approximately trans to the weak-trans-influence chloride ligand. This conclusion has general implications for five-coordinate d6 complexes, both pincer- and nonpincer-ligated.
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Affiliation(s)
- Santanu Malakar
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
| | - Benjamin M Gordon
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
| | - Souvik Mandal
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
| | - Thomas J Emge
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
| | - Alan S Goldman
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States
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6
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De Leon E, Gonzalez F, Bauskar P, Gonzalez-Eymard S, De Los Santos D, Shoshani MM. Amplifying Reactivity of Metal Hydrides: A Heterotrimetallic NiAl 2(μ 2-H) 2 Catalyst for the Dearomatization of N-Heterocycles. Organometallics 2023. [DOI: 10.1021/acs.organomet.2c00668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Affiliation(s)
- Edgardo De Leon
- Department of Chemistry, University of Texas Rio Grande Valley, 1 W. University Blvd. Brownsville, Texas 78520, United States
| | - Fernando Gonzalez
- Department of Chemistry, University of Texas Rio Grande Valley, 1 W. University Blvd. Brownsville, Texas 78520, United States
| | - Preetika Bauskar
- Department of Chemistry, University of Texas Rio Grande Valley, 1 W. University Blvd. Brownsville, Texas 78520, United States
| | - Sergio Gonzalez-Eymard
- Department of Chemistry, University of Texas Rio Grande Valley, 1 W. University Blvd. Brownsville, Texas 78520, United States
| | - David De Los Santos
- Department of Chemistry, University of Texas Rio Grande Valley, 1 W. University Blvd. Brownsville, Texas 78520, United States
| | - Manar M. Shoshani
- Department of Chemistry, University of Texas Rio Grande Valley, 1 W. University Blvd. Brownsville, Texas 78520, United States
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7
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Chemical Transformations in Heterobimetallic Complexes Facilitated by the Second Coordination Sphere. TOP ORGANOMETAL CHEM 2023. [DOI: 10.1007/3418_2022_79] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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8
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Kim S, Lee DH, Park KM, Jung JH, Lee SS, Park IH. Unexpected Solvent-Dependent Self-Assembly of Alkali Metal Complexes of Calix[6]- mono-crown-4: Dinuclear Bowls, a Pseudo-Capsule, and a One-Dimensional Polymer. Inorg Chem 2022; 61:18213-18220. [DOI: 10.1021/acs.inorgchem.2c03020] [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)
- Seulgi Kim
- Department of Chemistry and Research Institute of Natural Sciences, Gyeongsang National University, Jinju 52828, South Korea
| | - Dong Hee Lee
- Graduate School of Analytical Science and Technology (GRAST), Chungnam National University, Daejeon 34134, South Korea
| | - Ki-Min Park
- Department of Chemistry and Research Institute of Natural Sciences, Gyeongsang National University, Jinju 52828, South Korea
| | - Jong Hwa Jung
- Department of Chemistry and Research Institute of Natural Sciences, Gyeongsang National University, Jinju 52828, South Korea
| | - Shim Sung Lee
- Department of Chemistry and Research Institute of Natural Sciences, Gyeongsang National University, Jinju 52828, South Korea
| | - In-Hyeok Park
- Graduate School of Analytical Science and Technology (GRAST), Chungnam National University, Daejeon 34134, South Korea
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9
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Tran TV, Lee E, Nguyen YH, Nguyen HD, Do LH. Customizing Polymers by Controlling Cation Switching Dynamics in Non-Living Polymerization. J Am Chem Soc 2022; 144:17129-17139. [PMID: 36069706 DOI: 10.1021/jacs.2c07098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Controlling the chain growth process in non-living polymerization reactions is difficult because chain termination typically occurs faster than the time it takes to apply an external trigger. To overcome this limitation, we have developed a strategy to regulate non-living polymerizations by exploiting the chemical equilibria between a metal catalyst and secondary metal cations. We have prepared two nickel phenoxyphosphine-polyethylene glycol variants, one with 2-methoxyphenyl (Ni1) and another with 2,6-dimethoxyphenyl (Ni2) phosphine substituents. Ethylene polymerization studies using these complexes in the presence of alkali salts revealed that chain growth is strongly dependent on electronic effects, whereas chain termination is dependent on both steric and electronic effects. By adjusting the solvent polarity, we can favor polymerizations via non-switching or dynamic switching modes. For example, in a 100:0.2 mixture of toluene/diethyl ether, reactions of Ni1 and both Li+ and Na+ cations in the presence of ethylene yielded bimodal polymers with different relative fractions depending on the Li+/Na+ ratio used. In a 98:2 mixture of toluene/diethyl ether, reactions of Ni2 and Cs+ in the presence of ethylene generated monomodal polyethylene with dispersity <2.0 and increasing molecular weight as the amount of Cs+ added increased. Solution studies by NMR spectroscopy showed that cation exchange between the nickel complexes and alkali cations in 98:2 toluene/diethyl ether is fast on the NMR time scale, which supports our proposed dynamic switching mechanism.
