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Affiliation(s)
- Nicholas Pollak
- Department of Chemistry The University of New Hampshire 23 Academic Way Durham NH 03824 USA
| | - Peipei Huang
- Department of Chemistry The University of New Hampshire 23 Academic Way Durham NH 03824 USA
| | - Hannah Bell
- Department of Chemistry The University of New Hampshire 23 Academic Way Durham NH 03824 USA
| | - Gonghu Li
- Department of Chemistry The University of New Hampshire 23 Academic Way Durham NH 03824 USA
| | - Christine A. Caputo
- Department of Chemistry The University of New Hampshire 23 Academic Way Durham NH 03824 USA
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2
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Abstract
The reaction of the molybdenum-molybdenum triple-bonded dimer (CO)2CpMo≡MoCp(CO)2 (Cp = η5-C5H5) with the triple-bonded dimetallynes AriPr4MMAriPr4 or AriPr6MMAriPr6 (AriPr4 = C6H3-2,6-(C6H3-2,6-Pri2)2, AriPr6 = C6H3-2,6-(C6H2-2,4,6-Pri3)2; M = Ge, Sn, or Pb) under mild conditions (≤80 °C, 1 bar) afforded AriPr4M≡MoCp(CO)2 or AriPr6M≡MoCp(CO)2 in moderate to excellent yields. The reactions represent the first isolable products from a metathesis of two metal-metal triple bonds. Analogous exchange reactions with the single-bonded (CO)3CpMo-MoCp(CO)3 gave ArM̈-MoCp(CO)3 (Ar = AriPr4 or AriPr6; M = Sn or Pb). The products were characterized by NMR (1H, 13C, 119Sn, or 207Pb), electronic, and IR spectroscopy and by X-ray crystallography.
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Affiliation(s)
- Joshua D Queen
- Department of Chemistry , University of California , One Shields Ave , Davis , California 95616 , United States
| | - Alice C Phung
- Department of Chemistry , University of California , One Shields Ave , Davis , California 95616 , United States
| | - Christine A Caputo
- Department of Chemistry , University of California , One Shields Ave , Davis , California 95616 , United States
| | - James C Fettinger
- Department of Chemistry , University of California , One Shields Ave , Davis , California 95616 , United States
| | - Philip P Power
- Department of Chemistry , University of California , One Shields Ave , Davis , California 95616 , United States
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3
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Wakerley D, Lamaison S, Caputo CA. Highlights from Faraday Discussion: Artificial Photosynthesis, Cambridge, UK, March 2019. Chem Commun (Camb) 2019; 55:8351-8358. [DOI: 10.1039/c9cc90252j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This Faraday Discussion was held on March 25–27th, 2019 at Murray Edwards College, Cambridge, UK and was attended by 160 delegates from over 20 countries. In this conference report, the topics of discussion will be outlined with a brief description of the papers presented and a summary of the conference events.
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Aitchison CM, Andrei V, Antón-García D, Apfel UP, Badiani V, Beller M, Bocarsly AB, Bonnet S, Brueggeller P, Caputo CA, Cassiola F, Clausing ST, Cooper AI, Creissen CE, de la Peña O’Shea VA, Domcke W, Durrant JR, Grätzel M, Hammarström L, Hankin A, Hatzell MC, Karadas F, König B, Kuehnel MF, Lamaison S, Lin CY, Maneiro M, Minteer SD, R. Paris A, Pastor E, Pornrungroj C, Reek JNH, Reisner E, Roy S, Sahm C, Shankar R, Shaw WJ, Shylin SI, Smith WA, Sokol K, Soo HS, Sprick RS, Viertl W, Vogel A, Wagner A, Wakerley D, Wang Q, Wielend D, Zwijnenburg MA. Synthetic approaches to artificial photosynthesis: general discussion. Faraday Discuss 2019; 215:242-281. [DOI: 10.1039/c9fd90024a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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5
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Huang P, Huang J, Pantovich SA, Carl AD, Fenton TG, Caputo CA, Grimm RL, Frenkel AI, Li G. Selective CO2 Reduction Catalyzed by Single Cobalt Sites on Carbon Nitride under Visible-Light Irradiation. J Am Chem Soc 2018; 140:16042-16047. [DOI: 10.1021/jacs.8b10380] [Citation(s) in RCA: 212] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Peipei Huang
- Department of Chemistry, University of New Hampshire, Durham, New Hampshire 03857, United States
| | - Jiahao Huang
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, New York 11794, United States
| | - Sebastian A. Pantovich
- Department of Chemistry, University of New Hampshire, Durham, New Hampshire 03857, United States
| | - Alexander D. Carl
- Department of Chemistry & Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, United States
| | - Thomas G. Fenton
- Department of Chemistry, University of New Hampshire, Durham, New Hampshire 03857, United States
| | - Christine A. Caputo
- Department of Chemistry, University of New Hampshire, Durham, New Hampshire 03857, United States
