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Kim JS, Brandt LM, Heard GL, Holmes BE. Computational study of the threshold energy for the 1,2-interchange of X and R (X, R = halogens, pseudohalogens, and monovalent hydrocarbon groups) on CH2XCH2R. CAN J CHEM 2016. [DOI: 10.1139/cjc-2016-0293] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Transition state geometries and threshold energies, E0, were computed for an unusual unimolecular isomerization reaction that exchanges two groups (X, R) on CH2XCH2R. An objective is to determine the most energetically feasible interchanges to guide experimental investigations. The interchanging species included halogens (F, Cl, Br) and pseudohalogens and monovalent hydrocarbons (H, SH, CH3, NH2, OH, OCF3, OCH3, CH=CH2, CH2CH3, CH2OH, C≡CH, CH2CF3, CCl3, CF3) attached to a two carbon backbone. Ground state and transition state geometries were optimized with the B3PW91 level of theory and 6-311+G(2d,p) basis set. The Br–Br interchange had the lowest E0 (141 kJ/mol), and CH3–H had the highest E0 (582 kJ/mol). In general, larger atoms or groups with lone pairs of electrons such as halogens, SH, OH, OCH3, OCF3, and NH2 tend to lower the E0 barrier for interchange, making them the most likely to be experimentally observed.
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Affiliation(s)
- Ju-Sung Kim
- Department of Chemistry, University of North Carolina Asheville, One University Heights, North Carolina, 28804-8511, USA
- Department of Chemistry, University of North Carolina Asheville, One University Heights, North Carolina, 28804-8511, USA
| | - Laura M. Brandt
- Department of Chemistry, University of North Carolina Asheville, One University Heights, North Carolina, 28804-8511, USA
- Department of Chemistry, University of North Carolina Asheville, One University Heights, North Carolina, 28804-8511, USA
| | - George L. Heard
- Department of Chemistry, University of North Carolina Asheville, One University Heights, North Carolina, 28804-8511, USA
- Department of Chemistry, University of North Carolina Asheville, One University Heights, North Carolina, 28804-8511, USA
| | - Bert E. Holmes
- Department of Chemistry, University of North Carolina Asheville, One University Heights, North Carolina, 28804-8511, USA
- Department of Chemistry, University of North Carolina Asheville, One University Heights, North Carolina, 28804-8511, USA
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Damrauer R, Stanton JF. Studies of 1,2-Dihalo Shifts in Carbon–Carbon, Carbon–Silicon, and Silicon–Silicon Systems: A Computational Study. Organometallics 2012. [DOI: 10.1021/om301019s] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Robert Damrauer
- Chemistry Department, University of Colorado Denver, Campus Box 137, P.O. Box 173364, Denver, Colorado
80217-3364, United States
| | - John F. Stanton
- Chemistry and Biochemistry Department, University of Texas at Austin, Austin, Texas 78712-0165,
United States
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