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Affiliation(s)
- Thi V Tran
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
| | - Eryn Lee
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
| | - Yennie H Nguyen
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
| | - Hieu D Nguyen
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
| | - Loi H Do
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
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10
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Golwankar RR, Kumar A, Day VW, Blakemore JD. Revealing the Influence of Diverse Secondary Metal Cations on Redox‐Active Palladium Complexes. Chemistry 2022; 28:e202200344. [DOI: 10.1002/chem.202200344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Indexed: 11/09/2022]
Affiliation(s)
- Riddhi R. Golwankar
- Department of Chemistry University of Kansas 1567 Irving Hill Road Lawrence Kansas 66045 USA
| | - Amit Kumar
- Department of Chemistry University of Kansas 1567 Irving Hill Road Lawrence Kansas 66045 USA
- Current address: Department of Chemistry University of Pennsylvania Philadelphia Pennsylvania 19104 USA
| | - Victor W. Day
- Department of Chemistry University of Kansas 1567 Irving Hill Road Lawrence Kansas 66045 USA
| | - James D. Blakemore
- Department of Chemistry University of Kansas 1567 Irving Hill Road Lawrence Kansas 66045 USA
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11
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Kikuchi K, Sumida A, Imoto H, Naka K. Phosphorescent Metallacrown Ethers Enchained Through Coordination of Arsafluorene to Platinum(II) Dihalide. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100799] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Kazuma Kikuchi
- Faculty of Molecular Chemistry and Engineering, Graduate School of Science and Technology Kyoto Institute of Technology Goshokaido-cho, Matsugasaki, Sakyo-ku Kyoto 606-8585 Japan
| | - Akifumi Sumida
- Faculty of Molecular Chemistry and Engineering, Graduate School of Science and Technology Kyoto Institute of Technology Goshokaido-cho, Matsugasaki, Sakyo-ku Kyoto 606-8585 Japan
| | - Hiroaki Imoto
- Faculty of Molecular Chemistry and Engineering, Graduate School of Science and Technology Kyoto Institute of Technology Goshokaido-cho, Matsugasaki, Sakyo-ku Kyoto 606-8585 Japan
| | - Kensuke Naka
- Faculty of Molecular Chemistry and Engineering, Graduate School of Science and Technology Kyoto Institute of Technology Goshokaido-cho, Matsugasaki, Sakyo-ku Kyoto 606-8585 Japan
- Materials Innovation Lab, Kyoto Institute of Technology Goshokaido-cho, Matsugasaki, Sakyo-ku Kyoto 606-8585 Japan
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12
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Shanahan JP, Moore CM, Kampf JW, Szymczak NK. Modulation of H +/H - exchange in iridium-hydride 2-hydroxypyridine complexes by remote Lewis acids. Chem Commun (Camb) 2021; 57:11705-11708. [PMID: 34693408 DOI: 10.1039/d1cc04778g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A series of iridium hydride complexes featuring dihydrogen bonding are presented and shown to undergo rapid H+/H- exchange (1240 s-1 at 25 °C). We demonstrate that the H+/H- exchange rate can be modified by post-synthetic modification at a remote site using BH3, Zn(C6F5)2, and [Me3O][BF4]. This route provides a complementary strategy to traditional methods that rely on pre-metalation modifications to a metal's primary sphere.
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Affiliation(s)
- J P Shanahan
- Department of Chemistry, Columbia University, New York, New York 10027, USA
| | - C M Moore
- Chemistry Division, Los Alamos National Laboratory, MS K558, Los Alamos, NM 87545, USA
| | - Jeff W Kampf
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, MI 48109-1055, USA.
| | - N K Szymczak
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, MI 48109-1055, USA.
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13
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Kelsey SR, Kumar A, Oliver AG, Day VW, Blakemore JD. Promotion and Tuning of the Electrochemical Reduction of Hetero‐ and Homobimetallic Zinc Complexes**. ChemElectroChem 2021. [DOI: 10.1002/celc.202100358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Shaun R. Kelsey
- Department of Chemistry University of Kansas 1567 Irving Hill Rd Lawrence KS 66045
| | - Amit Kumar
- Department of Chemistry University of Kansas 1567 Irving Hill Rd Lawrence KS 66045
| | - Allen G. Oliver
- Department of Chemistry and Biochemistry University of Notre Dame 149 Stepan Chemistry Notre Dame IN 46556 USA
| | - Victor W. Day
- Department of Chemistry University of Kansas 1567 Irving Hill Rd Lawrence KS 66045
| | - James D. Blakemore
- Department of Chemistry University of Kansas 1567 Irving Hill Rd Lawrence KS 66045
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14
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Nakamura K, Kondo M, Krishnan CG, Takizawa S, Sasai H. Azopyridine-based chiral oxazolines with rare-earth metals for photoswitchable catalysis. Chem Commun (Camb) 2021; 57:7414-7417. [PMID: 34231579 DOI: 10.1039/d1cc02602j] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An azopyridine-based oxazoline was developed for utilizing azo group coordination and isomerization as a photoswitchable ligand. The ligand coordinated to rare-earth metal (RE) catalyst underwent efficient E/Z photoisomerization, suggesting tri- and bidentate coordination switching. The photoisomerization of the ligand enabled modulation of the enantioselectivity of an RE-catalyzed aminal forming reaction.
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Affiliation(s)
- Kento Nakamura
- SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
| | - Masaru Kondo
- SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Mihogaoka, Ibaraki, Osaka 567-0047, Japan. and Department of Materials Science and Engineering, Graduate School of Science and Engineering, Ibaraki University, Hitachi 316-8511, Ibaraki, Japan
| | - Chandu G Krishnan
- SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
| | - Shinobu Takizawa
- SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
| | - Hiroaki Sasai
- SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
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15
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Durran SE, Elsegood MRJ, Noble TA, Smith MB, Gelbrich T, Hursthouse MB, Light ME. Synthesis and Characterisation of Transition Metal Complexes of a Novel 1,5‐benzodiazepine‐Functionalised Tertiary Phosphine. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100236] [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)
- Sean E. Durran
- Department of Chemistry Loughborough University Loughborough LE11 3TU UK
| | | | - Thomas A. Noble
- Department of Chemistry Loughborough University Loughborough LE11 3TU UK
| | - Martin B. Smith
- Department of Chemistry Loughborough University Loughborough LE11 3TU UK
| | - Thomas Gelbrich
- UK National Crystallography Service School of Chemistry University of Southampton Highfield Southampton S017 1BJ UK
| | - Michael B. Hursthouse
- UK National Crystallography Service School of Chemistry University of Southampton Highfield Southampton S017 1BJ UK
| | - Mark E. Light
- UK National Crystallography Service School of Chemistry University of Southampton Highfield Southampton S017 1BJ UK
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16
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17
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Charles RM, Brewster TP. H 2 and carbon-heteroatom bond activation mediated by polarized heterobimetallic complexes. Coord Chem Rev 2021; 433. [PMID: 35418712 DOI: 10.1016/j.ccr.2020.213765] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The field of heterobimetallic chemistry has rapidly expanded over the last decade. In addition to their interesting structural features, heterobimetallic structures have been found to facilitate a range of stoichiometric bond activations and catalytic processes. The accompanying review summarizes advances in this area since January of 2010. The review encompasses well-characterized heterobimetallic complexes, with a particular focus on mechanistic details surrounding their reactivity applications.