| | - Ronald L. Grimm
- Department of Chemistry & Biochemistry, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, United States
| | - Anatoly I. Frenkel
- Department of Materials Science and Chemical Engineering, Stony Brook University, Stony Brook, New York 11794, United States
- Division of Chemistry, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Gonghu Li
- Department of Chemistry, University of New Hampshire, Durham, New Hampshire 03857, United States
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6
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Wang S, McCrea-Hendrick ML, Weinstein CM, Caputo CA, Hoppe E, Fettinger JC, Olmstead MM, Power PP. Tin(II) Hydrides as Intermediates in Rearrangements of Tin(II) Alkyl Derivatives. J Am Chem Soc 2017; 139:6596-6604. [PMID: 28399365 DOI: 10.1021/jacs.7b02271] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reactions of the Sn(II) hydrides [ArSn(μ-H)]2 (1) (Ar = AriPr4 (1a), AriPr6 (1b); AriP4 = C6H3-2,6-(C6H3-2,6-iPr2)2, AriPr6 = C6H3-2,6-(C6H2-2,4,6-iPr3)2) with norbornene (NB) or norbornadiene (NBD) readily generate the bicyclic alkyl-/alkenyl-substituted stannylenes, ArSn(norbornyl) (2a or 2b) and ArSn(norbornenyl) (3a or 3b), respectively. Heating a toluene solution of 3a or 3b at reflux afforded the rearranged species ArSn(3-tricyclo[2.2.1.02,6]heptane) (4a or 4b), in which the norbornenyl ligand is transformed into a nortricyclyl group. 1H NMR studies of the reactions of 4a or 4b with tert-butylethylene indicated the existence of an apparently unique reversible β-hydride elimination from the bicyclic substituted aryl/alkyl stannylenes 2a or 2b and 3a or 3b. Mechanistic studies indicated that the transformation of 3a or 3b into 4a or 4b occurs via a β-hydride elimination of 1a or 1b to regenerate NBD. Kinetic studies showed that the conversion of 3a or 3b to 4a or 4b is first order. The rate constant k for the conversion of 3a into 3b was determined to be 3.33 × 10-5 min-1, with an activation energy Ea of 16.4 ± 0.7 kcal mol-1.
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Affiliation(s)
- Shuai Wang
- Department of Chemistry, University of California, Davis , 1 Shields Avenue, Davis, California 95616, United States
| | - Madison L McCrea-Hendrick
- Department of Chemistry, University of California, Davis , 1 Shields Avenue, Davis, California 95616, United States
| | - Cory M Weinstein
- Department of Chemistry, University of California, Davis , 1 Shields Avenue, Davis, California 95616, United States
| | - Christine A Caputo
- Department of Chemistry, University of California, Davis , 1 Shields Avenue, Davis, California 95616, United States
| | - Elke Hoppe
- Department of Chemistry, University of California, Davis , 1 Shields Avenue, Davis, California 95616, United States
| | - James C Fettinger
- Department of Chemistry, University of California, Davis , 1 Shields Avenue, Davis, California 95616, United States
| | - Marilyn M Olmstead
- Department of Chemistry, University of California, Davis , 1 Shields Avenue, Davis, California 95616, United States
| | - Philip P Power
- Department of Chemistry, University of California, Davis , 1 Shields Avenue, Davis, California 95616, United States
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7
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Martindale BCM, Hutton GAM, Caputo CA, Prantl S, Godin R, Durrant JR, Reisner E. Enhancing Light Absorption and Charge Transfer Efficiency in Carbon Dots through Graphitization and Core Nitrogen Doping. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201700949] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Benjamin C. M. Martindale
- Christian Doppler Laboratory for Sustainable SynGas Chemistry; Department of Chemistry; University of Cambridge; Lensfield Road Cambridge CB2 1EW UK
| | - Georgina A. M. Hutton
- Christian Doppler Laboratory for Sustainable SynGas Chemistry; Department of Chemistry; University of Cambridge; Lensfield Road Cambridge CB2 1EW UK
| | - Christine A. Caputo
- Christian Doppler Laboratory for Sustainable SynGas Chemistry; Department of Chemistry; University of Cambridge; Lensfield Road Cambridge CB2 1EW UK
- Current address: Department of Chemistry; University of New Hampshire; 23 Academic Way Durham, NH 03824 USA
| | - Sebastian Prantl
- Department of Chemistry; Imperial College London; Exhibition Road London SW7 2AZ UK
| | - Robert Godin
- Department of Chemistry; Imperial College London; Exhibition Road London SW7 2AZ UK
| | - James R. Durrant
- Department of Chemistry; Imperial College London; Exhibition Road London SW7 2AZ UK
| | - Erwin Reisner
- Christian Doppler Laboratory for Sustainable SynGas Chemistry; Department of Chemistry; University of Cambridge; Lensfield Road Cambridge CB2 1EW UK
