Abstract
Presented are density functional calculations on various Mn(salen) systems that are active catalysts in the epoxidation of olefins. Correlation of various structural properties such as Mn=O bond strengths, atomic charges, and C-O distances of evolving bonds in transition state geometries with modified Hammett constants reveal a mechanistic picture of the epoxidation reaction, supporting previous experimental results. Enantioselectivity is tied to the position of a transition state along the reaction coordinate for the first C-O bond formation step, when an olefin is approaching the epoxidation catalyst. Electronic effects exhibited by the 5,5′ substituents of the salen ligand manifest themselves in a tuning of the Mn=O bond strength, which in turn influences the C-O distance of the forming bond in the transition state geometry.
Original language | English (US) |
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Pages (from-to) | 6202-6207 |
Number of pages | 6 |
Journal | Journal of Organic Chemistry |
Volume | 68 |
Issue number | 16 |
DOIs | |
State | Published - Aug 8 2003 |
Externally published | Yes |
ASJC Scopus subject areas
- Organic Chemistry