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Burgess KMN, Widdifield CM, Xu Y, Leroy C, Bryce DL. Structural Insights from 59 Co Solid-State NMR Experiments on Organocobalt(I) Catalysts. Chemphyschem 2018; 19:227-236. [PMID: 29120533 DOI: 10.1002/cphc.201700990] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 11/08/2017] [Indexed: 11/07/2022]
Abstract
A series of fumarate-based organocobalt(I) [CoCp(CO)(fumarate)] catalysts is synthesized and characterized by X-ray crystallography, multinuclear (13 C and 59 Co) solid-state NMR spectroscopy, and 59 Co NQR spectroscopy. Given the dearth of 59 Co solid-state NMR studies on CoI compounds, the present work constitutes the first systematic characterization of the 59 Co electric field gradient and chemical shift tensors for a series of cobalt complexes in this oxidation state. Using X-ray crystallography, the molecular geometry about the CoI centre is found to be nearly identical in all compounds studied herein. Owing to the 59 Co nucleus' large chemical shift range, solid-state NMR experiments are found to be able to detect small structural differences between the individual organocobalt(I) compounds. With the aid of density functional theory calculations on these complexes, it is shown that the 59 Co chemical shift anisotropy and the 59 Co quadrupolar coupling constant are both extremely sensitive gauges of the Fu-Co-Cp bond angle, providing a link between these 59 Co NMR observables and the catalysts' structures.
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Affiliation(s)
- Kevin M N Burgess
- Department of Chemistry and Biomolecular Sciences, & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
- Current address: St. Peter's Seminary, University of Western Ontario, 1040 Waterloo St., London, ON, N6A 3Y1, Canada
| | - Cory M Widdifield
- Department of Chemistry and Biomolecular Sciences, & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
- Current address: Oakland University, Department of Chemistry, Mathematics and Science Center, 146 Library Drive, Rochester, MI, 48309-4479, USA
| | - Yang Xu
- Department of Chemistry and Biomolecular Sciences, & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
| | - César Leroy
- Department of Chemistry and Biomolecular Sciences, & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
| | - David L Bryce
- Department of Chemistry and Biomolecular Sciences, & Centre for Catalysis Research and Innovation, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
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Grigoleit S, Bühl M. Computational59Co NMR Spectroscopy: Beyond Static Molecules†. J Chem Theory Comput 2005; 1:181-93. [DOI: 10.1021/ct049920o] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kirby CW, Power WP. Cobalt-59 chemical shift and quadrupolar tensors of simple octahedral cobalt(III) complexes. CAN J CHEM 2001. [DOI: 10.1139/v01-025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Analysis of the solid-state powder 59Co NMR spectra of ten simple inorganic cobalt(III) complexes at 11.75, and in most cases, 4.7 T have permitted the assignment of specific ligand planes to ranges of values of the observed chemical shift principal components. The relevant chemical shift components were determined from the simulations of the powder line shapes. These simulations also provided the relative orientations of the chemical shift (CS) and electric field gradient (efg) tensors, as well as magnitude and asymmetry of the 59Co quadrupolar coupling. Using symmetry arguments and ab initio calculations, as appropriate or necessary, the orientations of the efg tensors in the molecular frame were deduced. This allowed the determination of the CS tensors in the molecular frame and thus assignment of the ligand planes responsible for the observed values of chemical shifts.Key words: cobalt, chemical shift, quadrupolar coupling, solid state NMR.
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Eguchi T, Nakayama H, Ohki H, Takeda S, Nakamura N, Kernaghan S, Heaton B. Two-dimensional nutation 59Co NMR of solid Co4(CO)12. J Organomet Chem 1992. [DOI: 10.1016/0022-328x(92)83230-f] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Correlations in Nuclear Magnetic Shielding, Part II. ACTA ACUST UNITED AC 1979. [DOI: 10.1016/s0065-2792(08)60082-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Mooberry ES, Spiess HW, Sheline RK. Quadrupole Coupling and Anisotropic Chemical Shift in Re2(CO)10, Mn2(CO)10, and ReMn(CO)10. J Chem Phys 1972. [DOI: 10.1063/1.1678321] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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