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8
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Martindale BCM, Hutton GAM, Caputo CA, Prantl S, Godin R, Durrant JR, Reisner E. Enhancing Light Absorption and Charge Transfer Efficiency in Carbon Dots through Graphitization and Core Nitrogen Doping. Angew Chem Int Ed Engl 2017; 56:6459-6463. [DOI: 10.1002/anie.201700949] [Citation(s) in RCA: 164] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/31/2017] [Indexed: 11/10/2022]
Affiliation(s)
- Benjamin C. M. Martindale
- Christian Doppler Laboratory for Sustainable SynGas Chemistry; Department of Chemistry; University of Cambridge; Lensfield Road Cambridge CB2 1EW UK
| | - Georgina A. M. Hutton
- Christian Doppler Laboratory for Sustainable SynGas Chemistry; Department of Chemistry; University of Cambridge; Lensfield Road Cambridge CB2 1EW UK
| | - Christine A. Caputo
- Christian Doppler Laboratory for Sustainable SynGas Chemistry; Department of Chemistry; University of Cambridge; Lensfield Road Cambridge CB2 1EW UK
- Current address: Department of Chemistry; University of New Hampshire; 23 Academic Way Durham, NH 03824 USA
| | - Sebastian Prantl
- Department of Chemistry; Imperial College London; Exhibition Road London SW7 2AZ UK
| | - Robert Godin
- Department of Chemistry; Imperial College London; Exhibition Road London SW7 2AZ UK
| | - James R. Durrant
- Department of Chemistry; Imperial College London; Exhibition Road London SW7 2AZ UK
| | - Erwin Reisner
- Christian Doppler Laboratory for Sustainable SynGas Chemistry; Department of Chemistry; University of Cambridge; Lensfield Road Cambridge CB2 1EW UK
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9
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Wang S, McCrea-Hendrick ML, Weinstein CM, Caputo CA, Hoppe E, Fettinger JC, Olmstead MM, Power PP. Dynamic Behavior and Isomerization Equilibria of Distannenes Synthesized by Tin Hydride/Olefin Insertions: Characterization of the Elusive Monohydrido Bridged Isomer. J Am Chem Soc 2017; 139:6586-6595. [DOI: 10.1021/jacs.7b02269] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shuai Wang
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
| | - Madison L. McCrea-Hendrick
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
| | - Cory M. Weinstein
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
| | - Christine A. Caputo
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
| | - Elke Hoppe
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
| | - James C. Fettinger
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
| | - Marilyn M. Olmstead
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
| | - Philip P. Power
- Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, United States
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10
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Hutton GAM, Reuillard B, Martindale BCM, Caputo CA, Lockwood CWJ, Butt JN, Reisner E. Carbon Dots as Versatile Photosensitizers for Solar-Driven Catalysis with Redox Enzymes. J Am Chem Soc 2016; 138:16722-16730. [PMID: 27977174 DOI: 10.1021/jacs.6b10146] [Citation(s) in RCA: 160] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Light-driven enzymatic catalysis is enabled by the productive coupling of a protein to a photosensitizer. Photosensitizers used in such hybrid systems are typically costly, toxic, and/or fragile, with limited chemical versatility. Carbon dots (CDs) are low-cost, nanosized light-harvesters that are attractive photosensitizers for biological systems as they are water-soluble, photostable, nontoxic, and their surface chemistry can be easily modified. We demonstrate here that CDs act as excellent light-absorbers in two semibiological photosynthetic systems utilizing either a fumarate reductase (FccA) for the solar-driven hydrogenation of fumarate to succinate or a hydrogenase (H2ase) for reduction of protons to H2. The tunable surface chemistry of the CDs was exploited to synthesize positively charged ammonium-terminated CDs (CD-NHMe2+), which were capable of transferring photoexcited electrons directly to the negatively charged enzymes with high efficiency and stability. Enzyme-based turnover numbers of 6000 mol succinate (mol FccA)-1 and 43,000 mol H2 (mol H2ase)-1 were reached after 24 h. Negatively charged carboxylate-terminated CDs (CD-CO2-) displayed little or no activity, and the electrostatic interactions at the CD-enzyme interface were determined to be essential to the high photocatalytic activity observed with CD-NHMe2+. The modular surface chemistry of CDs together with their photostability and aqueous solubility make CDs versatile photosensitizers for redox enzymes with great scope for their utilization in photobiocatalysis.
