| Autor: |
Joy J; Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84604, United States., Schaefer AJ; Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84604, United States., Teynor MS; Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84604, United States., Ess DH; Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84604, United States. |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of the American Chemical Society [J Am Chem Soc] 2024 Jan 31; Vol. 146 (4), pp. 2452-2464. Date of Electronic Publication: 2024 Jan 19. |
| DOI: |
10.1021/jacs.3c09891 |
| Abstrakt: |
The mechanism of catalytic C-H functionalization of alkanes by Fe-oxo complexes is often suggested to involve a hydrogen atom transfer (HAT) step with the formation of a radical-pair intermediate followed by diverging pathways for radical rebound, dissociation, or desaturation. Recently, we showed that in some Fe-oxo reactions, the radical pair is a nonstatistical-type intermediate and dynamic effects control rebound versus dissociation pathway selectivity. However, the effect of the solvent cage on the stability and lifetime of the radical-pair intermediate has never been analyzed. Moreover, because of the extreme complexity of motion that occurs during dynamics trajectories, the underlying physical origin of pathway selectivity has not yet been determined. For the reaction between [(TQA_Cl)Fe IV O] + and cyclohexane, here, we report explicit solvent trajectories and machine learning analysis on transition-state sampled features (e.g., vibrational, velocity, and geometric) that identified the transferring hydrogen atom kinetic energy as the most important factor controlling rebound versus nonrebound dynamics trajectories, which provides an explanation for our previously proposed dynamic matching effect in fast rebound trajectories that bypass the radical-pair intermediate. Manual control of the reaction trajectories confirmed the importance of this feature and provides a mechanism to enhance or diminish selectivity for the rebound pathway. This led to a general catalyst design principle and proof-of-principle catalyst design that showcases how to control rebound versus dissociation reaction pathway selectivity. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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