Keith, Jason M.

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  • Keith, Jason M. (2)
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Author's Bibliography

Oxygen atom transfer catalysis: Ligand effects on the key reaction barrier in molybdenum (VI) dioxo systems

Keith, Jason M.; Tomić, Zoran D.; Zarić, Snežana D.; Hall, Michael B.

(2010)

TY  - JOUR
AU  - Keith, Jason M.
AU  - Tomić, Zoran D.
AU  - Zarić, Snežana D.
AU  - Hall, Michael B.
PY  - 2010
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4019
AB  - Catalytic oxygen atom transfer (OAT), which frequently employs molybdenum oxo species, is an important reaction for both nature and industry. The mechanistic details of oxygen atom transfer from Tp(R)MoO(2)(XPh) to PMe(3) were investigated for R = 3-iPr and 3-Me and X=O and S by density functional theory (DFT) calculations of the enthalpies, free energy with solvent corrections, and natural bond orbital (NBO) analysis. The mechanism for both systems proceeds via rate-determining attack of PMe(3) to form a stable intermediate with a bound OPMe(3) ligand. From this intermediate the reaction proceeds through a substitution involving loss of OPMe(3) and coordination of a single CH(3)CN solvent molecule. The solvent corrected free energy barriers of the rate-determining OAT step for the O and S systems were found to be energetically more favorable for the S systems by 6.2 and 2.2 kcal/mol (for the R=3-iPr and 3-Me, respectively). This lower energy barrier is the result of better stabilization by the SPh ligand of the Mo(IV) products and the transition states, which are the unexpectedly later and more product-like. Additional examination of the NBO analysis emphasizes the role of the local acidity of the Mo and by extension the character of the ligands. The decreased electronegativity and softer character of the S atom result in an increased covalent character in the Mo-X bond which leads to the stabilization of a later (and lower energy) transition state and the corresponding product of the S system relative to O system. (C) 2010 Elsevier B.V. All rights reserved.
T2  - Journal of Molecular Catalysis. A: Chemical
T1  - Oxygen atom transfer catalysis: Ligand effects on the key reaction barrier in molybdenum (VI) dioxo systems
VL  - 324
IS  - 1-2
SP  - 15
EP  - 23
DO  - 10.1016/j.molcata.2010.02.027
ER  - 
@article{
author = "Keith, Jason M. and Tomić, Zoran D. and Zarić, Snežana D. and Hall, Michael B.",
year = "2010",
abstract = "Catalytic oxygen atom transfer (OAT), which frequently employs molybdenum oxo species, is an important reaction for both nature and industry. The mechanistic details of oxygen atom transfer from Tp(R)MoO(2)(XPh) to PMe(3) were investigated for R = 3-iPr and 3-Me and X=O and S by density functional theory (DFT) calculations of the enthalpies, free energy with solvent corrections, and natural bond orbital (NBO) analysis. The mechanism for both systems proceeds via rate-determining attack of PMe(3) to form a stable intermediate with a bound OPMe(3) ligand. From this intermediate the reaction proceeds through a substitution involving loss of OPMe(3) and coordination of a single CH(3)CN solvent molecule. The solvent corrected free energy barriers of the rate-determining OAT step for the O and S systems were found to be energetically more favorable for the S systems by 6.2 and 2.2 kcal/mol (for the R=3-iPr and 3-Me, respectively). This lower energy barrier is the result of better stabilization by the SPh ligand of the Mo(IV) products and the transition states, which are the unexpectedly later and more product-like. Additional examination of the NBO analysis emphasizes the role of the local acidity of the Mo and by extension the character of the ligands. The decreased electronegativity and softer character of the S atom result in an increased covalent character in the Mo-X bond which leads to the stabilization of a later (and lower energy) transition state and the corresponding product of the S system relative to O system. (C) 2010 Elsevier B.V. All rights reserved.",
journal = "Journal of Molecular Catalysis. A: Chemical",
title = "Oxygen atom transfer catalysis: Ligand effects on the key reaction barrier in molybdenum (VI) dioxo systems",
volume = "324",
number = "1-2",
pages = "15-23",
doi = "10.1016/j.molcata.2010.02.027"
}
Keith, J. M., Tomić, Z. D., Zarić, S. D.,& Hall, M. B.. (2010). Oxygen atom transfer catalysis: Ligand effects on the key reaction barrier in molybdenum (VI) dioxo systems. in Journal of Molecular Catalysis. A: Chemical, 324(1-2), 15-23.
https://doi.org/10.1016/j.molcata.2010.02.027
Keith JM, Tomić ZD, Zarić SD, Hall MB. Oxygen atom transfer catalysis: Ligand effects on the key reaction barrier in molybdenum (VI) dioxo systems. in Journal of Molecular Catalysis. A: Chemical. 2010;324(1-2):15-23.
doi:10.1016/j.molcata.2010.02.027 .
Keith, Jason M., Tomić, Zoran D., Zarić, Snežana D., Hall, Michael B., "Oxygen atom transfer catalysis: Ligand effects on the key reaction barrier in molybdenum (VI) dioxo systems" in Journal of Molecular Catalysis. A: Chemical, 324, no. 1-2 (2010):15-23,
https://doi.org/10.1016/j.molcata.2010.02.027 . .
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Mechanistic investigations of the oxygen atom transfer from LMoO2(XPh) to PR3

Keith, Jason M.; Hall, Michael B.; Tomić, Zoran D.

(2010)

TY  - CONF
AU  - Keith, Jason M.
AU  - Hall, Michael B.
AU  - Tomić, Zoran D.
PY  - 2010
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6414
C3  - Abstracts of Papers of the American Chemical Society
T1  - Mechanistic investigations of the oxygen atom transfer from LMoO2(XPh) to PR3
VL  - 239
UR  - https://hdl.handle.net/21.15107/rcub_vinar_6414
ER  - 
@conference{
author = "Keith, Jason M. and Hall, Michael B. and Tomić, Zoran D.",
year = "2010",
journal = "Abstracts of Papers of the American Chemical Society",
title = "Mechanistic investigations of the oxygen atom transfer from LMoO2(XPh) to PR3",
volume = "239",
url = "https://hdl.handle.net/21.15107/rcub_vinar_6414"
}
Keith, J. M., Hall, M. B.,& Tomić, Z. D.. (2010). Mechanistic investigations of the oxygen atom transfer from LMoO2(XPh) to PR3. in Abstracts of Papers of the American Chemical Society, 239.
https://hdl.handle.net/21.15107/rcub_vinar_6414
Keith JM, Hall MB, Tomić ZD. Mechanistic investigations of the oxygen atom transfer from LMoO2(XPh) to PR3. in Abstracts of Papers of the American Chemical Society. 2010;239.
https://hdl.handle.net/21.15107/rcub_vinar_6414 .
Keith, Jason M., Hall, Michael B., Tomić, Zoran D., "Mechanistic investigations of the oxygen atom transfer from LMoO2(XPh) to PR3" in Abstracts of Papers of the American Chemical Society, 239 (2010),
https://hdl.handle.net/21.15107/rcub_vinar_6414 .