2003 Fiscal Year Final Research Report Summary
Development of Effective Preparation of Natural α-Tocopherol via Stereoselective Cycloaddition Reaction
| Project/Area Number |
13555252
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 展開研究 |
|---|
| Research Field |
Synthetic chemistry
|
|---|
| Research Institution | YOKOHAMA NATIONAL UNIVERSITY |
|---|
Principal Investigator |
INOUE Seiichi YOKOHAMA NATIONAL UNIVERSITY, FACULTY OF ENVIRONMENT AND INFORMATION SCIENCES, PROFESSOR, 大学院・環境情報研究院, 教授 (90017939)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MURAYAMA Toshiyuki TAKASAGO KOURYOU CO.LTD., CHIEF RESEARCHER, ファイン&アロマケミカル研究所, 主管
HONDA Kiyoshi YOKOHAMA NATIONAL UNIVERSITY, FACULTY OF ENGINEERING, ASSOCIATE PROFESSOR, 大学院・工学研究院, 助教授 (60231578)
|
|---|
| Project Period (FY) |
2001 – 2003
|
| Keywords | SALICYLALDEHYDE / VYNYL SULFIDE / 1,4-OXATHIANE / ORTHOQUINONEMETHIDE / FUSED TRICYCLES / FUSED TETRACYCLES / BIOACTIVE CHROMANES |
|---|
| Research Abstract |
This Project was undertaken to develop an effective preparation of natural α-tocopherol via stereoselective cycloaddition reaction.
1.As a preliminary examination, synthesis of a primary alcohol containing vinyl sulfide structure was studied and this was successfully obtaind from isobutanal dithioacetal via carbene addition.
2.The reaction of the above mentioned alcohol with salicylaldehyde afforded a new tricyclic 1,4-oxathiane by acid catalyzed cyclization.
3.An sulfide compound for the construction of B/C rings and terpenoid side chain was prepared form phytone via witting reaction and thioacetalization.
4.The cyclization between the terpenoid sulfide and salicylaldehyde afforded a tricyclic compound in a moderate yield. A similar reaction between substituted cyclohexanol instead of acyclic one with salicylaldehyde provided the corresponding tetracyclic compound. The both reactions proceeded with full retention of stereochemistry.
5.Reductive ring opening reaction of the heterocycles thus obtained was successfully achieved by the action of a silyl compound, and bicyclic chromans were obtained in a single step. α-tocol was obtained from the tetracyclic compound containing hydroxyl group at the 2 position of the A ring. The conversion of α-tocol into various tocopherols including α-tocopherol has been known, the above synthesis means a formal total synthesis of tocopherols.
|
