Activity of Peroxo and Hydroperoxo Complexes of Ti(IV) in Olefin Epoxidation: A Density Functional Model Study of Energetics and Mechanism Full article
| Journal |
European Journal of Inorganic Chemistry
ISSN: 1434-1948 , E-ISSN: 1099-0682 |
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| Output data | Year: 1999, Number: 12, Pages: 2135-2145 Pages count : 11 DOI: 10.1002/(SICI)1099-0682(199912)1999:12<2135::AID-EJIC2135>3.0.CO;2-X | ||||||
| Tags | Density functional calculations, Epoxidation, Peroxo complexes, Titanium, Transition states | ||||||
| Authors |
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| Affiliations |
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Funding (4)
| 1 | Federal Ministry of Science, Research and Economics | 03D0050B |
| 2 | International Association for the Promotion of Co-operation with Scientists from the New Independent States of the Former Soviet Union | IR-97-1071 |
| 3 | Verband der Chemischen Industrie | |
| 4 | German Research Foundation |
Abstract:
Epoxidation of olefins by TiIV peroxo and hydroperoxo (alkylperoxo) complexes was investigated using a hybrid DFT method (B3LYP). Reaction energies and activation barriers for direct oxygen transfer to ethylene as a model olefin were computed for various model complexes to compare the epoxidation activity of Ti(η2-O2) and TiOOR (R = H, CH3) moieties. The activity of complexes with a Ti(O2) peroxo group is shown to be essentially quenched when the coordination sphere of the complex is saturated by strongly basic (σ-donor) ligands. In contrast, the activity of a TiOOH functional group depends only weakly on the saturation of the coordination sphere of the Ti center. Substitution of methyl for hydrogen in a TiOOH group is found to slightly increase the activation barrier of epoxidation. The computational results give preference to reaction paths that involve TiOOR species. The factors governing the activity of Ti(O2) and TiOOR groups, in particular the effects of donor ligands, are discussed on the basis of a molecular orbital analysis.
Cite:
Yudanov I.V.
, Gisdakis P.
, Di Valentin C.
, Rösch N.
Activity of Peroxo and Hydroperoxo Complexes of Ti(IV) in Olefin Epoxidation: A Density Functional Model Study of Energetics and Mechanism
European Journal of Inorganic Chemistry. 1999. N12. P.2135-2145. DOI: 10.1002/(SICI)1099-0682(199912)1999:12<2135::AID-EJIC2135>3.0.CO;2-X WOS Scopus РИНЦ ANCAN OpenAlex OpenAlex
Activity of Peroxo and Hydroperoxo Complexes of Ti(IV) in Olefin Epoxidation: A Density Functional Model Study of Energetics and Mechanism
European Journal of Inorganic Chemistry. 1999. N12. P.2135-2145. DOI: 10.1002/(SICI)1099-0682(199912)1999:12<2135::AID-EJIC2135>3.0.CO;2-X WOS Scopus РИНЦ ANCAN OpenAlex OpenAlex
Dates:
| Submitted: | Jun 18, 1999 |
| Published online: | Nov 15, 1999 |
| Published print: | Dec 1, 1999 |
Identifiers:
| Web of science: | WOS:000083941600005 |
| Scopus: | 2-s2.0-0032700147 |
| Elibrary: | 13320522 |
| Chemical Abstracts: | 1999:761698 |
| Chemical Abstracts (print): | 132:92928 |
| OpenAlex: | W2083073083 | W4241480951 |