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Affiliation(s)
- R Malcolm Charles
- Department of Chemistry, The University of Memphis, 3744 Walker Ave., Smith Chemistry Building, Memphis, TN 38152, United States
| | - Timothy P Brewster
- Department of Chemistry, The University of Memphis, 3744 Walker Ave., Smith Chemistry Building, Memphis, TN 38152, United States
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18
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Sumida A, Kobayashi R, Yumura T, Imoto H, Naka K. Dibenzoarsacrowns: an experimental and computational study on the coordination behaviors. Chem Commun (Camb) 2021; 57:2013-2016. [PMID: 33416057 DOI: 10.1039/d0cc07191a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Dibenzoarsacrowns have been synthesized as a novel class of heteroatom-fused crown ethers. The dibenzoarsacrowns can size-selectively capture alkali metal cations, and the arsenic atoms chemoselectively coordinated to gold(i) chloride (AuCl) due to the soft Lewis acid-base interaction. It is notable that the AuCl complex of 21-dibenzoarsacrown-7 further encapsulated Na+ with the enhanced association constant from bare 21-dibenzoarsacrown-7. The positive allosteric effect was studied computationally.
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Affiliation(s)
- Akifumi Sumida
- Faculty of Molecular Chemistry and Engineering, Kyoto Institute of Technology, Goshokaido-cho, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan.
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19
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Camp AM, Kita MR, Blackburn PT, Dodge HM, Chen CH, Miller AJM. Selecting Double Bond Positions with a Single Cation-Responsive Iridium Olefin Isomerization Catalyst. J Am Chem Soc 2021; 143:2792-2800. [DOI: 10.1021/jacs.0c11601] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andrew M. Camp
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599−3290, United States
| | - Matthew R. Kita
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599−3290, United States
| | - P. Thomas Blackburn
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599−3290, United States
| | - Henry M. Dodge
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599−3290, United States
| | - Chun-Hsing Chen
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599−3290, United States
| | - Alexander J. M. Miller
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599−3290, United States
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20
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Dodge HM, Kita MR, Chen CH, Miller AJM. Identifying and Evading Olefin Isomerization Catalyst Deactivation Pathways Resulting from Ion-Tunable Hemilability. ACS Catal 2020. [DOI: 10.1021/acscatal.0c03784] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Henry M. Dodge
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Matthew R. Kita
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Chun-Hsing Chen
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Alexander J. M. Miller
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
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21
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Yoo C, Dodge HM, Farquhar AH, Gardner KE, Miller AJM. Decarbonylative ether dissection by iridium pincer complexes. Chem Sci 2020; 11:12130-12138. [PMID: 34123222 PMCID: PMC8162749 DOI: 10.1039/d0sc03736b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 09/24/2020] [Indexed: 11/21/2022] Open
Abstract
A unique chain-rupturing transformation that converts an ether functionality into two hydrocarbyl units and carbon monoxide is reported, mediated by iridium(i) complexes supported by aminophenylphosphinite (NCOP) pincer ligands. The decarbonylation, which involves the cleavage of one C-C bond, one C-O bond, and two C-H bonds, along with formation of two new C-H bonds, was serendipitously discovered upon dehydrochlorination of an iridium(iii) complex containing an aza-18-crown-6 ether macrocycle. Intramolecular cleavage of macrocyclic and acyclic ethers was also found in analogous complexes featuring aza-15-crown-5 ether or bis(2-methoxyethyl)amino groups. Intermolecular decarbonylation of cyclic and linear ethers was observed when diethylaminophenylphosphinite iridium(i) dinitrogen or norbornene complexes were employed. Mechanistic studies reveal the nature of key intermediates along a pathway involving initial iridium(i)-mediated double C-H bond activation.
