Organic Synthesis base on computational results : in-plane S_N2 reaction of haloalkenes
Project/Area Number |
15590014
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Chemical pharmacy
|
Research Institution | University of the Ryukyus |
Principal Investigator |
ANDO Kaori University of the Ryukyus, Collage of Education, Professor, 教育学部, 教授 (70211018)
|
Project Period (FY) |
2003 – 2004
|
Project Status |
Completed (Fiscal Year 2004)
|
Budget Amount *help |
¥2,500,000 (Direct Cost: ¥2,500,000)
Fiscal Year 2004: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 2003: ¥1,900,000 (Direct Cost: ¥1,900,000)
|
Keywords | S_N2 reaction on the sp^2 carbon / addition-elimination / transition state / density functional calculation / intramolecular reaction / SP^2炭素でのS_N2反応 / sp^2炭素でのS_N2反応 / 溶媒効果 / 活性化エネルギー / ハロアルケンへの分子内求核置換反応 |
Research Abstract |
The intramolecular nucleophilic cylization of haloalkenes was studied at the B3LYP/6-31+G(d) level in an Onsager continuum model for DMF(_=37.06). The reaction of (E)-2-(2-chloro-1-methylvinyl)phenol(E-1) takes a concerted in-plain σ-type S_N2 pathway with inversion at the sp^2 carbon with the activation free energy of 14.4 kcal/mol in DMF (17.1 kcal/mol in the gas phase). On the other hand, only π-addition transition structures were obtained from both Z-1 and the corresponding dichloroalkene with much higher activation free energies. These predictions were confirmed experimentally. We prepared haloalkenes 1. The E- and Z-isomers were separated by column chromatography and the geometries of the olef parts were determined by NOE experiments. When E-1 and Z-1 were treated with NaH in DMF, benzofuran was obtained in 95% yield from E-1, while Z-1 was recovered quantitatively even after heating at 110℃.
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Report
(3 results)
Research Products
(12 results)