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Affiliation(s)
- Georgina A M Hutton
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, U.K
| | - Bertrand Reuillard
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, U.K
| | | | - Christine A Caputo
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, U.K
| | - Colin W J Lockwood
- School of Chemistry and School of Biological Sciences, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Julea N Butt
- School of Chemistry and School of Biological Sciences, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Erwin Reisner
- Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, U.K
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11
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McCrea-Hendrick ML, Caputo CA, Linnera J, Vasko P, Weinstein CM, Fettinger JC, Tuononen HM, Power PP. Cleavage of Ge–Ge and Sn–Sn Triple Bonds in Heavy Group 14 Element Alkyne Analogues (EAriPr4)2 (E = Ge, Sn; AriPr4 = C6H3-2,6(C6H3-2,6-iPr2)2) by Reaction with Group 6 Carbonyls. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00519] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Madison L. McCrea-Hendrick
- Department of Chemistry, University of California Davis, 1 Shields Avenue, Davis, California 95616, United States
| | - Christine A. Caputo
- Department of Chemistry, University of California Davis, 1 Shields Avenue, Davis, California 95616, United States
| | - Jarno Linnera
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
| | - Petra Vasko
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
| | - Cory M. Weinstein
- Department of Chemistry, University of California Davis, 1 Shields Avenue, Davis, California 95616, United States
| | - James C. Fettinger
- Department of Chemistry, University of California Davis, 1 Shields Avenue, Davis, California 95616, United States
| | - Heikki M. Tuononen
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
| | - Philip P. Power
- Department of Chemistry, University of California Davis, 1 Shields Avenue, Davis, California 95616, United States
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12
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McCrea-Hendrick ML, Caputo CA, Roberts CJ, Fettinger JC, Tuononen HM, Power PP. Reactions of Terphenyl-Substituted Digallene AriPr4GaGaAriPr4 (AriPr4 = C6H3-2,6-(C6H3-2,6-iPr2)2) with Transition Metal Carbonyls and Theoretical Investigation of the Mechanism of Addition. Organometallics 2016. [DOI: 10.1021/acs.organomet.5b00992] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Madison L. McCrea-Hendrick
- Department
of Chemistry, The University of California Davis, 1 Shields Avenue, Davis, California 95616, United States
| | - Christine A. Caputo
- Department
of Chemistry, The University of California Davis, 1 Shields Avenue, Davis, California 95616, United States
| | - Christopher J. Roberts
- Department
of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box
35, Jyväskylä FI-40014, Finland
| | - James C. Fettinger
- Department
of Chemistry, The University of California Davis, 1 Shields Avenue, Davis, California 95616, United States
| | - Heikki M. Tuononen
- Department
of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box
35, Jyväskylä FI-40014, Finland
| | - Philip P. Power
- Department
of Chemistry, The University of California Davis, 1 Shields Avenue, Davis, California 95616, United States
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Tashkandi NY, Pavelka LC, Caputo CA, Boyle PD, Power PP, Baines KM. Addition of alkynes to digermynes: experimental insight into the reaction pathway. Dalton Trans 2016; 45:7226-30. [DOI: 10.1039/c6dt01015f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction pathway for the addition of alkynes to digermynes has been investigated using a mechanistic probe approach.
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Affiliation(s)
| | - Laura C. Pavelka
- Department of Chemistry
- University of Western Ontario
- London
- Canada
| | | | - Paul D. Boyle
- Department of Chemistry
- University of Western Ontario
- London
- Canada
| | - Philip P. Power
- Department of Chemistry
- University of California at Davis
- Davis
- USA
| | - Kim M. Baines
- Department of Chemistry
- University of Western Ontario
- London
- Canada
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Abstract
The development of technology for the inexpensive generation of the renewable energy vector H2 through water splitting is of immediate economic, ecological, and humanitarian interest. Recent interest in hydrogenases has been fueled by their exceptionally high catalytic rates for H2 production at a marginal overpotential, which is presently only matched by the nonscalable noble metal platinum. The mechanistic understanding of hydrogenase function guides the design of synthetic catalysts, and selection of a suitable hydrogenase enables direct applications in electro- and photocatalysis. [FeFe]-hydrogenases display excellent H2 evolution activity, but they are irreversibly damaged upon exposure to O2, which currently prevents their use in full water splitting systems. O2-tolerant [NiFe]-hydrogenases are known, but they are typically strongly biased toward H2 oxidation, while H2 production by [NiFe]-hydrogenases is often product (H2) inhibited. [NiFeSe]-hydrogenases are a subclass of [NiFe]-hydrogenases with a selenocysteine residue coordinated to the active site nickel center in place of a cysteine. They exhibit a combination of unique properties that are highly advantageous for applications in water splitting compared with other hydrogenases. They display a high H2 evolution rate with marginal inhibition by H2 and tolerance to O2. [NiFeSe]-hydrogenases are therefore one of the most active molecular H2 evolution catalysts applicable in water splitting. Herein, we summarize our recent progress in exploring the unique chemistry of [NiFeSe]-hydrogenases through biomimetic model chemistry and the chemistry with [NiFeSe]-hydrogenases in semiartificial photosynthetic systems. We gain perspective from the structural, spectroscopic, and electrochemical properties of the [NiFeSe]-hydrogenases and compare them with the chemistry of synthetic models of this hydrogenase active site. Our synthetic models give insight into the effects on the electronic properties and reactivity of the active site upon the introduction of selenium. We have utilized the exceptional properties of the [NiFeSe]-hydrogenase from Desulfomicrobium baculatum in a number of photocatalytic H2 production schemes, which are benchmark systems in terms of single site activity, tolerance toward O2, and in vitro water splitting with biological molecules. Each system comprises a light-harvesting component, which allows for light-driven electron transfer to the hydrogenase in order for it to catalyze H2 production. A system with [NiFeSe]-hydrogenase on a dye-sensitized TiO2 nanoparticle gives an enzyme-semiconductor hybrid for visible light-driven generation of H2 with an enzyme-based turnover frequency of 50 s(-1). A stable and inexpensive polymeric carbon nitride as a photosensitizer in combination with the [NiFeSe]-hydrogenase shows good activity for more than 2 days. Light-driven H2 evolution with the enzyme and an organic dye under high O2 levels demonstrates the excellent robustness and feasibility of water splitting with a hydrogenase-based scheme. This has led, most recently, to the development of a light-driven full water splitting system with a [NiFeSe]-hydrogenase wired to the water oxidation enzyme photosystem II in a photoelectrochemical cell. In contrast to the other systems, this photoelectrochemical system does not rely on a sacrificial electron donor and allowed us to establish the long sought after light-driven water splitting with an isolated hydrogenase.