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Affiliation(s)
- Changho Yoo
- Department of Chemistry, University of North Carolina at Chapel Hill Chapel Hill North Carolina 27599-3290 USA
| | - Henry M Dodge
- Department of Chemistry, University of North Carolina at Chapel Hill Chapel Hill North Carolina 27599-3290 USA
| | - Alexandra H Farquhar
- Department of Chemistry, University of North Carolina at Chapel Hill Chapel Hill North Carolina 27599-3290 USA
| | - Kristen E Gardner
- Department of Chemistry, University of North Carolina at Chapel Hill Chapel Hill North Carolina 27599-3290 USA
| | - Alexander J M Miller
- Department of Chemistry, University of North Carolina at Chapel Hill Chapel Hill North Carolina 27599-3290 USA
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22
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Suzuki S, Ishida Y, Kameo H, Sakaki S, Kawaguchi H. Counterion Dependence of Dinitrogen Activation and Functionalization by a Diniobium Hydride Anion. Angew Chem Int Ed Engl 2020; 59:13444-13450. [PMID: 32352196 DOI: 10.1002/anie.202006039] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Indexed: 01/10/2023]
Abstract
We report the synthesis of anionic diniobium hydride complexes with a series of alkali metal cations (Li+ , Na+ , and K+ ) and the counterion dependence of their reactivity with N2 . Exposure of these complexes to N2 initially produces the corresponding side-on end-on N2 complexes, the fate of which depends on the nature of countercations. The lithium derivative undergoes stepwise migratory insertion of the hydride ligands onto the aryloxide units, yielding the end-on bridging N2 complex. For the potassium derivative, the N-N bond cleavage takes place along with H2 elimination to form the nitride complex. Treatment of the side-on end-on N2 complex with Me3 SiCl results in silylation of the terminal N atom and subsequent N-N bond cleavage along with H2 elimination, giving the nitride-imide-bridged diniobium complex.
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Affiliation(s)
- Shoi Suzuki
- Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Yutaka Ishida
- Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
| | - Hajime Kameo
- Department of Chemistry, Graduate School of Science, Osaka Prefecture University, Gakuen-cho 1-1, Naka-ku, 599-8531, Sakai, Osaka, Japan
| | - Shigeyoshi Sakaki
- Fukui Institute for Fundamental Chemistry, Kyoto University, Takano-nishihiraki-cho 34-4, Sakyo-ku, Kyoto, 606-8103, Japan
| | - Hiroyuki Kawaguchi
- Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, 152-8551, Japan
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23
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Suzuki S, Ishida Y, Kameo H, Sakaki S, Kawaguchi H. Counterion Dependence of Dinitrogen Activation and Functionalization by a Diniobium Hydride Anion. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202006039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Shoi Suzuki
- Department of Chemistry Tokyo Institute of Technology Ookayama, Meguro-ku Tokyo 152-8551 Japan
| | - Yutaka Ishida
- Department of Chemistry Tokyo Institute of Technology Ookayama, Meguro-ku Tokyo 152-8551 Japan
| | - Hajime Kameo
- Department of Chemistry Graduate School of Science Osaka Prefecture University Gakuen-cho 1-1, Naka-ku 599-8531 Sakai Osaka Japan
| | - Shigeyoshi Sakaki
- Fukui Institute for Fundamental Chemistry Kyoto University Takano-nishihiraki-cho 34-4, Sakyo-ku Kyoto 606-8103 Japan
| | - Hiroyuki Kawaguchi
- Department of Chemistry Tokyo Institute of Technology Ookayama, Meguro-ku Tokyo 152-8551 Japan
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24
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Mondol R, Otten E. Cation effects on dynamics of ligand-benzylated formazanate boron and aluminium complexes. Dalton Trans 2020; 49:9094-9098. [PMID: 32573637 DOI: 10.1039/d0dt01918f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The dynamic processes present in ligand-benzylated formazanate boron and aluminium complexes are investigated using variable temperature NMR experiments and lineshape analyses. The observed difference in activation parameters for complexes containing either organic countercations (NBu4+) or alkali cations is rationalized on the basis of a different degree of ion-pairing in the ground state, and the data are in all cases consistent with a mechanism that involves pyramidal inversion at the nitrogens in the heterocyclic ring rather than homolytic N-C(benzyl) bond cleavage.
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Affiliation(s)
- Ranajit Mondol
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
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25
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26
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Baumgardner DF, Parks WE, Gilbertson JD. Harnessing the active site triad: merging hemilability, proton responsivity, and ligand-based redox-activity. Dalton Trans 2020; 49:960-965. [PMID: 31907502 PMCID: PMC7386000 DOI: 10.1039/c9dt04470a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Metalloenzymes catalyze many important reactions by managing the proton and electron flux at the enzyme active site. The motifs utilized to facilitate these transformations include hemilabile, redox-active, and so called proton responsive sites. Given the importance of incorporating and understanding these motifs in the area of coordination chemistry and catalysis, we highlight recent milestones in the field. Work incorporating the triad of hemilability, redox-activity, and proton responsivity into single ligand scaffolds will be described.
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Affiliation(s)
- Douglas F Baumgardner
- Department of Chemistry, Western Washington University, Bellingham, Washington 98225, USA.
| | - Wyatt E Parks
- Department of Chemistry, Western Washington University, Bellingham, Washington 98225, USA.
| | - John D Gilbertson
- Department of Chemistry, Western Washington University, Bellingham, Washington 98225, USA.
