| Project/Area Number |
16350019
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Organic chemistry
|
|---|
| Research Institution | Saitama University |
|---|
Principal Investigator |
NAKAYAMA Juzo Saitama University, Graduate school of Science and Engineering, Professor (90092022)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SUGIHARA Yoshiaki Saitama University, Graduate school of Science and Engineering, Associate Professor (00272279)
ISHII Akihiko Saitama University, Graduate school of Science and Engineering, Professor (90193242)
|
|---|
| Project Period (FY) |
2004 – 2006
|
| Project Status |
Completed (Fiscal Year 2007)
|
| Budget Amount *help |
¥15,100,000 (Direct Cost: ¥15,100,000)
Fiscal Year 2006: ¥4,200,000 (Direct Cost: ¥4,200,000)
Fiscal Year 2005: ¥4,200,000 (Direct Cost: ¥4,200,000)
Fiscal Year 2004: ¥6,700,000 (Direct Cost: ¥6,700,000)
|
|---|
| Keywords | Diatomic sulfur / Triatomic sulfur / Sulfur monoxide / Disulfur monoxide / Addition reaction / Diels-Alder reaction / Singlet SO / Thiirene oxide / チオフェン1-オキシド / アルケン / アルキン / [1+2]環化付加反応 / チイラン1-オキシド / 一重項一酸化硫黄 / チイレン1-オキシド / チオフェン 1-オキシド / ジエン / [1+4]環化付加反応 / exo付加 / 二酸化二硫黄 / 二硫化酸素 / 逆ディールス-アルダー反応 / トリチオオゾン / 不均化反応 / 一塩化硫黄 / ディールス-アルダー反応 |
|---|
| Research Abstract |
The following reactive small molecules of sulfur were generated from the organic sources and their chemistry was investigated: 1) diatomic sulfur (S_2) that corresponds to a sulfur analogue of molecular oxygen O_2, 2) triatomic sulfur (S_3) that corresponds to a sulfur analogue of ozone O_3, 3) sulfur monoxide (SO) where one of the oxygen atoms of O2 is replaced by sulfur, and 4) disulfur monoxide (S_2O) where one of the oxygen atoms of sulfur dioxide (S_2O) is replaced by S.
The bicylic compound that carries an -S-SO- bridge underwent a retro-Diels-Alder reaction to extrude disulfur monoxide (S=S=O) in a reversible way at room temperature in solution. The resulting S=S=O undergoes a disproportionation through self-dimerization to give S_3 and SO_2 in the absence of suitable trapping agents. The S_3 acts as a 1, 3-dipole just like ozone and underwent 1, 3-dipolar cycloaddition toward strained alkenes, for example, norbornene. On the other hand, the S=S=O is trapped by dienes and other r
… More
eagents in good yields. Reactivities and DFT calucations of the molecule leads to a conclusion that S=S^+-0 is the major contributor of the ground state of this reactive species.
The Diels-Alder adduct that was formed by Diels-Alder reaction of a thiophene 1-oxide with dimethyl acetylenedicarboxylate underwent the SO extrusion at room temperature in solution with a driving force of the formation of a benzene derivative. The resulting SO was found to undergo hitherto unknown cycloadditions, i.e., [1+2] cycloadditions to alkenes and alkynes to give thiirane oxides and thiirene oxides, respectively. In particular, the later [1+2] cycloaddition to alkynes is synthetically important as a synthetic method of thiirene 1-oxide. It also undergoes [1+4] cycloadditions to acyclic dienes and cyclic dienes (polyenes) to provide a variety of cyclic sulfoxides; the addition to cyclic dienes is stereospecific. The reactivities of the SO leads to a conclusion that the SO produced by the present method is singlet and reacted with trapping agents without decay to more stable triplet state.
In addition, a few new reactions that generate diatomic sulfur(S_2) were developed. Less
|
