2004 Fiscal Year Final Research Report Summary
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 |
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| Section | 一般 |
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| Research Field |
Chemical pharmacy
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| Research Institution | University of the Ryukyus |
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Principal Investigator |
ANDO Kaori University of the Ryukyus, Collage of Education, Professor, 教育学部, 教授 (70211018)
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| Project Period (FY) |
2003 – 2004
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| Keywords | S_N2 reaction on the sp^2 carbon / addition-elimination / transition state / density functional calculation / intramolecular reaction |
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| 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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Research Products
(8 results)