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27
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Shahsavari HR, Babadi Aghakhanpour R, Biglari A, Niazi M, Mastrorilli P, Todisco S, Gallo V, Lalinde E, Moreno MT, Giménez N, Halvagar MR. C(sp 2)–C(sp 2) Reductive Elimination from a Diarylplatinum(II) Complex Induced by a S–S Bond Oxidative Addition at Room Temperature. Organometallics 2020. [DOI: 10.1021/acs.organomet.9b00771] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hamid R. Shahsavari
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Reza Babadi Aghakhanpour
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Abbas Biglari
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Maryam Niazi
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | | | | | - Vito Gallo
- DICATECh, Politecnico di Bari, I-70125 Bari, Italy
| | - Elena Lalinde
- Departamento de Química-Centro de Síntesis Química de La Rioja (CISQ), Universidad de La Rioja, 26006 Logroño, Spain
| | - M. Teresa Moreno
- Departamento de Química-Centro de Síntesis Química de La Rioja (CISQ), Universidad de La Rioja, 26006 Logroño, Spain
| | - Nora Giménez
- Departamento de Química-Centro de Síntesis Química de La Rioja (CISQ), Universidad de La Rioja, 26006 Logroño, Spain
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28
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Cooperative Reactivity by Pincer-Type Complexes Possessing Secondary Coordination Sphere. TOP ORGANOMETAL CHEM 2020. [DOI: 10.1007/3418_2020_65] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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29
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Recent advances in the chemistry of group 9—Pincer organometallics. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2020. [DOI: 10.1016/bs.adomc.2019.09.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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30
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Singh A, Gelman D. Cooperative Reactivity in Carbometalated Pincer-Type Complexes Possessing an Appended Functionality. ACS Catal 2019. [DOI: 10.1021/acscatal.9b04882] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Ajeet Singh
- Institute of Chemistry, The Hebrew University, Edmund Safra Campus, 91904 Jerusalem, Israel
| | - Dmitri Gelman
- Institute of Chemistry, The Hebrew University, Edmund Safra Campus, 91904 Jerusalem, Israel
- Peoples’ Friendship University of Russia (RUDN University), Miklukho-Maklay St., 6, 117198 Moscow, Russia
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31
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Smith JB, Camp AM, Farquhar AH, Kerr SH, Chen CH, Miller AJM. Organometallic Elaboration as a Strategy for Tuning the Supramolecular Characteristics of Aza-Crown Ethers. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00462] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Jacob B. Smith
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Andrew M. Camp
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Alexandra H. Farquhar
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Stewart H. Kerr
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Chun-Hsing Chen
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Alexander J. M. Miller
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
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32
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Lai A, Hern ZC, Diaconescu PL. Switchable Ring‐Opening Polymerization by a Ferrocene Supported Aluminum Complex. ChemCatChem 2019. [DOI: 10.1002/cctc.201900747] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Amy Lai
- Department of Chemistry and Biochemistry University of California, Los Angeles 607 Charles E. Young Drive East Los Angeles CA 90095 USA
| | - Zachary C. Hern
- Department of Chemistry and Biochemistry University of California, Los Angeles 607 Charles E. Young Drive East Los Angeles CA 90095 USA
| | - Paula L. Diaconescu
- Department of Chemistry and Biochemistry University of California, Los Angeles 607 Charles E. Young Drive East Los Angeles CA 90095 USA
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33
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Jackson BJ, Najera DC, Matson EM, Woods TJ, Bertke JA, Fout AR. Synthesis and Characterization of (DIPPCCC)Fe Complexes: A Zwitterionic Metalation Method and CO2 Reactivity. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00271] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Bailey J. Jackson
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Daniel C. Najera
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Ellen M. Matson
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Toby J. Woods
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Jeffery A. Bertke
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
| | - Alison R. Fout
- School of Chemical Sciences, University of Illinois at Urbana—Champaign, 600 South Matthews Avenue, Urbana, Illinois 61801, United States
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34
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Cai Z, Xiao D, Do LH. Cooperative Heterobimetallic Catalysts in Coordination Insertion Polymerization. COMMENT INORG CHEM 2019. [DOI: 10.1080/02603594.2019.1570165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Zhongzheng Cai
- Department of Chemistry, University of Houston, Houston, Texas, USA
| | - Dawei Xiao
- Department of Chemistry, University of Houston, Houston, Texas, USA
| | - Loi H. Do
- Department of Chemistry, University of Houston, Houston, Texas, USA
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35
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Martínez-Martínez AJ, Weller AS. Solvent-free anhydrous Li+, Na+ and K+ salts of [B(3,5-(CF3)2C6H3)4]−, [BArF4]−. Improved synthesis and solid-state structures. Dalton Trans 2019; 48:3551-3554. [DOI: 10.1039/c9dt00235a] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report an alternative, improved, multigram scale (∼20 g, 60–70% yield) preparation of solvent-free anhydrous Li[BArF4], Na[BArF4] and K[BArF4], and the corresponding single-crystal X-ray characterisation of [Li(H2O)][BArF4], Na[BArF4]˙ and K[BArF4].
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Affiliation(s)
| | - Andrew S. Weller
- Department of Chemistry
- Chemistry Research Laboratories
- Mansfield Road
- University of Oxford
- Oxford
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36
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Yoo C, Dodge HM, Miller AJM. Cation-controlled catalysis with crown ether-containing transition metal complexes. Chem Commun (Camb) 2019; 55:5047-5059. [DOI: 10.1039/c9cc00803a] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This Feature Article reviews the structural motifs and catalytic applications of crown ether-containing catalysts and details the development of “pincer-crown ether” ligands for applications in controlled catalysis.
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Affiliation(s)
- Changho Yoo
- Department of Chemistry
- University of North Carolina at Chapel Hill
- Chapel Hill
- USA
| | - Henry M. Dodge
- Department of Chemistry
- University of North Carolina at Chapel Hill
- Chapel Hill
- USA
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37
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Xiao D, Cai Z, Do LH. Accelerating ethylene polymerization using secondary metal ions in tetrahydrofuran. Dalton Trans 2019; 48:17887-17897. [DOI: 10.1039/c9dt04288a] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A variety of metal cations are capable of enhancing the ethylene polymerization rates of nickel phosphine phosphonate-polyethylene glycol catalysts.