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Affiliation(s)
- Claire Wombwell
- Christian Doppler Laboratory
for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Christine A. Caputo
- Christian Doppler Laboratory
for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Erwin Reisner
- Christian Doppler Laboratory
for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
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15
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Caputo CA, Wang L, Beranek R, Reisner E. Carbon nitride-TiO 2 hybrid modified with hydrogenase for visible light driven hydrogen production. Chem Sci 2015; 6:5690-5694. [PMID: 28757952 PMCID: PMC5512016 DOI: 10.1039/c5sc02017d] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 06/29/2015] [Indexed: 01/18/2023] Open
Abstract
A system consisting of a [NiFeSe]-hydrogenase (H2ase) grafted on the surface of a TiO2 nanoparticle modified with polyheptazine carbon nitride polymer, melon (CN x ) is reported. This semi-biological assembly shows a turnover number (TON) of more than 5.8 × 105 mol H2 (mol H2ase)-1 after 72 h in a sacrificial electron donor solution at pH 6 during solar AM 1.5 G irradiation. An external quantum efficiency up to 4.8% for photon-to-hydrogen conversion was achieved under irradiation with monochromatic light. The CN x -TiO2-H2ase construct was also active under UV-free solar light irradiation (λ > 420 nm), where it showed a substantially higher activity than TiO2-H2ase and CN x -H2ase due, in part, to the formation of a CN x -TiO2 charge transfer complex and highly productive electron transfer to the H2ase. The CN x -TiO2-H2ase system sets a new benchmark for photocatalytic H2 production with a H2ase immobilised on a noble- and toxic-metal free light absorber in terms of visible light utilisation and stability.
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Affiliation(s)
- Christine A Caputo
- Christian Doppler Laboratory for Sustainable SynGas Chemistry , Department of Chemistry , Cambridge University , Lensfied Road , Cambridge CB2 1EW , UK . ; http://www-reisner.ch.cam.ac.uk
| | - Lidong Wang
- Faculty of Chemistry and Biochemistry , Ruhr-Universität Bochum , Universitätsstraße 150 , 44780 Bochum , Germany
| | - Radim Beranek
- Faculty of Chemistry and Biochemistry , Ruhr-Universität Bochum , Universitätsstraße 150 , 44780 Bochum , Germany
| | - Erwin Reisner
- Christian Doppler Laboratory for Sustainable SynGas Chemistry , Department of Chemistry , Cambridge University , Lensfied Road , Cambridge CB2 1EW , UK . ; http://www-reisner.ch.cam.ac.uk
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Martindale BCM, Hutton GAM, Caputo CA, Reisner E. Solar hydrogen production using carbon quantum dots and a molecular nickel catalyst. J Am Chem Soc 2015; 137:6018-25. [PMID: 25864839 DOI: 10.1021/jacs.5b01650] [Citation(s) in RCA: 287] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Carbon quantum dots (CQDs) are established as excellent photosensitizers in combination with a molecular catalyst for solar light driven hydrogen production in aqueous solution. The inexpensive CQDs can be prepared by straightforward thermolysis of citric acid in a simple one-pot, multigram synthesis and are therefore scalable. The CQDs produced reducing equivalents under solar irradiation in a homogeneous photocatalytic system with a Ni-bis(diphosphine) catalyst, giving an activity of 398 μmolH2 (gCQD)(-1) h(-1) and a "per Ni catalyst" turnover frequency of 41 h(-1). The CQDs displayed activity in the visible region beyond λ > 455 nm and maintained their full photocatalytic activity for at least 1 day under full solar spectrum irradiation. A high quantum efficiency of 1.4% was recorded for the noble- and toxic-metal free photocatalytic system. Thus, CQDs are shown to be a highly sustainable light-absorbing material for photocatalytic schemes, which are not limited by cost, toxicity, or lack of scalability. The photocatalytic hybrid system was limited by the lifetime of the molecular catalyst, and intriguingly, no photocatalytic activity was observed using the CQDs and 3d transition metal salts or platinum precursors. This observation highlights the advantage of using a molecular catalyst over commonly used heterogeneous catalysts in this photocatalytic system.
