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ToolsPaddon-Row, Michael N., Moran, Damian, Jones, Garth A. and Sherburn, Michael S. (2005) On the origin of cis/trans stereoselectivity in intramolecular Diels-Alder reactions of substituted pentadienyl acrylates: A comprehensive density functional study. The Journal of Organic Chemistry, 70 (26). pp. 10841-10853.
Full text not available from this repository.Abstract
A gas-phase B3LYP/6-31+G(d) study of substituent effects on the stereochemistry of both intramolecular Diels-Alder UMDA) reactions of 9-E- and 9-Z-substituted pentadienyl acrylates and intermolecular Diels-Alder (DA) reactions between butadiene and monosubstituted alkenes and 3-substituted acrylates is reported and involves the calculation of 230 transition structures. It was found that, although exo ("anti-Alder") addition of monosubstituted ethenes to butadiene is the norm, Alder endo selectivity is more widely predicted for 3-substituted methyl acrylate dienophiles, and this was explained in terms of secondary orbital interactions (SOIs). Whereas cis/trans selectivity for IMDA reactions involving 9-E-substituted pentadienyl acrylates generally follows the normal pattern found for the corresponding intermolecular DA reactions, the 9-Z-substituted stereoisomers generally displayed trans selectivity that was much stronger than can be attributed to effects of the isolated substituent. This is strikingly so with unsaturated electron-withdrawing substituents whose endo selectivities, displayed in intermolecular DA reactions, are reversed in the IMDA reactions of pentadienyl acrylates. The origin of this anomalous Z-effect is explained in terms of the twist-mode asynchronicity concept of Brown and Houk. These ideas are used to explain the stereochemical outcomes of IMDA reactions of other triene systems.
| Item Type: | Article |
|---|---|
| Faculty \ School: | Faculty of Science > School of Chemistry (former - to 2024) |
| UEA Research Groups: | Faculty of Science > Research Groups > Chemistry of Light and Energy Faculty of Science > Research Groups > Centre for Photonics and Quantum Science |
| Depositing User: | Rachel Smith |
| Date Deposited: | 20 Apr 2011 15:14 |
| Last Modified: | 24 Sep 2024 09:59 |
| URI: | https://ueaeprints.uea.ac.uk/id/eprint/29765 |
| DOI: | 10.1021/jo051973q |
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