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Affiliation(s)
- Dawei Xiao
- Department of Chemistry
- University of Houston
- Houston
- USA
| | | | - Loi H. Do
- Department of Chemistry
- University of Houston
- Houston
- USA
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38
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Vishwakarma NK, Hwang YH, Adiyala PR, Kim DP. Flow-Assisted Switchable Catalysis of Metal Ions in a Microenvelope System Embedded with Core-Shell Polymers. ACS APPLIED MATERIALS & INTERFACES 2018; 10:43104-43111. [PMID: 30444347 DOI: 10.1021/acsami.8b17926] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Many efforts have been made on stimuli-responsive switchable catalysis to trigger catalytic activity over various chemical reactions. However, the reported light-, pH- or chemically responsive organocatalysts are mostly incomplete in the aspects of shielding efficiency and long-term performance. Here, we advance the flow-assisted switchable catalysis of metal ions in a microenvelope system that allows the on-off catalysis mode on demand for long-lasting catalytic activity. Various metal-ion catalysts can be selectively embedded in a novel polymeric core-shell of the heteroarm star copolymer of poly(styrene) and poly(4-vinylpyridine) emanated from a polyhedral oligomeric silsesquioxane center. The immobilized core-shell polymer on the inner wall of a poly(dimethylsiloxane) envelope microreactor shows on-off switching catalysis between the expanded active mode and contracted protective mode under continuous flow of solvents or subsequent dry conditions. In particular, the preserved catalytic activity of toxic Hg2+ for oxymercuration was demonstrated even for 2 weeks without leaching, whereas the activity of moisture-sensitive Ru3+ ions for polymerization of methyl methacrylate was maintained even after 5 days from an open atmosphere. It is practical that the tight environment of the enveloped microfluidic system facilitates cyclic switching between the reaction-"on" and -"off" modes of such toxic, sensitive/expensive catalysts for long-term prevention and preservation.
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Affiliation(s)
- Niraj K Vishwakarma
- National Creative Research Center for Intelligent Microprocess of Pharmaceutical Synthesis, Department of Chemical Engineering , Pohang University of Science and Technology (POSTECH) , Pohang 37673 , Korea
| | - Yoon-Ho Hwang
- National Creative Research Center for Intelligent Microprocess of Pharmaceutical Synthesis, Department of Chemical Engineering , Pohang University of Science and Technology (POSTECH) , Pohang 37673 , Korea
| | - Praveen Reddy Adiyala
- National Creative Research Center for Intelligent Microprocess of Pharmaceutical Synthesis, Department of Chemical Engineering , Pohang University of Science and Technology (POSTECH) , Pohang 37673 , Korea
| | - Dong-Pyo Kim
- National Creative Research Center for Intelligent Microprocess of Pharmaceutical Synthesis, Department of Chemical Engineering , Pohang University of Science and Technology (POSTECH) , Pohang 37673 , Korea
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39
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Chantarojsiri T, Reath AH, Yang JY. Cationic Charges Leading to an Inverse Free‐Energy Relationship for N−N Bond Formation by Mn
VI
Nitrides. Angew Chem Int Ed Engl 2018; 57:14037-14042. [DOI: 10.1002/anie.201805832] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 07/15/2018] [Indexed: 11/12/2022]
Affiliation(s)
- Teera Chantarojsiri
- Department of Chemistry University of California Irvine CA USA
- Department of Chemistry Faculty of Science Mahidol University Bangkok Thailand
| | | | - Jenny Y. Yang
- Department of Chemistry University of California Irvine CA USA
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40
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Chantarojsiri T, Reath AH, Yang JY. Cationic Charges Leading to an Inverse Free‐Energy Relationship for N−N Bond Formation by Mn
VI
Nitrides. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201805832] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Teera Chantarojsiri
- Department of Chemistry University of California Irvine CA USA
- Department of Chemistry Faculty of Science Mahidol University Bangkok Thailand
| | | | - Jenny Y. Yang
- Department of Chemistry University of California Irvine CA USA
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41
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Riddlestone IM, Kraft A, Schaefer J, Krossing I. Die Schöne (WCA) und das (kationische) Biest: Neues aus der Chemie von und mit schwach koordinierenden Anionen. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201710782] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Ian M. Riddlestone
- Institut für Anorganische und Analytische Chemie; Freiburger Materialforschungszentrum (FMF); Universität Freiburg; Albertstraße 21 79104 Freiburg Deutschland
| | - Anne Kraft
- Institut für Anorganische und Analytische Chemie; Freiburger Materialforschungszentrum (FMF); Universität Freiburg; Albertstraße 21 79104 Freiburg Deutschland
| | - Julia Schaefer
- Institut für Anorganische und Analytische Chemie; Freiburger Materialforschungszentrum (FMF); Universität Freiburg; Albertstraße 21 79104 Freiburg Deutschland
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie; Freiburger Materialforschungszentrum (FMF); Universität Freiburg; Albertstraße 21 79104 Freiburg Deutschland
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42
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Riddlestone IM, Kraft A, Schaefer J, Krossing I. Taming the Cationic Beast: Novel Developments in the Synthesis and Application of Weakly Coordinating Anions. Angew Chem Int Ed Engl 2018; 57:13982-14024. [PMID: 29266644 DOI: 10.1002/anie.201710782] [Citation(s) in RCA: 234] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Indexed: 12/11/2022]
Abstract
This Review gives a comprehensive overview of the most topical weakly coordinating anions (WCAs) and contains information on WCA design, stability, and applications. As an update to the 2004 review, developments in common classes of WCA are included. Methods for the incorporation of WCAs into a given system are discussed and advice given on how to best choose a method for the introduction of a particular WCA. A series of starting materials for a large number of WCA precursors and references are tabulated as a useful resource when looking for procedures to prepare WCAs. Furthermore, a collection of scales that allow the performance of a WCA, or its underlying Lewis acid, to be judged is collated with some advice on how to use them. The examples chosen to illustrate WCA developments are taken from a broad selection of topics where WCAs play a role. In addition a section focusing on transition metal and catalysis applications as well as supporting electrolytes is also included.