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Affiliation(s)
- Benjamin C M Martindale
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Georgina A M Hutton
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Christine A Caputo
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Erwin Reisner
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
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Caputo CA, Gross MA, Lau VW, Cavazza C, Lotsch BV, Reisner E. Photocatalytic hydrogen production using polymeric carbon nitride with a hydrogenase and a bioinspired synthetic Ni catalyst. Angew Chem Int Ed Engl 2014; 53:11538-42. [PMID: 25205168 PMCID: PMC4497605 DOI: 10.1002/anie.201406811] [Citation(s) in RCA: 157] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 08/07/2014] [Indexed: 11/30/2022]
Abstract
Solar-light-driven H2 production in water with a [NiFeSe]-hydrogenase (H2ase) and a bioinspired synthetic nickel catalyst (NiP) in combination with a heptazine carbon nitride polymer, melon (CN(x)), is reported. The semibiological and purely synthetic systems show catalytic activity during solar light irradiation with turnover numbers (TONs) of more than 50,000 mol H2(mol H2ase)(-1) and approximately 155 mol H2 (mol NiP)(-1) in redox-mediator-free aqueous solution at pH 6 and 4.5, respectively. Both systems maintained a reduced photoactivity under UV-free solar light irradiation (λ>420 nm).
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Affiliation(s)
- Christine A Caputo
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of CambridgeLensfield Road, Cambridge CB2 1EW (UK)
| | - Manuela A Gross
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of CambridgeLensfield Road, Cambridge CB2 1EW (UK)
| | - Vincent W Lau
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of CambridgeLensfield Road, Cambridge CB2 1EW (UK)
| | - Christine Cavazza
- CEA, CNRS, Université Grenoble Alpes, IBS71 Avenue des Martyrs, 38044 Grenoble (France)
| | - Bettina V Lotsch
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of CambridgeLensfield Road, Cambridge CB2 1EW (UK)
| | - Erwin Reisner
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of CambridgeLensfield Road, Cambridge CB2 1EW (UK)
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Caputo CA, Gross MA, Lau VW, Cavazza C, Lotsch BV, Reisner E. Photocatalytic Hydrogen Production using Polymeric Carbon Nitride with a Hydrogenase and a Bioinspired Synthetic Ni Catalyst. ACTA ACUST UNITED AC 2014; 126:11722-11726. [PMID: 26300567 PMCID: PMC4535659 DOI: 10.1002/ange.201406811] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 08/07/2014] [Indexed: 11/30/2022]
Abstract
Solar-light-driven H2 production in water with a [NiFeSe]-hydrogenase (H2ase) and a bioinspired synthetic nickel catalyst (NiP) in combination with a heptazine carbon nitride polymer, melon (CNx), is reported. The semibiological and purely synthetic systems show catalytic activity during solar light irradiation with turnover numbers (TONs) of more than 50 000 mol H2 (mol H2ase)−1 and approximately 155 mol H2 (mol NiP)−1 in redox-mediator-free aqueous solution at pH 6 and 4.5, respectively. Both systems maintained a reduced photoactivity under UV-free solar light irradiation (λ>420 nm).
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Affiliation(s)
- Christine A Caputo
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge Lensfield Road, Cambridge CB2 1EW (UK) E-mail: Homepage: http://www-reisner.ch.cam.ac.uk/
| | - Manuela A Gross
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge Lensfield Road, Cambridge CB2 1EW (UK) E-mail: Homepage: http://www-reisner.ch.cam.ac.uk/
| | - Vincent W Lau
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge Lensfield Road, Cambridge CB2 1EW (UK) E-mail: Homepage: http://www-reisner.ch.cam.ac.uk/
| | - Christine Cavazza
- CEA, CNRS, Université Grenoble Alpes IBS, 71 Avenue des Martyrs, 38044 Grenoble (France)
| | - Bettina V Lotsch
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge Lensfield Road, Cambridge CB2 1EW (UK) E-mail: Homepage: http://www-reisner.ch.cam.ac.uk/
| | - Erwin Reisner
- Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge Lensfield Road, Cambridge CB2 1EW (UK) E-mail: Homepage: http://www-reisner.ch.cam.ac.uk/
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Abstract
Two modes of reactivity are observed when pyrophoric phosphine gas reacts with diaryltetrylenes, representing unique main-group P–H bond activation.
