Effect of electron-withdrawing group on the [3,3]-sigmatropicrearrangements of 1,5-enynes, 1,5-diynes and 1,2-diene-5-ynes: Atheoretical study
文献类型：期刊论文
| 作者 | Xia, Yuanzhi ; Zhou, Fengying ; Li, Yahong ; Lia, Wu |
| 刊名 | JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM
 |
| 出版日期 | 2009 |
| 卷号 | 904期号:1-3页码:69-73 |
| 关键词 | Cope rearrangement Electronic effect Theoretical calculation |
| ISSN号 | 0166-1280 |
| 语种 | The electronic effects of an electron-withdrawing group (exemplified by formyl group) on the kinetic and thermodynamic aspects of substituted 1,5-enyne. 1,5-diyne, and 1,2-diene-5-yne Cope rearrangements were investigated by means of DFT and CBS-QB3 calculations. The energy barriers of the formyl substituted reactions are lower than those of the unsubstituted ones almost in all cases, and the barriers will be further lowered when catalyzed by ACl(3), The most obvious electronic effect was calculated for the C-2 formyl substituted 1,5-enyne rearrangements, which have activation barriers of 27.1 and 18.1 kcal/mol, respectively, for the uncatalyzed and catalyzed reactions. The charge transfer induced by the electron-withdrawing group and stabilization of the charge by Lewis acid are responsible for the different energetic profiles. The formyl substitution will change the thermodynamic profiles of the transformations, notablely, increase the reaction enthalpies of the 1,5-diyne and 1,2-diene-5-yne rearrangements by over 5.0 kcal/mol, as result of the stabilization effect of a formyl substitution attached directly to the unsaturated moieties of the products. (c) 2009 Elsevier B.V. All rights reserved. The electronic effects of an electron-withdrawing group (exemplified by formyl group) on the kinetic and thermodynamic aspects of substituted 1,5-enyne. 1,5-diyne, and 1,2-diene-5-yne Cope rearrangements were investigated by means of DFT and CBS-QB3 calculations. The energy barriers of the formyl substituted reactions are lower than those of the unsubstituted ones almost in all cases, and the barriers will be further lowered when catalyzed by ACl(3), The most obvious electronic effect was calculated for the C-2 formyl substituted 1,5-enyne rearrangements, which have activation barriers of 27.1 and 18.1 kcal/mol, respectively, for the uncatalyzed and catalyzed reactions. The charge transfer induced by the electron-withdrawing group and stabilization of the charge by Lewis acid are responsible for the different energetic profiles. The formyl substitution will change the thermodynamic profiles of the transformations, notablely, increase the reaction enthalpies of the 1,5-diyne and 1,2-diene-5-yne rearrangements by over 5.0 kcal/mol, as result of the stabilization effect of a formyl substitution attached directly to the unsaturated moieties of the products. (c) 2009 Elsevier B.V. All rights reserved. |
| 公开日期 | 2013-10-07 |
| 源URL | [http://ir.isl.ac.cn/handle/363002/2102]  |
| 专题 | 青海盐湖研究所_青海盐湖研究所知识仓储 |
| 推荐引用方式 GB/T 7714 | Xia, Yuanzhi,Zhou, Fengying,Li, Yahong,et al. Effect of electron-withdrawing group on the [3,3]-sigmatropicrearrangements of 1,5-enynes, 1,5-diynes and 1,2-diene-5-ynes: Atheoretical study[J]. JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM,2009,904(1-3):69-73. |
| APA | Xia, Yuanzhi,Zhou, Fengying,Li, Yahong,&Lia, Wu.(2009).Effect of electron-withdrawing group on the [3,3]-sigmatropicrearrangements of 1,5-enynes, 1,5-diynes and 1,2-diene-5-ynes: Atheoretical study.JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM,904(1-3),69-73. |
| MLA | Xia, Yuanzhi,et al."Effect of electron-withdrawing group on the [3,3]-sigmatropicrearrangements of 1,5-enynes, 1,5-diynes and 1,2-diene-5-ynes: Atheoretical study".JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM 904.1-3(2009):69-73. |
入库方式： OAI收割
来源：青海盐湖研究所
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