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Affiliation(s)
- Ian M Riddlestone
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Anne Kraft
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Julia Schaefer
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Ingo Krossing
- Institut für Anorganische und Analytische Chemie and Freiburger Materialforschungszentrum (FMF), Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
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43
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Burns KT, Marks WR, Cheung PM, Seda T, Zakharov LN, Gilbertson JD. Uncoupled Redox-Inactive Lewis Acids in the Secondary Coordination Sphere Entice Ligand-Based Nitrite Reduction. Inorg Chem 2018; 57:9601-9610. [PMID: 29608297 PMCID: PMC6102076 DOI: 10.1021/acs.inorgchem.8b00032] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Metal complexes composed of redox-active pyridinediimine (PDI) ligands are capable of forming ligand-centered radicals. In this Forum article, we demonstrate that integration of these types of redox-active sites with bioinspired secondary coordination sphere motifs produce direduced complexes, where the reduction potential of the ligand-based redox sites is uncoupled from the secondary coordination sphere. The utility of such ligand design was explored by encapsulating redox-inactive Lewis acidic cations via installation of a pendant benzo-15-crown-5 in the secondary coordination sphere of a series of Fe(PDI) complexes. Fe(15bz5PDI)(CO)2 was shown to encapsulate the redox-inactive alkali ion, Na+, causing only modest (31 mV) anodic shifts in the ligand-based redox-active sites. By uncoupling the Lewis acidic sites from the ligand-based redox sites, the pendant redox-inactive ion, Na+, can entice the corresponding counterion, NO2-, for reduction to NO. The subsequent initial rate analysis reveals an acceleration in anion reduction, confirming this hypothesis.
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Affiliation(s)
- Kyle T. Burns
- Department of Chemistry, Western Washington University, Bellingham, Washington 98225, United States
| | - Walker R. Marks
- Department of Chemistry, Western Washington University, Bellingham, Washington 98225, United States
| | - Pui Man Cheung
- Department of Chemistry, Western Washington University, Bellingham, Washington 98225, United States
| | - Takele Seda
- Department of Physics, Western Washington University, Bellingham, Washington 98225, United States
| | - Lev N. Zakharov
- Department of Chemistry, University of Oregon, Eugene, Oregon 97403, United States
| | - John D. Gilbertson
- Department of Chemistry, Western Washington University, Bellingham, Washington 98225, United States
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44
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Broere DLJ, Mercado BQ, Bill E, Lancaster KM, Sproules S, Holland PL. Alkali Cation Effects on Redox-Active Formazanate Ligands in Iron Chemistry. Inorg Chem 2018; 57:9580-9591. [PMID: 29629752 PMCID: PMC6116910 DOI: 10.1021/acs.inorgchem.8b00226] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Noncovalent interactions of organic moieties with Lewis acidic alkali cations can greatly affect structure and reactivity. Herein, we describe the effects of interactions with alkali-metal cations within a series of reduced iron complexes bearing a redox-active formazanate ligand, in terms of structures, magnetism, spectroscopy, and reaction rates. In the absence of a crown ether to sequester the alkali cation, dimeric complexes are isolated wherein the formazanate has rearranged to form a five-membered metallacycle. The dissociation of these dimers is dependent on the binding mode and size of the alkali cation. In the dimers, the formazanate ligands are radical dianions, as shown by X-ray absorption spectroscopy, Mössbauer spectroscopy, and analysis of metrical parameters. These experimental measures are complemented by density functional theory calculations that show the spin density on the bridging ligands.
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Affiliation(s)
- Daniel L J Broere
- Department of Chemistry , Yale University , New Haven , Connecticut 06520 , United States
| | - Brandon Q Mercado
- Department of Chemistry , Yale University , New Haven , Connecticut 06520 , United States
| | - Eckhard Bill
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36 , D-45470 Mülheim an der Ruhr , Germany
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Stephen Sproules
- WestCHEM, School of Chemistry , University of Glasgow , Glasgow G12 8QQ , United Kingdom
| | - Patrick L Holland
- Department of Chemistry , Yale University , New Haven , Connecticut 06520 , United States
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45
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Dorel R, Miró C, Wei Y, Wezenberg SJ, Feringa BL. Cation-Modulated Rotary Speed in a Light-Driven Crown Ether Functionalized Molecular Motor. Org Lett 2018; 20:3715-3718. [PMID: 29878791 PMCID: PMC6038094 DOI: 10.1021/acs.orglett.8b00969] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
![]()
The
design and synthesis of an overcrowded-alkene based molecular
motor featuring a crown ether integrated in its stator structure has
been accomplished. The photostationary state ratios and rotational
speed of this motor can be modulated by cation coordination to the
crown ether moiety, which can be reversed upon the addition of a competing
chelating agent, thus achieving a dynamic control over the rotational
behavior of the motor.