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Affiliation(s)
- Jonathan W. Dube
- Department of Chemistry and Center for Advanced Materials and Biomaterials Research (CAMBR)
- The University of Western Ontario
- London, Canada
| | | | | | - Philip P. Power
- Department of Chemistry
- The University of California
- Davis, USA
| | - Paul J. Ragogna
- Department of Chemistry and Center for Advanced Materials and Biomaterials Research (CAMBR)
- The University of Western Ontario
- London, Canada
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Affiliation(s)
- Christine A. Caputo
- Department of Chemistry, The University of California at Davis, 1 Shields Avenue, Davis, California
95616, United States
| | - Philip P. Power
- Department of Chemistry, The University of California at Davis, 1 Shields Avenue, Davis, California
95616, United States
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Caputo CA, Koivistoinen J, Moilanen J, Boynton JN, Tuononen HM, Power PP. Counterintuitive Mechanisms of the Addition of Hydrogen and Simple Olefins to Heavy Group 13 Alkene Analogues. J Am Chem Soc 2013; 135:1952-60. [DOI: 10.1021/ja3116789] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christine A. Caputo
- Department
of Chemistry, The University of California Davis, 1 Shields Avenue,
Davis, California 95616, United States
| | - Juha Koivistoinen
- Department of Chemistry, University of Jyväskylä, P.O. Box 35,
FI-40014 Jyväskylä, Finland
| | - Jani Moilanen
- Department of Chemistry, University of Jyväskylä, P.O. Box 35,
FI-40014 Jyväskylä, Finland
| | - Jessica N. Boynton
- Department
of Chemistry, The University of California Davis, 1 Shields Avenue,
Davis, California 95616, United States
| | - Heikki M. Tuononen
- Department of Chemistry, University of Jyväskylä, P.O. Box 35,
FI-40014 Jyväskylä, Finland
| | - Philip P. Power
- Department
of Chemistry, The University of California Davis, 1 Shields Avenue,
Davis, California 95616, United States
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Summerscales OT, Caputo CA, Knapp CE, Fettinger JC, Power PP. The role of group 14 element hydrides in the activation of C-H bonds in cyclic olefins. J Am Chem Soc 2012; 134:14595-603. [PMID: 22916997 DOI: 10.1021/ja305853d] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Formally, triple-bonded dimetallynes ArEEAr [E = Ge (1), Sn (2); Ar = C(6)H(3)-2,6-(C(6)H(3)-2,6-(i)Pr(2))(2)] have been previously shown to activate aliphatic, allylic C-H bonds in cyclic olefins, cyclopentadiene (CpH), cyclopentene (c-C(5)H(8)) and 1,4-cyclohexadiene, with intriguing selectivity. In the case of the five-membered carbocycles, cyclopentadienyl species ArECp [E = Ge (3), Sn (4)] are formed. In this study, we examine the mechanisms for activation of CpH and c-C(5)H(8) using experimental methods and describe a new product found from the reaction between 1 and c-C(5)H(8), an asymmetrically substituted digermene ArGe(H)Ge(c-C(5)H(9))Ar (5), crystallized in 46% yield. This compound contains a hydrogenated cyclopentyl moiety and is found to be produced in a 3:2 ratio with 3, explaining the fate of the liberated H atoms following triple C-H activation. We show that when these C-H activation reactions are carried out in the presence of tert-butyl ethylene (excess), compounds {ArE(CH(2)CH(2)tBu)}(2) [E = Ge(8), Sn(9)] are obtained in addition to ArECp; in the case of CpH, the neohexyl complexes replace the production of H(2) gas, and for c-C(5)H(8) they displace cyclopentyl product 5 and account for all the hydrogen removed in the dehydroaromatization reactions. To confirm the source of 8 and 9, it was demonstrated that these molecules are formed cleanly between the reaction of (ArEH)(2) [E = Ge(6), Sn(7)] and tert-butyl ethylene, new examples of noncatalyzed hydro-germylation and -stannylation. Therefore, the presence of transient hydrides of the type 6 and 7 can be surmised to be reactive intermediates in the production of 3 and 4, along with H(2), from 1 and 2 and CpH (respectively), or the formation of 3 and 5 from 1. The reaction of 6 or 7 with CpH gave 3 or 4, respectively, with concomitant H(2) evolution, demonstrating the basic nature of these low-valent group 14 element hydrides and their key role in the 'cascade' of C-H activation steps. Additionally, during the course of these studies a new polycyclic compound (ArGe)(2)(C(7)H(12)) (10) was obtained in 60% yield from the reaction of 1,6-heptadiene and 1 via double [2 + 2] cycloaddition and gives evidence for a nonradical mechanism for these types of reactions.
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Affiliation(s)
- Owen T Summerscales
- Department of Chemistry, University of California, Davis, California 95616, USA
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Caputo CA, Guo JD, Nagase S, Fettinger JC, Power PP. Reversible and Irreversible Higher-Order Cycloaddition Reactions of Polyolefins with a Multiple-Bonded Heavier Group 13 Alkene Analogue: Contrasting the Behavior of Systems with π–π, π–π*, and π–n+ Frontier Molecular Orbital Symmetry. J Am Chem Soc 2012; 134:7155-64. [DOI: 10.1021/ja301247h] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christine A. Caputo
- Department
of Chemistry, University of California, Davis, 1 Shields Avenue,
Davis, California 95616, United States
| | - Jing-Dong Guo
- Department of Theoretical and
Computational Molecular Science, Institute for Molecular Science, Okazaki, Aichi 444-8585, Japan
| | - Shigeru Nagase
- Department of Theoretical and
Computational Molecular Science, Institute for Molecular Science, Okazaki, Aichi 444-8585, Japan
| | - James C. Fettinger
- Department
of Chemistry, University of California, Davis, 1 Shields Avenue,
Davis, California 95616, United States
| | - Philip P. Power
- Department
of Chemistry, University of California, Davis, 1 Shields Avenue,
Davis, California 95616, United States
