| Project/Area Number |
17550037
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Organic chemistry
|
|---|
| Research Institution | Shimane University |
|---|
Principal Investigator |
YOSHIDA Masato Shimane University, School of Medicine, Professor (50137030)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MARI Iizuka Shimane University, School of Medicine, Research Associate (80222818)
|
|---|
| Project Period (FY) |
2005 – 2007
|
| Project Status |
Completed (Fiscal Year 2007)
|
| Budget Amount *help |
¥3,570,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥270,000)
Fiscal Year 2007: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2006: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2005: ¥1,400,000 (Direct Cost: ¥1,400,000)
|
|---|
| Keywords | Synthesis / Photoreaction / Fluorine Comnound / Photoestalyst |
|---|
| Research Abstract |
Organofluorine compounds possessing one or two fluorine atoms are expected to have unique biological properties, and the exploitation of the synthetic methods is still an important subject in organofluorine chemistry. The building-block strategy has now become one of the most convenient approaches for the synthesis of organofluorine compounds, and considerable efforts have been devoted to the development of the synthetic methods. Ring-opening reactions of difluorocyclopropane derivatives with nucleophiles have been already reported, and applied to the syntheses of various organofluorine compounds such as 24.24-difluoro-25-hydroxyvitamin D_3. In this study, we have developed the novel synthetic route for fluorinated heterocycles.
We started our research from the exploration of ring-opening reaction of difluorocyclopropanes using new redox systems on titanium oxide. The difluorocyclopropanes were synthesized by the modified method described in a literature from α-methylstyrene with sodium
… More
trifluoroacetate. The cyclopropanes were photoirradiated in the presence of titanium oxide as a photocatalyst under various conditions. However, the ring opening by the photocatalitic reaction did not occur.
Therefore, we extended our research interests to the development of the convenient method for the synthesis of fluorinated heterocycles using molecular transformation of small rings as the key reaction. We found the production of ketones by the reaction of radical cations of olefins with radical anion of oxygen via four-membered rings, dioxetanes. As a general procedure, fluorinated α-methylstyrene with titanium oxide was photoirradiated under oxygen, and the products were treated with hydrazine acetate. Fluoroalkylated pyrazole was obtained in sufficient yield. The mechanism was studied electrochemically using cyclic voltammetry. The starting fluoroalkylated olefin was readily synthesized from α-methylstyrene with perfluoroalkyl iodide by photocatalitic reaction as was developed by us. Thus, the method developed here is expected provide a useful synthetic way for fluorinated heterocycles. Less
|