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Affiliation(s)
- Ruth Dorel
- Center for Systems Chemistry, Stratingh Institute for Chemistry, Zernike Institute for Advanced Materials , University of Groningen , Nijenborgh 4 , 9747 AG Groningen , The Netherlands
| | - Carla Miró
- Center for Systems Chemistry, Stratingh Institute for Chemistry, Zernike Institute for Advanced Materials , University of Groningen , Nijenborgh 4 , 9747 AG Groningen , The Netherlands
| | - Yuchen Wei
- Center for Systems Chemistry, Stratingh Institute for Chemistry, Zernike Institute for Advanced Materials , University of Groningen , Nijenborgh 4 , 9747 AG Groningen , The Netherlands
| | - Sander J Wezenberg
- Center for Systems Chemistry, Stratingh Institute for Chemistry, Zernike Institute for Advanced Materials , University of Groningen , Nijenborgh 4 , 9747 AG Groningen , The Netherlands
| | - Ben L Feringa
- Center for Systems Chemistry, Stratingh Institute for Chemistry, Zernike Institute for Advanced Materials , University of Groningen , Nijenborgh 4 , 9747 AG Groningen , The Netherlands
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46
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Chantarojsiri T, Ziller JW, Yang JY. Incorporation of redox-inactive cations promotes iron catalyzed aerobic C-H oxidation at mild potentials. Chem Sci 2018; 9:2567-2574. [PMID: 29732136 PMCID: PMC5911827 DOI: 10.1039/c7sc04486k] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 01/28/2018] [Indexed: 12/18/2022] Open
Abstract
The synthesis and characterization of the Schiff base complexes Fe(ii) (2M) and Fe(iii)Cl (3M), where M is a K+ or Ba2+ ion incorporated into the ligand, are reported. The Fe(iii/ii) redox potentials are positively shifted by 440 mV (2K) and 640 mV (2Ba) compared to Fe(salen) (salen = N,N'-bis(salicylidene)ethylenediamine), and by 70 mV (3K) and 230 mV (3Ba) compared to Fe(Cl)(salen), which is likely due to an electrostatic effect (electric field) from the cation. The catalytic activity of 3M towards the aerobic oxidation of allylic C-H bonds was explored. Prior studies on iron salen complexes modified through conventional electron-donating or withdrawing substituents found that only the most oxidizing derivatives were competent catalysts. In contrast, the 3M complexes, which are significantly less oxidizing, are both active. Mechanistic studies comparing 3M to Fe(salen) derivatives indicate that the proximal cation contributes to the overall reactivity in the rate determining step. The cationic charge also inhibits oxidative deactivation through formation of the corresponding Fe2-μ-oxo complexes, which were isolated and characterized. This study demonstrates how non-redox active Lewis acidic cations in the secondary coordination sphere can be used to modify redox catalysts in order to operate at milder potentials with a minimal impact on the reactivity, an effect that was unattainable by tuning the catalyst through traditional substituent effects on the ligand.
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Affiliation(s)
| | - Joseph W Ziller
- Department of Chemistry , University of California , Irvine , 92697 , USA .
| | - Jenny Y Yang
- Department of Chemistry , University of California , Irvine , 92697 , USA .
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Abstract
Crown ethers are useful macrocycles that act as size-selective binding sites for alkali metals. These frameworks have been incorporated into a number of macromolecular assemblies that use simple cations as reporters and/or activity triggers. Incorporating crown ethers into secondary coordination sphere ligand frameworks for transition metal chemistry will lead to new potential methods for controlling bond formation steps, and routes that couple traditional ligand frameworks with these moieties are highly desirable. Herein we report the syntheses of a family of tridentate phosphine complexes bearing tethered aza-crown ethers (lariats) designed to modularize the variation of aza-crown size, lariat length, and distal phosphine substituents, followed by the synthesis and solid-state structures of Mo(III) complexes bearing cations in the pendent crown ethers.
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Affiliation(s)
- Levente G Pap
- Department of Chemistry, University of Wyoming, Dept. 3838, 1000 E. University Avenue, Laramie, Wyoming 82071, United States
| | - Navamoney Arulsamy
- Department of Chemistry, University of Wyoming, Dept. 3838, 1000 E. University Avenue, Laramie, Wyoming 82071, United States
| | - Elliott B Hulley
- Department of Chemistry, University of Wyoming, Dept. 3838, 1000 E. University Avenue, Laramie, Wyoming 82071, United States
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48
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Gregor LC, Grajeda J, White PS, Vetter AJ, Miller AJM. Salt-promoted catalytic methanol carbonylation using iridium pincer-crown ether complexes. Catal Sci Technol 2018. [DOI: 10.1039/c8cy00328a] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Iridium complexes of pincer ligands containing aza-crown ether macrocycles are precatalysts for methanol carbonylation. Turnover numbers for all acetyl-containing products could be tuned from 265 to 1950 using metal and tetrabutylammonium salts.
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Affiliation(s)
- Lauren C. Gregor
- Department of Chemistry
- University of North Carolina at Chapel Hill
- Chapel Hill
- USA
| | - Javier Grajeda
- Department of Chemistry
- University of North Carolina at Chapel Hill
- Chapel Hill
- USA
| | - Peter S. White
- Department of Chemistry
- University of North Carolina at Chapel Hill
- Chapel Hill
- USA
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49
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Wilders AM, Contrella ND, Sampson JR, Zheng M, Jordan RF. Allosteric Effects in Ethylene Polymerization Catalysis. Enhancement of Performance of Phosphine-Phosphinate and Phosphine-Phosphonate Palladium Alkyl Catalysts by Remote Binding of B(C6F5)3. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00815] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Alison M. Wilders
- Department of Chemistry, University of Chicago, 5735 S. Ellis Avenue, Chicago, Illinois 60637, United States
| | - Nathan D. Contrella
- Department of Chemistry, University of Chicago, 5735 S. Ellis Avenue, Chicago, Illinois 60637, United States
| | - Jessica R. Sampson
- Department of Chemistry, University of Chicago, 5735 S. Ellis Avenue, Chicago, Illinois 60637, United States
| | - Mingfang Zheng
- Department of Chemistry, University of Chicago, 5735 S. Ellis Avenue, Chicago, Illinois 60637, United States
| | - Richard F. Jordan
- Department of Chemistry, University of Chicago, 5735 S. Ellis Avenue, Chicago, Illinois 60637, United States
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50
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Cai Z, Do LH. Customizing Polyolefin Morphology by Selective Pairing of Alkali Ions with Nickel Phenoxyimine-Polyethylene Glycol Catalysts. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00516] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Zhongzheng Cai
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
| | - Loi H. Do
- Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, Texas 77004, United States
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