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Caputo CA, Zhu Z, Brown ZD, Fettinger JC, Power PP. Activation of olefins with low-valent gallium compounds under ambient conditions. Chem Commun (Camb) 2011; 47:7506-8. [DOI: 10.1039/c1cc11676b] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Brazeau AL, Caputo CA, Martin CD, Jones ND, Ragogna PJ. A new approach to internal Lewis pairs featuring a phosphenium acid and a pyridine base. Dalton Trans 2010; 39:11069-73. [DOI: 10.1039/c0dt01029d] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Caputo CA, Brazeau AL, Hynes Z, Price JT, Tuononen HM, Jones ND. A Cation-Captured Palladium(0) Anion: Synthesis, Structure, and Bonding of [PdBr(PPh3)2]− Ligated by an N-Heterocyclic Phosphenium Cation. Organometallics 2009. [DOI: 10.1021/om9006278] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christine A. Caputo
- Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario, Canada N6A 5B7
| | - Allison L. Brazeau
- Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario, Canada N6A 5B7
| | - Zachery Hynes
- Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario, Canada N6A 5B7
| | - Jacquelyn T. Price
- Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario, Canada N6A 5B7
| | - Heikki M. Tuononen
- Department of Chemistry, University of Jyväskylä, P.O. Box 35, Fl-40014, Jyväskylä, Finland
| | - Nathan D. Jones
- Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario, Canada N6A 5B7
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Caputo CA, Jennings MC, Tuononen HM, Jones ND. Phospha-Fischer Carbenes: Synthesis, Structure, Bonding, and Reactions of Pd(0)− and Pt(0)−Phosphenium Complexes. Organometallics 2009. [DOI: 10.1021/om800973v] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christine A. Caputo
- Department of Chemistry, The University of Western Ontario, London, Ontario, Canada N6A 5B7, and Department of Chemistry, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - Michael C. Jennings
- Department of Chemistry, The University of Western Ontario, London, Ontario, Canada N6A 5B7, and Department of Chemistry, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - Heikki M. Tuononen
- Department of Chemistry, The University of Western Ontario, London, Ontario, Canada N6A 5B7, and Department of Chemistry, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland
| | - Nathan D. Jones
- Department of Chemistry, The University of Western Ontario, London, Ontario, Canada N6A 5B7, and Department of Chemistry, University of Jyväskylä, P.O. Box 35, FI-40014 Jyväskylä, Finland
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Caputo CA, Price JT, Jennings MC, McDonald R, Jones ND. N-Heterocyclic phosphenium cations: syntheses and cycloaddition reactions. Dalton Trans 2008:3461-9. [DOI: 10.1039/b801684d] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Caputo CA, Carneiro FDS, Jennings MC, Jones ND. Modular syntheses of oxazolinylamine ligands and characterization of group 10 metal complexes. CAN J CHEM 2007. [DOI: 10.1139/v06-188] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The syntheses of aminoalkyloxazoline and pyrrolidinyloxazoline ligands, each of which bear a pair of chiral centres, by both known and new routes are reported. Variable temperature NMR studies show that the known stepwise syntheses of the pyrrolidinyl compounds are not complicated by epimerization; however, coordination of one of the aminoalkyl derivatives to Pt(II) under conditions of prolonged heating to 80 °C does give mixtures of diastereomeric N,N ′-chelated complexes that result from inversion of the chiral centre associated with the aminoalkyl fragment. A new synthesis of pyrrolidinyloxazoline ligands that involves the Zn-catalyzed cyclization of Cbz-protected 2-cyanopyrrolidine and β-amino alcohols is also reported. This procedure offers the advantages of economy, shorter time, and fewer purification steps over the previously reported synthesis. In addition, the crystal structure of an enantiopure Pd(II) complex of an N,N ′-chelated pyrrolidinyloxazoline is disclosed. This compound has a pseudo-C2 axis of symmetry, which may make it suitable for asymmetric catalytic applications.Key words: chiral ligands, ligand design, oxazolines, variable temperature NMR spectroscopy, asymmetric catalysis, coordination compounds, palladium, platinum
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Caputo CA, Jones ND. Developments in asymmetric catalysis by metal complexes of chiral chelating nitrogen-donor ligands. Dalton Trans 2007:4627-40. [DOI: 10.1039/b709283k] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Barriga OO, Caputo CA, Weisbrode SE. Liver flukes (Platynosomum concinnum) in an Ohio cat. J Am Vet Med Assoc 1981; 179:901-3. [PMID: 7341605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Kociba GJ, Caputo CA. Aplastic anemia associated with estrus in pet ferrets. J Am Vet Med Assoc 1981; 178:1293-4. [PMID: 7196908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Aplastic anemia in association with estrus was diagnosed in 6 pet ferrets. The ferrets had been examined because of anorexia, depression, and lethargy of 2-5 days' duration. Consistent clinical findings were pale mucous membranes and enlargement of the vulva. Hemorrhages were found in 3 ferrets. Hematologic findings included severe anemia, thrombocytopenia, granulocytopenia, and hypocellularity of the bone marrow. The aplastic anemia was attributed to prolonged estrogenic exposure in ferrets with protracted estrus.
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Fava LR, Caputo CA. [New technics in biomechanical preparation: scaled and incremental biomechanical preparation-II]. Ars Curandi Odontol 1979; 6:4-18. [PMID: 397815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Fava LR, Caputo CA. [New technics for biomechanical preparation: escalated biomechanical preparation and incremental preparation. I]. Ars Curandi Odontol 1979; 5:4-14. [PMID: 288377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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